IAEA-TECDOC-243
NUCLEAR TECHNIQUES FOR STUDYING CHEMICAL RESIDUE PROBLEMS IN EDIBLE OIL SEEDS AND RELATED PRODUCTS
REPORT OF A RESEARCH CO-ORDINATION MEETING ORGANIZEE TH Y DB JOINT FAO/IAEA DIVISION OF ISOTOP RADIATIOD EAN N APPLICATION ATOMIF SO C ENERGY FOR FOOD AND AGRICULTURAL DEVELOPMENT AND HELD IN VIENNA, 9-13 JUNE 1980
A TECHNICAL DOCUMENT ISSUEE TH Y DB INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1981 NUCLEAR TECHNIQUE STUDYINR SFO G CHEMICAL RESIDUE PROBLEMS IN EDIBLE OIL SEEDS AND RELATED PRODUCTS IAEA, VIENNA, 1981
Reproduced by the IAEA in Austria February 1981 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK The IAEA does not maintain stocks of reports in this series. However, microfiche copie f thesso e report obtainee b n sca d from INIS Microfiche Clearinghouse International Atomic Energy Agency Wagramerstrasse 5 P.O. Box 100 A-1400 Vienna, Austria prepaymenn o $1.0S U f againsr 0to o IAEe on t A microfiche service coupon. FOREWORD
Bie increasin chemicalf o e g us protectinr sfo g crops, livestocd kan human health against pesdiseasd tan e attac dictates ki neede th sy db of a rapidly growing world population. Notwithstanding these trends there is also a growing public sensitivity to contamination of the agricultural environment. Chemical residues inevitably find their way into human food and the environment. Since 1969> the Joint PAO/IAEA Division of Isotope and Radiation Applications of Atomic Energ Poor Agriculturad yfo dan l Developmen coordinates tha widda e range of isotopic tracer-aided studies of trace contaminant problems.
Unde currene rth t programme» whic initiates hwa 1975n di Internationae th » l Atomic Energy Agenc publishes yha d "Radiotracer studie pesticidf so e residues in edible oil seeds and related products" (1979) in i*s technical document series presene Th . t report represent appraisan sa l of a group of studies, with particular emphasis given to the many problems of developing countries. Nuclear techniques have provided powerful research stude tool th thes f yo n s i e problems. generosite Thankth e o st th f yo Swedish International Development Authority (SIDA) bees ha n t ,madi e possibl undertako et numbeea thesf ro e studie developinn si g countries. CONTENTS
. 1 COMMUNICATIONS Residue f so C-cyolan cottonseen ei d products ...... 7 . S.M.A.D. Zayed, I.M.I. Fakhr, M.E. Bahid gan A.Z. Osman Cyolane residues in milk of lactating goats ...... 13 S.M.A.D. Zayed, I.M.I. Osma. FakhA d nran Pate of leptophos residues in milk products ...... 19 S.M.A.D. Zaye S.Id dan . Mohammed Pate of dimethoate in olives and in olive oil ...... 23 Nasri S. Kawar Residue cottonseen si cakd an el resultindoi g froe th m combined applicatio dimethoatd an T DD f eno ...... 9 2 . G.A. ElZorgan M.Md ian . Ahmed Monocrotophos residues in cottonseed and related products ...... 7 3 . Jami. M l Qureshi Satta. ,A M.Hd ran . Naqvi Carbaryl residue maizn si processed ean d products ...9 .3 Jami. M l Qureshi Satta. ,A r (Jr. M.Hd )an , Naqvi Carbaryl residues in cottonseed products in the Philippines ...... 45 Pelip Pabl. aE o residueT DD groundnun si changed tan residuen si s during processing of groundnut oil ...... *° K. Raghu, N.B.K. Murthy and J. Perreira Pate of technical and C —labelled BHC residues in rice grain ...... 55 d Yong-HwSu—Raan e Le e a Kirn Neoasozine residue ricn i s e ...... 3 6 . Su—Rae Lee and Yong—Hwa Kim
2. REPORT ...... 69 2.1 Introduction ...... •>•..••• 69
2.2 Meeting objectives ...... 70 2.3 Some highlights ...... 0 7 . 3. RECOMMENDATIONS ...... 1 7 . 4. CONCLUSIONS ...... 2 ^ .
5. LIST OF P&RTICIPANTS ...... 75 1. COMMUNICATIONS
OP 14C-CYOLANE IN COTTONSEED PRODUCTS
S.M.A.D. ZAYED, I.M.I. FAKHR+, M.E. BAKEG4"1" and A.Z. OSMAN M.E. Regional Radioisotope Centre, Dokki, Cairo Arab Republic of Egypt
ABSTRACT
The systemic insecticide cyolane £2-(0,0-diethylphosphoryl)-imino- 1,3-dithiolane prepares Jwa d from C-ethanol, phosphorus oxychloride and 2-amino-l,3-dithiolane. Cotton plants were treated wito htw application insecticide th f so e under condition locaf so l agricultural practice. 1 4harvestee C-residue th cakd f crudan e eo l th deoi n s i cotto n seeds amounte 1.6o dt 0.01d 3an 4 rog/kg respectivelye th . f o Abou $ 50 t C-activity present in the crude oil was found to be eliminated by simulated commercial processes userefininr oildfo e th .f go Alkal i treatment and bleaching removed 16% and 2f>% of the radioactive residues respectively day3 . r sWinterizatiofo C 7 5- bleachee t th a f l no doi effecte furtheda r eliminatio 13$f no . C-residue cottoe th n nsi seed products and in the samples of the refined oil were characterized and the main constituents identified using chromatographic techniques.
INTRODUCTION
Cyolane, 2-(0,0-diethyl-phosphoryl)imino-l,3-dithiolane (l) is characterize systemis it y db c activit comparativeld yan y long residual action provet highlI e .b o dt y effective agains differene tth t instars cottoe ofth n leaf worm Spodopter recommendes wa ad littoralian ) (2 d ) s(l for controllin numbega economicallf ro y important cotton pests (3-7). It became, therefore, important to study the possible deposition of cyolane residues in the cotton seed, oil and cake of treated cotton plants. For this purpose, C-cyolane was synthesized in our laboratory. The effects of simulated commercial processing procedures on C-cyolane residues were studied.
.V0" //S—CH_/-k2
-CH2
+ National Research Centre, Itokki, Cairo, Egypt "*"*" Kept, of Radioisotopes, Atomic Energy Establishment, Cairo, Egypt MATERIALS AM) METHODS
14.C-Cyolane
) a Bthylene dithioovanate; This compoun prepares dwa heatiny db molg1 e ethylene dibromide wit mole3 h 2. potassiu f so m thiocyanat absolutn ei e ethanohours0 1 r .lfo After crystallization from ethano produce lth t melted at 88°(lit.m.p. 90°) ((8) (9).
b) Cyclic ethylene dithioimido carbonate (ll); Bfchylene dithiocyanate was cyclized by heating with concentrated hydrochloric acid at 100° for 10 hours to yield the hydrochloride of II. 5br purification of the hydrochloride reactioe ,th n mixtur cooleds ewa , neutralized with potassium carbonat extracted ean d with benzene driee Th .d benzene layes rwa saturated with HC1 gas where the hydrochloride of II separated out (m.p. 208°; lit.m.p. 202°) (10). II was stored in the form of its hydrochloride since the free base decomposes more readily. The free base was liberated by neutralization of the hydrochloride with 10$ potassium carbonate solution and subsequent extraction with benzene.
c) Bthyl-l-14C-labelled cyolane (l); Bthanol-l-14C (40 mmol, ImCi) was allowed to react with phosphorus oxychloride (20 mmol) in presence of pyridin givo et e diethyl phosphorochloridate (ill). C-cyolans ewa synthesized by the interaction of III with the equivalent amount of II. The crude produc s purifietwa silica n columl do age n till radiopurity, as determine thiy db n layer chromatography. C.cyolane melte t 39»da ; 5 specifi; yielmg 0 d66 c activity 1.643 mCi/gf R--value thin so n layers of silica gel 0.76 in benzene: ethyl acetate (3:2) and 0.88 in benzenes ethanol:acetic acid (79:14:7).
0 + X'H-P-I l NC XS—CH,
HI II
Cultivatio analysisd nan ;
Cottonseeds were sow alluvian ni l soil under normal field conditions on Februar 1979, y25 * Irrigation, fertilizatio soid nan l management were carried out as practiced in the field. Plants were treated with radioactive cyolane twice wit two-weeha k interval during June 1979» The insecticide was applied as acetone/water suspension to the leaves of isolated five plants at the rate of 20 mg C-oyolane per plant per application harvestt A . , seeds were collecte extracted dan d with ether in a soxhlet apparatus for 6 hours,then with methanol for further 6 hours. Extracts were concentrated under reduced pressur analyzed ean r dfo radioactivity.
For characterization purposes, C-residues were extracted from partitioniny b l thoi e g between acetonitril n-hexaned ean . Cyolane and cyolane-derived residues remained in the acetonitrile layer, which analyzes wa papey db r chromatograph solveno tw n yi t systems -using authentic substances as references (Table II). Spots were made visible by spraying with Hanes Isherwood reagent (ll).
Commercial processing procedures;
Crude cottonsee fortifies wa l doi d with cold dC-cyolanan n a o et end concentration of 7
Alkali refining; - 20 ml samples of the fortified oil were shaken with 2N sodium hydroxid minutes0 3 r eamoune fo solutioTh .° f to 50 t na alkal excesn i i$ thaf so adde10 ts calculatedwa e basie th th f so n d o acid value mixture Th .centrifuges ewa werl aliquotd oi e dan e th f so countod.
Bleaching alkale Th ;- i treaterefines wa l ddoi with 0.5$ activated carbon and a factory-grade bleaching earth (l;l). The mixture was stirred vigorously at 80-100 for 20 minutes. The bleached oil was then separated and counted.
Winterization winterizes wa l r cleaoi fo e about y Th da 7 r dr ;- t5- day3 s followe centrifugationy db countingd ,an .
Samples of oil, after individual treatments were partitioned between acetonitrile and hexane for characterization of ^C-residues.
Radiometric measurements;
cak d Radioactivitdetermines an e wa l oi e combustioy dth b n yi a n ni Packard-Oxidizer syste d C-activitman 1determine4s ywa Packara n di d Tri-Carb Liquid Scintillation Spectrometer. Paper chromatograms were scanned by a radioscanner. RESULT DISCUSSIOND SAN S
The appearanc variablf eo e amount insecticidf so e residue seen si d oils has been reported by several authors (12-17). The present in- vestigation reveale presence dth f eo C-cyolan e residue cottoe th n nsi seed products. Gyolane residue cottonseed,oile th n si cakd ,an e were 0.34foune b o dt , 1.6 0.01d 3an 5 mg/kg respectively (Tabl . ResidueeI) s in oil were found to consist of lipophilic (31$) and hydrophilic compounds (6$$) (Table II). Metabolites found in the oil were also detected in the cake which containe least da more ton e unknown metabolite (Table II). Radio-paper chromatographic studies reveale presence dth cyolanef eo , mono diethyd -an l phosphates (Tabl wit) eII h relative abundancf eo 2:3:2 in the crude oil.
Gyolane-fortified crude oil was subjected to the refining processes in a stepwise manner simulating actual commercial processing procedures. The individuae effecth f to l processe levee - naturth d C lan n s o f eo activity is illustrated in Table III. The data indicate that the processing procedures effected originae removath f o abouf lo ^ t50 C-activity. Analysis of C-residues in the refined oil samples indicated the presence of cyolane degradation products which were identifie monoethyls da diethyd -an l phosphates together wit smalha l amount of an unknown metabolite (Table III). The process of alkali refining effected a conaiderable decomposition of the toxicant. Other processes had no appreciable effect on cyolane. In general, the results obtained indicate that cyolane is fairly persistent towards processing procedures of the oil when compared with other insecticides such as lindane and carbaryl (18).
The daily intake of cyolane residues from cotton seed oil may be estimate average th r edfo individua consumeo lwh g averagn 0 sa 50 f eo monthoir lpe . This amount which correspond cyolan g abouo st ji 7 t2 e per day, is an index of the insecticide burden in Egyptian subjects from this source. Residues from other important sources suc milks ha , meat, etc. however, remain unknown.
TABLE I; 4C-cyolane residues in cotton seed products
Sample tft. 14G -activity Residue of sample (cpm) (mg/kg)
C -cyolane 1.0 pg 3450 Oil 9.2 gra 51750 1.63 Cake 36.0 gm 1849 0.015 Total seed 45.m g 2 53599 0.34
10 TABLE II; Nature of C-cyolane residues in cottonseed oil and cake
* **• Material Naturf eo Compound R "sreantage residue f A B
Oil hydrophilic monoethyl phosphate 0.12 0.15 42 di ethyl phosphate 0.47 0.76 27 lipohilic cyolane 0.90 0.95 31
Cake hydrophilic monoethyl phosphate 0.12 0.15 26 diethyl phosphate 0.47 0.76 30 xudanoHin 0.76 0.80 10 lipophilic cyolane 0.90 0.95 34
* A = Benzene, methanol, acetic acid (79:14:7) B = Isopropanol, water, ammonia (75:24:1)
** Total 14C-residues = 10OJ&
TABLE III; Effect of simulated commercial processing procedures on C-cyolan cottonseen ei l doi
Procedure Concentration Percent radioactivits ya of retained C-residues Monoethyl Diethyl Unknown Cyolane (mg/kg) phosphate phosphate
Crude oil 7.0 100 Alkali refining 5.9 7 65 0 28 Bleaching 4-4 13 59 17 11 Winterization 3.6 13 66 5 16
11 REFERENCES
] C.S[I . SERGHIOU Econ. ,J . Entomol. (19715 11 , ),64 [2] R.L. RIDGWAY, L.J. GORZYCKI and D.A. LINDQUIST, J. Econ. Entomol., 6 (19655_866 , ) ] D.L[3 . BULL, D.A. LINDQUIS V.Sd Tan . HAUSE Econ. ,J . Entomol., 5J., 112 (1964) [4] R.L. RIDGWAY, S.L. JONES and L.J. GORZYGKI, J. Econ. Entomol., 5j?, 149 (1966) [5] R.L. RIDGWAY, H.J. WALKER, R.L. KAMA and W.L. OWEN, J. Boon. Entomol. 60, 592 (196?) [6] J.W. DAVIS, W.G. WATKINS Jr., C.B. COWAN Jr., R.L. RIDGWAY and D.A. LINDQUIST, J. Econ. Entomol., 5_£, 159 (1966) ] J.W[7 . DAVIS, C.B. COWAN Jr., W.G. WATKINS jr., P.O. LINDGREd Nan R.L. RIDGWAY Econ. ,J . Entomol., 5_£, 980, (1966) ] H.L[8 . BUFF, Ann. Chem., 100 (18659 ,29 ) [9] L. GLUTZ, Ann. Chem., 153, 313 (1870) MIOLATI. A [10] , Ann. Chem., 212 (18925 ,6 ) [II] C.S. HANES and F.A. ISHERWOOD, Nature, 164, 1107 (1949) [12] S.M.A.D. ZAYBD, S.A. MANSOUR, I.Y. MOSTAFA and A. HASSAN, Trace contaminant agriculturef so , fisherie food developinsn an i d g countries, IAEA, Vienna (1976), STI/PUB/454, p. 89 [13] S.M.A.D. ZAYED, S.A. MANSOUR, I.Y. MOSTAFA and A. HASSAN, Radiotracer studies of pesticide residues in edible oil seeds and related products, IAEA-218, Technical Document Series, Vienna (1978), p. 13 [14] M.J. QURESHI, Radiotracer studies of pesticide residues in edible oil seeds and related products, IAEA-218, Technical Document Series, Vienna (1978), p. 21 HASSAN. A [15] , S.M.A.D. ZAYED, I.Y. MOSTAFA, Trace contaminantf so agriculture, fisheries and food in developing countries, IAEA, Vienna (1976), STI/PUB/454, p. 59 [16] A. HASSAN, S.M.A.D. ZAYKD, and I.Y. MOSTAFA, Radiotracer studies of pesticide residue edibln si seedl related eoi san d products, IAEA-218, Technical Document Series, Vienna (1978), p. 63 [17] M.J. QURESHI, Radiotracer studie pesticidf so e residuen si edible oil seeds and related products, IAEA-218, Technical Document Series, Vienna (1978)9 5 . ,p [18] K. RAGHU, M.G. MENDES, N.B.K. MURTHY and J. PERREIRA, Radiotracer studie pesticidf so e residue edibln si seedl relateed oi san d products, IAEA-218, Technical Document Series, Vienna (1978). 3 . ,p
12 CYOLANE RESIDUES IN MILK OP LACTATING GOATS
S.M.A.D. ZAYED, I.M.I. OSMAPAKHR. A d N an + Middle Eastern Regional Radioisotope Centre Dokki, Cairo, Egypt
ABSTRACT
Consecutive feedin lactatinf go g goats with C-alkyl labelled cyolan day5 dietart r s a m efo resulteop ye 6 1 th level d n di an s8 appearance of measurable insecticide residues in milk (0.02-0.04 mg/kg). The residue levels were markedly reduced afte withdrawara l periof do days7 . Analysi urinf so mild ean k residues showe presence dth f eo similar metabolites in addition to "the parent compound. The major part of the residue consisted of mono-, diethyl phosphate and 2 hydro- philic unknown metabolites.
The erythrocyte cholinesterase activity was reduced to about 50$ after 24 hours whereas the plasma enzyme was only slightly affected animale Th . s remained symptom-free durin experimentae gth l period.
INTRODUCTION
Cyolane [2-(0,0-diethyl phosphoryl)-imino-l,3-dithiolane]n a s ,i organophosphorus insecticide, usecontror fo d cottof lo n pest Egyptn si . The presence of C-^alkyl labelled cyolane in cotton seed products was previously reported (l). Cyolane residues in the seed, crude oil and cake were 0.34» i.S3 and 0.015 mg/kg respectively. In an attempt to evaluate the impact on human health, residues from other sources, such as mil mead dairkf an to y animals grazin contaminaten go d silagr o e feedin cottoe th n ngo seed cake take e havb o net into consideration.
The aim of this investigation was to study the extent of deposition of cyolane and/or its metabolites in milk and organs of lactating goats. The nature of the radioactive residues in milk alss wa o characterized.
National Research Centre, Dokki, Cairo, Egypt
13 MATERIAL MBTHOBD SAN S
14C-oyolane;
Pure 14C-alkyl labelled insecticide was prepared from ethanol- 1- C, phosphorus oxychloride and 2-amino-l,3-dithiolan according to Zayed et al (l); specific activity 1.643 mCi/g, lj»g = 3450 cpm in the counting system.
Animal dosing and sampling;
Five healthy lactating goats (average weight 22 kg) were aclimatized during 15-day pretest period which permitted adjustments to feeding and environment. Bach anima gram0 dails 2 llocaf wa d so y fe l bread followe regulay db r feed which consisted mainl cloverf yo , brad nan straw addition I . controa o nt l goaanimale tth s were grouped into otw groups as follows: -
Group Numbef ro Administered dose Dietary level goats
I 2 20 mg/day/goat 8 ppm II 2 40 mg/day/goat 16 ppm
The dietary level is based on a mean of two and half kilograms feed per goat per day. Pilot experiments in which silage was treated with cyolane showed that, under regular feeding procedures, a goat would consume 0.4 - 0.8 rag cyolane/kg body weight. A solution of the appropriate dos acetonn ei s appliee wa piec a o breadf dt eo . After evaporation goatsolvente e th th s o f morning e t o earl th d , n breafe yi s .dwa The toxicant was administered to both groups of goats for 5 consecutive days and then given regular feed for 7 days.
Milk samples were collecte consecutiv2 1 r dfo e days. Goats were milked twice sample l dailp.mm 6 a.m9 d 0 t .ya an 10 s were use analysisr determinatioe dfo th r Fo . erythrocytf no plasmd ean a cholinesterase activity (2), blood samples were collected from the juglar vein 24 hours after treatment and at the end of the withdrawal period. Urine samples were collecte characterizatior dfo metabolitesf no .
Animals were sacrificed after the recovery period. Brain, heart, liver, kidney, whole blood, lean muscle and fat were analyzed for 14C-activity.
14 ANALYSIS
Milk, urin orgad ean n samples were combuste Packard-Oxidizea n di r syste d C-activitman determines ywa Packara n di d Tri-Carb Liquid Scintillation Spectrometer. Residue miln si k were separated according tstandaroa radiochromatographid d an procedur ) (4 ) e(3 c techniques were used for characterization and identification of milk and urinary metabolites.
RESULTS
There were no adverse reactions (due to feeding of cyolane) with regar milo dt k production, food consumptio behaviorar no l reactions. Pig show.1 s that milk collected from goatcontaineI I groupf d so an sI d small but measurable amounts of radioactivity. Analysis of residues in milk showed that the parent compound represented only 9$ of the total residues (Table l). Milk obtained at 6 p.m. usually contained more residues than that collected in the morning. At 16 ppm, the residue level in milk ranged from 0.04 to 0.06 mg/kg during the test days. During withdrawal these were reduced to about 0.01 mg/kg.
Residue differenn si t organs afte withdrawara l perio day7 e f sar do show Tabln ni . ConcentrationeII omentaliven d si an rt lwerfa e found to be 0.11 mg/kg.
The urin firs e goatf fifted th o tan n so h test days contained 2.0 to 2.4 mg/kg of C-residues which decreased to 0.04 to 0.06 mg/kg at the end of the withdrawal period (Table III). Urinary C-metabolites were similar to those found in milk. Measurement cholinesterasf so e activit hour4 y2 s after administration of cyolane showed that the erythrocyte enzyme was significantly inhibited while the plasma enzyme was only slightly inhibited. The erythrocyte enzyme, however, recovered at the end of the withdrawal period.
DISCUSSION
Consecutiv cyolanf o em feedino pp et day5 6 1 r sd gfo wit an h8 lactating goats resulte measurabla n di e amoun residuef to milkn si . Cyolane residue miln si k were lower than thos othef eo r organophosphates suc leptophos ha s (0.40 mg/kg) (5) parene «Th t compound constituted only one tenth of the total residues while leptophos contributed more than 50$ of the total residues in the milk (5)« The low cyolane levels iattributene b mil y kma fastea o dt r biodegradatio insecticide th f no e in goats. Previous studie ratn si s treated with C-insecticid14 e labelle iminodithiolane th n di e ring indicated e thath tf o abou $ t50 radioactivity was excreted in the urine and feces after 24 hours (6).
15 Inhibitio plasmf no erythrocytd aan e cholinesteras linn i es ei wit h the data reporte ratr fo ds (7).
In conclusion, cyolane is apparently metabolized rapidly in goats and doeaccumulatt no s tissuesn residuew ei lo e Th .s foun miln di e kar not likel preseno yt healtta h consumerhazare th o dt .
REFERENCES
[1] S.M.A.D. ZAYED, I.M.I. PAKHR, M.K. BAHEG and A.Z. OSMAN, This issue. H.O] [2 . MICHEL Lab. ,J . Clin. Med., 34., 1564 (1949) ] H.W[3 . DOROUGH, International Unio Purf Appliedd no ean . Chemistry, "Pesticide Terminal Residues*, Tel-Aviv, Israel, 1971, p. 173 [4] J. MIYAMOTO, M.L. KEPLINGER, R.J. WINGENDER, Y. TAKEMOTO and D.H. JENKINS, J. Pesticide Sci., 2, 1 (1977) HASSAN. A ] PARGHAL. ,M [5 S.Id Yan . MOHAMED, Radiotracer Studief so Pesticide Residues in Edible Oil Seeds and Related Products, IAEA-218, Technical Document Series, Vienna (1979)3 7 . ,p ] I.P[6 . KAPOOR R.Cd ,an . BLINN Agr. ,J . Pood (19773 Chem.41 , ),2£ ] M.R.B[7 . BAHIG, Experientia, 31. (19756 ,83 )
0.03
group II 0.01
345 6789 10 11 12 Fig.1 lAC-Cyolane residue n mili s k ->• days
16 TABLE I; C-cyolane residues in milk of lactating goats
Compound R,.-value Percentage (Total 14C- activity = 100%) A B
Monoethyl phosphate 0.12 0.15 7
UnknownI 0.30 0.34 17
Diethyl phosphate 0.47 0.76 55
UnknowI nI 0.?6 0.85 12
Gyolane 0.90 0.95 9
Paper chromatography ins
A) Benzene, methanol, acetic acid (79:14s7) B) Isopropanol, water, ammonia (75s24:l)
TABL ; II E C-residue n organi s f goato s s after 7 days withdrawal period
Organ C-residue (mg/kg) Group I Group II
Brain 0.066 0.072 Liver 0.082 0.106 Heart 0.070 0.084 Kidney 0.060 0.080 Longissimus Dorsi 0.062 0.066 Biceps Femoris 0.072 0.076 Blood 0.033 0.046 Oraentat lfa 0.086 0.106 Subcutaneous fat 0.070 0.074
Dat e basear a weighn do f organo t s
17 TABLE III: C-residues in urine
Dayn so Days after end C-residue (rag/kg) treatment of treatment Group I GrouI pI
1 —— 2.04 2.38
5 —— 2.12 2.41
- 7 0.04 0.06
TABL ; PlasmEIV erythrocytd aan e cholinesterase activity after 24 hours treatment
Dietary level Plasma Erythrocyte (ppm) APH % remaining ApH % remaining activity activity
Control 0.54 100 0.34 100
8 0.49 91 0.20 59
16 0.48 89 0.16 48
18 PAT LEPTOPHOP EO S RESIDUE MILN SI K PRODUCTS
S.H.A.D. ZAYE S.Id Dan . MOHAMMED M.E. Regional Radioisotope Centre Dokki, Cairo, Egypt
ABSTRACT
The fat leptophof eo s residue varioun si s milk products swa studied using C-phenyl labelled leptophos. Milk products were prepared from milk fortified with the radioactive insecticide "by methods simulating those used in industry. The highest leptophos level was foun lowes e butten dth i skin d ti ran m mil wheyd kan . Analysif so the radioactive residues in all products showed the presence of leptophos alone oxoe tracA .th n f couleo detectee db wheyn di e Th . results obtaine thin di s investigation indicated that processinf go affect no naturmil e d tth k di leptophof eo appreciably an o st e extent.
INTRODUCTION
The insecticide 0-(4-bromo-2,5-dichlorophenyl) 0-methyl phenyl- phosphonothioate (leptophos) is effective against several pests attacking field crops and has been, until recently, used for controlling the cotton leaf worm in Egypt. Recent investigations (l, 2) showed the appearanc leptophof eo s residue cotton si n caked seedse an Th .l ,oi deposition of leptophos residues in the milk of dairy animals could also be demonstrated by experiments with C-phenyl labelled insecticides (3). It seemed, therefore, necessary to study the fate of leptophos residues in processed milk products suc butters ha , cream, chees yoghurtd ean .
MATERIALS AND METHODS
C-phenyl labelled leptophos; The radioactive insecticide was prepared according to the method described by Zayed et al (4) using benzene . LeptophoC - 1 -1 4c sf C . Leptophos formed colourless crystals from n-hexane, m.p. 7o2 , spec. act. 1 mCi/g.
Preparation of milk products; 800 ml buffalo milk were used for the preparatio eacradioactivf e no th h f producto g m e0 2 .insecticid e freswerf o eg h k addemil1 o kdt directly before processing brieA . f accounpreparatioe th n differento e th f no t milk product gives si n below:
19 •"•• Yoghurt; Starter was added to pasteurized milk which was incubated hours9 startee r Th fo . 5 ar3 t containe35 ford 9 hours. The starter contained Streptococcus thermophilus, Thermobacterium bulgaricum and Th. yoghurt.
2. Cream and butter; Milk was shaken in a separatory funnel at 35 for about 10 minutes and cream was mechanically separated. For preparatio butterf no , crea s firsmwa t separateintermitteny b 2 t da t shaking for few minutes. Further shaking at room temperature led to separatio butterf no .
3. Cheese;
(a) Full, cream cheese; The fortified whole milk was salted and mixed with the rennet extract at 37 • The mixture was allowed to stan that a d t temperatur threr fo e e hours. After complete coagulation the curd was allowed to drain. i (b) Cottage cheese; Skim milk obtained after separation of cream heates minute0 wa 3 60—6 o 5 adt r 3 thed t fo san 5n cooled to 22 . Ufa of the starter (containing Streptococcus lactis) s addewa d followe additioy d b renne e th f tno extract. After complete coagulation witt cu knifha cure s warmed ,th dwa ean d 0 twito4 h agitatio alloo nt w optimum separatio wheye th .f no
Radiometric measurements; Radioactivity level in butter, cream, cheeses and yoghurt was determined by combustion in a Packard -Oxidizer system and G-activit s determineywa Packara n di d Tri-Carb liquid scintillation spectrometer. Skim milk was directly counted for its radioactivity. Yoghurt was analysed after being blended to ensure uniformity of the sample. Thin layer plates were scanne radioactivitr dfo y usin manuallga y operated device (GM tube) connected to a sealer.
Isolatio characterizatiod nan radioactivf no e residues; Residues in cream and butter were isolated by extracting a 2g sample with hexane;ether 1:1 (20 ml). The extraction was repeated twice and extracts were filtered and reextracted 3 times with acetonitrile each)l m 5 .(1 Extracts were then concentrated under reduced pressure.
Cheese (25 g) was homogenized with water (25 ml) and homogenate blended wit hminute5 acetonitrilr fo s) followeml 5 e(2 additioy db n of 5 ml of acetone. After separation of solids formed, the residue was extracted with acetonitrile/acetone (25/5 combinee ml)Th . d acetonitrile-acetone extracts were washed twice with hexane (10 ml each) to remove fat.
20 Yoghurt (30 g) was blended with 45 ml acetonitile for 5 minutes followed by addition of 15 ml acetone and shaking was continued for one minute. After filtratio residue nth washes ewa d witl m mixturha 5 4 f eo acetonitrile and 15 ml acetone. The combined extracts were washed twice with hexane (10 ml each) and then concentrated.
Skim milk (30 ml) was extracted twice with 45 ml of acetonitrile/ acetone (2:1) extracte Th . s were concentrated under reduced pressure. Ghromatographic techniques used for identification of leptophos residues included two solvent systems (Ethylacetate/hexane, 1:9 and Petroleum ether/benzene, 5sl)«
RESULT DISCUSSIOD SAM N
Leptophos residue processen si d milk product showe sar Tabln ni . eI Cheeses retai considerablna e originae amounth f o t l radioactivity (46^ and 885^ in cottage and full cream cheese, respectively). Butter containe highese dth t leve radioactivitf lo whed lowese yan y th t level. Analysi radioactive th f so e residue mill al kn si product thiy sb n layer chromatography showe presence dth leptophof eo s only tracA . f eo leptophos oxon (less than 0.1$) could be identified in skim milk. Identificatio mads nchromatographwa y eb Buianol:ethanol:watern yi : ammonia (20:40:39;! Butanol:pyridine:wate0.92n . i ) (R d )an r (6:4:3)
(Rf 0.79 (5).
The high concentratio leptophof no butten i s r probably relates it o st strong lipophilic nature. Skim milk contained only a small amount of leptophos relativele Th . y high residue observe cottagn di e cheesy ema be explained on the basis of possible insecticide binding to proteins and in part due to incomplete skimming under the experimental conditions.
Leptophos, which constitute majoe sth r residue deposite miln di k (3) would not suffer change by processing into milk products and would concentrat butten ei cheesed ran insecticide Th . e level decreases ordee inth r butter ^full cream cheese^ cream ^cottage cheese^ skim milk^ whey.
RBFEIRBTCBS i
HASSAN. A ] ,[l S.M.A.D. ZAYE I.Yd Dan . MOSTAFA, Trace contaminants of agriculture, fisherie food developinn an sdi g countries, IAEA, Vienna (1976), STI/PUB/4549 5 . ,p HASSAN. A ] ,[2 S.M.A.D. ZAYE I.Yd Dan . MOSTAFA, Radiotracer studies pesticidf o e residue edibln si seedl eoi related san d products, IAEA-218 (1979), Technical Document Series, p. 63
21 [3] A. HASSAN, M. PARGHALY and S.I. MOHAMED, Radiotracer studies of pesticide residue edibln si seedl relateed oi san d products, IAEA-218 (1979), Technical Document Series, p. 73 l S.M.A.D[4 . ZAYED, I.M.I. HASSAN. A PAKH d Ran , Environmental Quality and Safety; Suppl. Vol. Ill, p. 713 (1974) [5] S.M.A.D. ZAYED, M. PARGHALY and A. HASSAN, Isotopenpraxis, 14 68 (1978)
TABL ; EI C-residue processen si d milk products
14 Sample C-residue Percentage * (mg/kg)
Milk 20.0 Yoghurt 21.0 99 Butter 136.0 18 Cream 44.0 29 Pull cream cheese 68.0 88 Cottage cheese 39.0 46 Skim milk (from cottage cheese) 7.0 8 Whe fulf yo l cream cheese 1.2 3
* Datmeae replicatf aar no e experiments
22 FATE OF DIMETHOATE IN OLIVES AND IN OLIVE OIL
Nasri S. KAWAR Faculty of Agpi cultural and Food Sciences American University of Beirut, Lebanon
ABSTRACT
Dimethoat applies ei baia s tcontroe da sr>rath r f lo yfo Dacus oleae fate dimethoatf Th .eo olivoliven n ei i l d eoi s an was studied. It was found that the residues of the insecticide decreased rapidly in the olives, and the rate of dissipation was influence weathey db r conditions oxygee Th . n analog, dimethoxon, onle th y s metabolitwa e detected. Processin olivee th r f gso o extraction of the oil also resulted in a sharp reduction of dimethoate residues in the final products.
INTRODUCTION
Olive plantations in Lebanon constitute the largest area devoted crope ton o . About 28,000 hectare plantee sar d with olive treesf ,o which 23,000 hectares have bearin e treeth n si g stag producd ean e about 50,000 tons of olives annually. The crop is utilized in several ways: the olives are pickled and consumed, or the oil is extracted from the fruits and eaten either raw or cooked with a wide variety of foods. Inferior grades of oil are utilized in the production of soaps, while the olive-seed meal is used in animal feed.
The olive fruit fly, Dacus oleaemajoe th rs , i insec t pes olivef o t s and causes extensiv econtroo cron lossee f th pi o lst measure appliede sar . Several insecticides wer pase dimethoatet useth tbu n di , appliea s da bait spraymose th t s ,commonli y used chemica presentt la .
A numbe studief ro s were conducte Mediterranean di n countries especially Greece and Italy, on the fate of dimethoate in olives. These are reviewed by De Pietri-Tonelli et al. (l). Steller and Pasarell publishe) a(2 resulte dth comprehensiva f so e e studth n yo fate of dimethoate and dimethoxon in plant and animal tissues, milk and eggs. However, this problem has not been investigated in Lebanon, and thus the present study was undertaken.
23 MATERIAL METHODD SAN S
Field Experiment
The major olive production region Northere th Lebanof n so i ne nar and Souther ncountrye partth currenf e o sTh . t experimen s conductetwa d irelativela n y small grove clos Beiruto et . Unfortunately ownee ,th r did not approve of the use of labelled material on his trees. Thus, choico fiele n th t carrd wdebu ha t woryou k using unlabelled dimethoate. The common practice use Lebanon i d controo nt olive lth es i frui y fl t the applicatio baif no t sprays startin latn gi e Jul Augusr yo d an t repeatin treatmene gth monthlt a t y intervals until late October. Dimethoate at a concentration of 0.05$ active ingredient is mixed with protein hydrolyzate in a 1:10 ratio and applied to few branches of each tree. In this experiment, three treatments were applied at one-month intervals in August, September and October. Olive samples were taken at 0, 7» 14, 21 and 28 days after treatment £>r analysis. A fourth treatment was applied in Novembe treew fe provido t sn r o e ripe fruit r processinsfo l oi d gan extraction.
Extraction and Cleanup
The extraction procedure reporte Bowmay db n s modifieejtwa ^ aj.) ^(3 d and adapte oliVer fo doild san . Samples were extracted with wateo rt transfer dimethoat metabolites it d ean s intaqueoue oth s phase- Go . extracted oily materials were removed by petroleum ether. The aqueous layer was then shaken with 1O$ methanol in chloroform to extract dimethoate and its oxygen analog, dimethoxon. The extract was concentrated on a rotary evaporator prior to clean-up and analysis by gas chromatography. The remaining aqueous laye s evaporatewa r residudrynese o dt th d esan dissolved in acetone for thin layer chromatographic detection of water soluble metabolites.
Cleannip of the extract was carried out according to the procedure describe Stelley db Pasarelld ran a (2)methoe Th . d involved column chromatographic clean-u elutiod silicn po an l dimethoatf ange o d ean dimethoxon with acetone eluate Th concentrates . ewa rotara n do y evaporator prior to analysis by GLC. Extraction and clean-^up of fortified samples gave recoveries of 85-90$»
Gas Ghromatographio Analysis
A Varian Aerograph Model 2800 equipped with an alkali flame ioniaatio ni.dm m detecto .2 lon m d 8 used s gan colume r1. wa Th .s nwa and packed with 2^5 DECS on 80/100 mesh gas chrom Q. Inlet, column, and
24 detector temperatures were 225°, 200° and 230°C, respectively, and the nitrogen carrier gas flow rate was 60 ml/min. All "mg/kg" values were calculated on a weight basis (w/w).
Thin Layer Chromatographio Analysis
Pre-coated silic platel age s with fluorescent material were used. Several solvent systems for developing the plates were tried. A 3:2 chloroform:acetone mixturmose th t founs e suitablb e wa o dt e (stelled ran Curry, 4).
RESULTS AND DISCUSSION
Table I presents residue data of dimethoate and its oxygen analogs dimethoxon, in olives treated at three intervals. The total residue of the two chemical gives si eacn ni h case resulte Th . s indicated tharate tth e of decrease in residues was influenced by weather conditions. In the first treatment applied in August, the final residues (0.5 mg/kg) represented only about 3% of the initial level (15 mg/kg). In the Septembe Octobed ran r treatments finae ,th l residues represented about 6 and 13$ of the initial levels, respectively. The increasing oil contenolivee th f sto with tim havy ema e also contribute thio dt s effect coull sincoi de esloth w dowrate hydrolysif nth eo insecticidesf so . It is also important to note that in the three treatments, the level of dimethoxon gradually increased with time until it reached a maximum day4 athed 1 t san n starte decreaseo dt . Furthermore three th en ,i treatments, the dimethoxon level after 28 days was higher than that of dimethoate.
The hydrolysis product diraethoatf so e whic watee har r soluble were analyzed by thin layer chromatography. However, none of these metabolites was detected since their levels were belo detectioe wth n limit thud ,an s the attempt identifo st y them were unsuccessful.
Olives spraye Novemben di r were harvested seven days after treatment for eithe extractiol roi processingr no sevenwiaye Th . s intervas lwa selecte ensuro dt presence eth sufficienf eo t residue botf so h dimethoate and dimethoxon so as to study their fate under different processing conditions. Oil was extracted from the crop in a coramerc&l plant, and samples of both the oil and the remaining aqueous fraction were taken for analysis.
Resultanalysie samplel th oi f so givee f t so I sar Tabl n ni . eII evidens i t thamajoe tth r portio residuee th f naqueou o e foun s sth i n di s fraction. This is to be expected since both dimethoate and dimethoxon
25 are water soluble. Dimethoate residues in the oil and the aqueous phase constituted 5 and 60$, respectively of the initial level found in the fruits. A similar behaviour was exhibited with dimethoxon. The solid fraction resulting from the squeezing of olives may have contained additional residues. However, this fraction was not analyzed due to the difficulty encountered in the extraction procedure.
A sample of whole olives was processed by the traditional method of soaking in a brine solution until the fruits lost their bitter taste. The debittering process depends on the olive variety and requires from 7-30 days thin I .s experiment fruite ,th s were analyze day4 d1 s after soaking in brine solution. Table III shows the results of the analysis, and it is evident that soaking of the olives causes a sharp decline in residues. The level of dimethoate decreased from 10.5 to 0.10 rag/kg; lesoriginae th s f thao l% n1 leve lfrese founth hn di olive s remained after processing. Dimethoxon level also dropped sharply.
conclusionn I evidens i t ,i t that dimethoat readils ei y metabolized in olives durin maturine gth g proces treesn so . Processing of-the olives or oil extraction also results in sharp decline of the insecticide residues.
ACKNOWLEDGBMBNT
The author would like to express his deep gratitude to the International Atomic Energy Swedis e Agencth d hyan International Development Authorit their yfo r generous suppor thif to s research project.
REF3REWCBS
Pietri-Tonellie D . 1 Bazzi, ,P. f Santi,B. Residu. ,R e Reviews_ ,11 (1965). ,60 2. Steller, W.A., Pasarela, N.R. J. Assoc. Offic. Anal. Chemists 5JJ (1972\ 1280. . 3 Bowman, M.G., Beroza Leuck, ,M. , D.B Agric. .J . Pood Chem.^ ,16 (1968), 796. 4. Sbeller, W.A., Curry, A.N. J. Assoc. Offic. Anal. Chemists, 4_£ (1964), 645.
26 Tabl . eI Residue f Dimethoato s Dimethoxod ean Oliven ni s Treated at Three Intervals.
Sampling Residu (mg/kge* ) Interval, Days Dimethoate Dimethoxon Total
0 15.0 _ 15. 0 7 9.4 0. 56 9.96 First Treatment 14 3.6 0.90 4.50 (August) 21 0.46 0.82 1.28 28 0. 15 0. 35 0.50
0 12.4 - 12.4 7 7. 0 0.76 Second 7.76 Treatment 14 3.8 0.96 4.76 (September) 21 0.93 0.90 1.83 28 0.24 0. 53 0.77
0 13.0 - 13.0 7 10. 4 0. 75 11. 15 Third Treatment 14 6.2 1. 30 7. 50 (October) 21 1.8 1.25 3.05 28 0.85 0. 90 1.75
* Each value represents the mean of six analyses
27 Tabl . eResidueII f Dimethoatso Dimethoxod ean l ExtracteOi n ni d from Sprayed Olives Harvested Seven Days After Treatment.
Residu Oliven ei s Residue in Oil Residue in Aqueous Fraction rag/kg mg/kg mg/kg Dimethoate Dimethoxon Dimethoate Dimethoxon Dimethoate Dimethoxon
10.5 1.4 0.53 Trace 6.4 0. 37
Table III. Residue f Dimethoato s Dimethoxod ean Sprayen ni d Olives Harvested Seven Days After Treatment and Soaked in Brine Solution for 14 days.
Residue in Fresh Olives Residu Processen ei d Olives mg/kg mg/kg
Dimethoate Dimethoxon Dimethoate Dimethoxon
10. 5 1.4 0. 10 Trace
28 IN COTTONSEE CAKD AN E L RESULTINDOI G EROE MTH COMBINED APPLICATIODIMETHOATd an T DD P ENO
G.A ZORGANL .E M.Md Ian . AHMED Agricultural Research Corporation, Wad Medani and The Chemical Laboratories, Khartoum, Sudan
ABSTRACT
Cotton plants were treated with a combination of DDT and dimethoate under conditions of local agricultural practice to study the fate and magnitude of both chemicals in the cottonseed and related products. GLC and nuclear (using C-DDT) techniques were used. DDT residues in the crud averagel eoi d 0.115 mg/kg; mainl p,p'-DDs ya T while residuee th n si cake wer detectedt eno . Dimethoat dimethoxod ean crude werl th eoi n e ni 0.10.0d 3an 1 mg/kg respectively cake Th e. contained 0.14 mg/kg dimethoate and 0.01 mg/kg dimethoxon.
By simulating commercial oil processing in the laboratory using ^- fortified oil samples it was found that alkali treatment and bleaching removed only 1% of the total residue, while deodorization effected removal of 40-5052 of the residue.
INTRODUCTION
The largese Sudath s ni t African country wit aren ha abouf ao e ton million scjuare miles, of which more than one third is suitable for crop and pastoral farming. maiCottoe th n s casni h crop onlt ,no y because of its fiber value, but also as a source of oil and cake meal for human and animal consumption Gezirae th main e I ,.th n cotton growing area countrye inth croe ,infestes th p i d wit hvarieta insecf yo t pests which necessitates an ever-increasing rate of pesticide usage. Presently, the Gezira cotton receives an average of 6-7 sprays per season. The most widely used chemicals are DDT, monoorotophos , dimethoate, endosulfan and carbaryl (l). (Tabl . ConsiderableI) e amount dieldrinf so , aldrin, BHC and mercurial fungicides are also used for seed treatment of cotton prior to sowing.
The use of a mixture of DDT [l,l,l-trichloro-2,2-di-(4-chlorophenyl) ethane] and dimethoate [0,0-dimethyl S-(N-methylcarbamoylmethyl) phosphoro dithioatej at the rate of 1.0/0.4 lb a.i./feddan on cotton has been recommended for the past 15 years. On several occasions during the last
29 year0 1 s when sample marketablf so e cottonsee werl doi e analyse pesticidr dfo e residues, they were foun contaio dt (2)T levelw DD nlo ,f so (3) .earlien A r study has shown that residues ranging from 0.3 to 0.7 mg/kg in oil could result from spraying cotton with DDT alone or in combination with other insecticides (4). The present investigation was undertaken to determine the residue levels in cottonseed oil and cake of cotton plants treated with C-DDT/dimethoate mixture under condition commof so n agricultural practice Gezirae in th effec e Th .simulatef to d commercia processinl loi e th n go removal of DDT residues in cottonseed oil was also studied.
EXPERIMENTAL
Insecticides
Technical grade DDT was a gift from Shell Chemicals (Sudan) formulation factory. Analysi showeC GL followine y dsth b g composition:
p,p'-DDT 70$ 0,p-DDT 20$ Others
Dimethoate 99$ purity, a white crystalline solid was a gift from Montedison, Milano. DDT- G (specific activity 83«4 jiCi/mg) was purchased froRadiochemicae mth l Centre, Amersham, England chemicas It . l purits ya the p,p'-isomer exceeded 98$, as checked by GLC, TLC and liquid scintillation counting. The radiochemical (240 |iCi) was taken up in ethanol (10 ml) and stored at - 10 . Formulation bases essential for making up the emulsifiable concentrates of DDT and dimethoate were obtained from Shell Chemicals (Sudan).
The Crop;
submarginaa Thf o e s plowa t) lm selecte positio5 x 3 d( n ni Hawasha 249 in the Gezira Research Rarm. The whole Hawasha was sown during the period 21 - 30 July with cotton variety Barakat and the selected plot was since maintained under standard conditions of the Gezira. A total of 30 plants were marked to receive the experimental treatment.
Preparation of the spray mixture and application;
Technical DDT (432 mg) and dimethoate (174 mg) were dissolved separately, each in its formulation base (2 ml and 1 ml respectively). solutionTho etw s were then mixe rinsingd containerdan e th f so s with distilled water were added. Ethc.nolic-solution containing C-DD uCi0 T(6 )
30 was then quantitatively added to the emulsion and the volume made up to 60 ml with distilled water and thoroughly shaken. A blank base mixture (30 ml) was prepared and kept separately, for rinsing the sprayer bottle. Application was made 4 times at 2-week intervals, at times corresponding to those of actual practice.
Extraction and Clean-up;
At harvest, collected seeds were ginne ginnina n di g machin yielo et d 588 g of cottonseeds. Cottonseeds (500 g) collected from plants treated with C-BDT/dimethoate were finely groun blendera n di . Portiong 0 1 f so were placed in fibre glass thimbles and extracted for 4 hrs in a Soxhlet apparatus using hexane (b.p .extractl Al 67-6 • 9) s were pooled dan hexan removes e wa rotar s a wa n di ) yg evaporato0 (9 crude l th eoi d ran collected. Cottonseeds from untreated plants were processed similarly to serve as a blank. The material left in the thimbles after extraction was treated as the cottonseed cake for further testing.
For the analysis of DDT residues, the crude oil was cleaned-up by the method of Vierov et al. (5)« To clean-up the sample for dimethoate residu dissolves e wa analysis) g hexann 0 di (1 crude d ,l th ean eoi extracted with acetonitril ml)0 acetonitrile(8 e .Th e laye washes rwa d with fresh hexane (80 ml). The hexane layers were combined and extracted with fresh acetonitrile (80 ml) which was added to the acetonitrile already collected. The acetonitrile was removed in a rotary evaporato residue th d eran dissolvehexane-acetonl m 0 5 n di e (90:10). The extrac furthes twa r cleaned-u silica n columpl o age dimethoatd nan e residues were eluted with acetone. After evaporation and redissivins in little acetone sampl e analysisC , th GL reads ewa r yfo .
Analysis;
Gas chromatographic analysis for DDT residues was carried out in two laboratories using two different types of instruments. In each case at least 5 replicate samples were analysed. In Wad Hedani, analysis was carrie usint dou Carlga o Erba EC/G) Omm mode4 . x Colum lGl m l ( n was packed with 1.5$ SP 225 + 1-95$ SP 2401 on Suplecon AW-DMCS treated 100-200 mesh and at temp. 180 . Detector temperature was 300 and nitrogen ml/mincarrie0 ae t5 th s r.wa gas Khartoun .I m Chemical Laboratories analysi performes swa equippeO Tracea G n 0 do r56 d wit electron ha n capture "Tli detector and an all glass column (61 x K4" i.d.) packed wit OV-% h3 Chromosorn 1o b W-HP 80-100 mesh temperaturee Th . e th f so injection block, oven and detector were 200, 200 and 350° respectively. Carrie helius rga ml/min0 (6 m useds )wa .
31 Liquid scintillation counting of C-activity was carried out using a Beckman LS-255 spectrometer. Sectarian Ready-Solv Solution IV was the scintillator used countind ,an g efficienc 96%.s ywa
Gas chromatography for dimethoate residues was performed on P & M Mode 2 Hewlett-Packarl40 d Instrument equipped wit flamha e photometric detector operated in the phosphorus mode with a 526 mm filter. Column (60 cm x 4 mm i.d.) of borosilicate glass packed with 11$ DC-200 on Gas Chrom Q, pretreated with Versamid 900 polyamide resin, 60-80 mesh. Column, injection and detector temperatures 165, 250 and 160 respectively. Helium, hydroge werr ml/rain0 ai 55 e d d usen an an . flot da 5 2 w i rate75 f so
Simulated commercial processing procedures;
Fortification;
Crude cottonseed oil was fortified with p,p'- C (0.083juCi/mg) and inactive DDT to produce a final concentration of 10 mg/kg.
Alkali treatment;
vigorousls A wa sampl ) ml fortifief eo 0 y(1 stirrel doi d with 0.1N NaoH solution at 60-70 for 30 minutes. The amount of alkali used was in 20$ excess of the free fatty acid content of the oil. The mixture was then centrifuged and washed three times with water. Aliquots of the treated oil were counted in LSC and also analysed by GLC.
Bleaching;
The alkali refinetreates wa l doi with 0.5$ Fillers earth (same material used by a local proceasing plant) and incubated at 80-82° for s centrifuge30wa minutesl oi e removo Th dt . adsorbene eth aliquotd tan s of the bleached oil were similarly analysed. •
Jeodprisation;
The bleached oil was heated to 200-220° and a slow stream of steam was injected into the oil, at 23 mm Hg pressure, for 4 hrs. The deodorised oil was cooled to room temperature and analysed.
In a separate experiment, C-DDT-fortified crude oil (10 ml) was subjecte deodorisatioo dt n onlanalysedd yan .
32 RESULTS AND DISCUSSION
The residue werl oi es e mostlfore foun th p,p'-DDT f th mo n di n yi . Only negligible amountwerE DD e f so found . Ther s gooewa d agreement between the result variouf so s replicatelaboratorieso tw e th n si , givin gmeaa n residue leve 0.11 f crudo n li l 5eoi mg/k g (Table II) radio-methoe .Th d also gav residuea e concentratio 0.11f o n 5 mg/kg excellenwhicn i s hi t agreemen resultsC t GL wit e residue hth Th . e figures (obtaine GLCy db ) were corrected for a background level of 0.003 mg/kg found in control samples. No residues in the cottonseed cake could be detected.
Simulated commercial procedure alkalf so i refinin bleachind gan g had little leveeffece th f ln o C-DDt o T residue (Tabll oi n ei s III). However, deodorisation removed 41% of the radioactivity in the fortified sample. When fortifie ds directl crudwa l eoi y deodorisede th f o ^ ,51 residue coul removede db , confirmin significance gth thif eo s process in reducing residue level edibln i s e oils resulte generan i Th . e sar l agreement reportewito wh h) (6 thosd l neaSaha f eo t rae complete removal of DDT and BHG from rape seed oil by deodorisation.
It may be concluded that initially low residues of DDT would result from the recommended practice of DDT/dimethoate application on cotton. These residues are considerably reduced throu^i the commercial processing leadin ediblo gt productionl eoi . Thus, there exist reasonablsa e margin of safety for the use of DDT on cotton with regard to residue levels in oil and cake. The absence of DDT residues in cake reflects the efficiency of petroleum solvent extraction worts i t hI . mentionin g tha numbeta f ro oil mills in the country use pressing methods in which case the cake produced is likely to contain measurable amounts of DDT residues.
Residue dimethoatf so oxos it n d werean e detecte crude th l en oi di at level 0.1f so 0.0d 3an 1 mg/kg respectively cake Th e. also contained residue similaf so r magnitude (Table IV).
ACKNOWLBDGBME»T
The authors are thankful to the IAEA for partially supporting this work through research contract 2152/RB. They also express their deep Gelmett. gratitudA . Dr Jbntedisonf o io et ,supple Milanth f r yo ofo dimethoate and for carrying out the gas chromatographic analysis of its residues. Special thanks are due to A.M. El Hindi for his interesting discussion held san p durin phasel gal thif so s work.
33 REFERENCES
] Lis [l recommendef o t d pesticides (1980)} Agricultural Research Corporation, Wad Medani, Sudan ] AHMED[2 , M.M. (1976)$ Unpublished data ZORGANIL E ] [3 , K.Ad G.A.an . ABBADI (1978)} Proceeding Symposiuf so m on Crop Managemen Sudann i t , February preparationn 197(i 8 ) [4] EL ZORGANI, G.A.; Pesticide Science, 6_, 457 [5] DAN VIEROV and N. AHARONSON (1978); J. Ass. Off. Anal. Chem., 2, 61, 253 ] SAHA[6 , J.G., M.A. NIELS5J A.Kd Jan . SUMNER (1970) Agr. }J . Food Chem. . (l)8 ,1 43 ,
TABLE I; Annual Usage of Pesticides in Cotton in Sudan
Pesticide Quantity (ibs active ingredient)
DDT 3x 106 Dimethoate 1.7 x 106 £. Endosulfan 1.4 x 10 Monocrotophos 1 x 106 Carbaryl 3.5 x 105 . 6 Toxaphene 1 x 1n0 Parathion-methyl 2.5 x 105 BHC 3.0 x 104
TABL : EII C-DDT Residue Cottonseen si Cakd an e l dOi
Material DDT (rag/kg)
LSC GLC
Crude oil ' 0.108 0.110 0.112 0.120 Cake n.d.
n.d. = non detectable
34 TABLE III; Effec f Commerciao t l Processin n go C-DD T n Cottonseei l dOi
•treatment % Radioactvity retained in oil
Alkali refining 95 Bleaching <3 Deodorisation 52
TABL ; DimethoatEIV e Residue Cottonseen si Cakd an e l dOi
Material Residues (mg/kg)
Cottonseel doi Dimethoate 0.13 Dimethoxon 0.010
Cottonseed cake Dimethoate 0.14 Dimethoxon 0.010
35 MONOCROTOPHOS RESIDUES IN COTTONSEED AND RELATED PRODUCTS
Jarai. M l QURESHI SATTAR. ,A M.Hd ,an . NAQVI Nuclear Institut Agriculturr efo Biologd ean y Faisalabad, Pakistan
Monocrotophos 3-(dimethoxyphosphinyloxy)-N-methyl cis-crotonamids eha teen firs e reporteth te b systemio dt c foliar insecticide capablf eo controllin cottol gal n pest economif so c importance including cotton leaf worm (Spodopitera), spiny bollworm (Earias), cotton bollworm (Heliothis), red bollworm (Diparophis), pink bollworm (pectin ophora), spider, mites, aphids, jassids, thrips, white flies, beetles and weevils (l). Monocrotophos also controls cotton pests which are resistant to chlorinated hydrocarbon otheo t d rs an organophosphoru s compounds (2). The purpose of the present investigation is to determine the magnitude insecticide ofth e residue cottonseee th n si d products under local condition agriculturaf so l practice.
Seeds of cotton variety B577 were sown in the regular growing period observing all regular agricultural practices. During the development of foliage the crop was sprayed four times with monocrotophos (500 ml/ha) at one week intervals. The plants were left to maturity and the harvested seeds were ginned. Oil was extracted according to a standard procedur residued an ) e(3 s were determine spectrophotoa y db - metric metho usin) d(4 g vanadomolybdate reagent (5).
Tabl showeI residue sth e level cottonseen si d products derived from contro treated lan d plants "backgrounde Th . " residue presumable sar y the product of previous applications. It is maintained that the high residue level in the crude oil is related to the lipophilic nature of the chemical. linn i Thi es si wit findinge hth s reporte leptophor dfo s residue cottonseen si d product (7)) s(6 .
37 TABL ; EMonocrotophoI s residue cottonseen si d products
Treatment Residues (mg/kg)
Seed Oil Cake
Control 0.45 0.54 0.40
Sprayed with 0.75 2.10 0.42 monocrotophos
ACKNOWLEDGEMENT
The authors wis PAE e their thano th ht fo OIAE e d rkth A an technica financiad lan l support. Thealse yar o thankfu SHELo lt L Insecticide, UK for providing analytical grade monocrotophos, Dr. S.H. Mujtata Naqyi, Director, Mr. M. Amin, Farm Manager, NIAB, Faisalabad for field and laboratory facilities.
RhlKKKENGBS
[l] Anonymous; (1969), Nuvacron, CIBA, Switzerland [2] Dyson, P; (1968), J. Agric. Pood Ghem., 1^6, 28 [3] Horwitz, W. (Ed.); Official Methods of Analysis, Assoc. Off. Anal. Chemists, 12th ed., Washington, D.C. (1975) ] Pesticid[4 e Chemical News Guide. Pood Chemical News Inc., Washington, B.C., 20013 (1974-1977) [5] Hansan, A; (1950). J. Sci. Pd Agric., 1., 172 ] Hassan[6 Zayed, ,A. , S.M.A.D Mostafad .an , I.Y. (1979). IAEA-218, Technical Document Series, Vienna3 6 . ,p [7] Qureshi, M.J. (1979)? IAEA-218, Technical Document Series, Vienna, P. 59.
38 CARBARYL RESIDUES IN MAIZE AND PROCESSED PRODUCTS
Jami. M l QURESHI SATTA. ,A R (Jr. M.Hd )an . NAQVI Pood Science Division Nuclear Institut Agriculturr efo Biologd ean y Paisalabad Pakistan
ABSTRACT
Carbaryl residues in two local maize varieties were determined usin gcoloritnetria c method significano N . t differences were observed for residues of the two varieties which ranged between 12.0 to 13.75 mg/kg in the crude oil averaged ,an d 1.0 0.6d 4an 7 flou e mg/kcakd th ran n eg i respectively. In whole maize plants, carbaryl residues declined to approximatel mg/ky2 day5 g3 s after treatment. Cookin aqueousn gi , oil or aqueous-oil media led to 63-83$ loss of carbaryl residues, afte minutes0 r3 .
INTRODUCTION
Maize bein gcereaa l ric calorien hi importans si higa s hta yielding foo fodded dan r grow s cropi t nI . ove aren r a 65,00 f ao n i 0a h Pakistan graie . Th uses ni d mainl humas ya n food with onl smalya l part destine live-stocr dfo k feed. Consumptio corw ra n f ncobso , roaste boiledr do becomins ,i g more popular now-a-days. Corl noi serve cookina s sa g mediu manr mfo patientyr fo food d san s suffering from coronary diseases.
Therwida s ei variet Insecf yo t pests whic completely hma y destroy maize plantations. Maize borer consideree sar mose dth t injurious pests in Pakistan. For control purposes, the oarbamate insecticide, carbaryl has been found to be very effective (l). Carbaryl (l-napthyl-N-raethyl carbamate) is a broad spectrum insecticide with low mammalian toxicity (2). The metabolism of carbaryl has been extensively studied in cotton plants, potatoes, insects and soils. The fate and persistence of carbaryl residues in milk, fat and meat of lactating goats were also reported (3). Because of its low toxicity, residue tolerance range th 5-1 f eo n s i 2 mg/kg have been recommended (4).
39 Carbaryl residues were foun vegetablen di fruid san t crops, thus finding thei int y humae rwa o th n diet (5) chromatographis .Ga c (6), and colorimetric methods (7) were employed for the determination of carbaryl residue field-treaten si d corn plants. Carbaryl residues in maiz cottod ean n crops were also determined radiometrically (8,9). Generally, pesticide level reducee b foon n si cookindca y db g (10,11,12,13). Dieldrin residues in bacon could be reduced by pan frying and baking (14,15). Residues of raalaoxon, fentrothion and chloryrifos methyl were reduced substantiall boilingy yb , while cyanofenphos, leptophos and carbofuran residues increased in boiled samples, presumably due to los watef so r (16).
The present work provides dat carbaryn ao l residue maizn si d ean related products as well as cooking effects on carbaryl-fortified samples.
MATERIALS AND METHODS
Neele Akbard man a varietie maizf so e grain were sowa n ni prepared plot. Plants were left to grow under field conditions regarding thinning, irrigation and fertilizer application. When the floral parts developed, they were sprayed with 85/6 carbaryl (2 kg/ha). The application was made four times at one week intervals, as practised in the field by pouring the chemical suspension in the axils of the leaves. On harvest, corn oil was extracted in soxhlet apparatus and corn flour s preparewa grindiny db whole gth elaboratore seedth n si y mill. Grains of maize were also sown in pots and the plants were allowed to grow in a green house groupo fw , s (each comprising five 4-weekold plants) were spraye duster do d with commercial carbaryl (85$ kg/ha2 t )a . Carbaryl residues were determine methoe th Johnsof y do db n (7). is based on the alkaline hydrolysis of carbaryl and colerimetric determination of the resulting 1-naphthol after coupling with p- nitrobenzenediazonium fluoborate as carcinogenic agent. In this study hydrolysie ,th s tim extendes e wa minute 0 1 o dt s (recovery
Green house-grown plants were picke weeklt da y intervalr sfo five weeks, dried, ground, powdere stored dessicatorda an n di r ,fo determination of carbaryl residues.
A local survey of public canteens and hotels was made to obtain information concerning regular cooking practices, cooking media, temperatur rangesH p d ean , encountere different da t stagef so preparatio conventionaf no l foods. Carbary methylenn li e chloride was added to water, oil or oil-water (l:l) buffered system (pH 4.2) to produce an end concentration of 2mg/kg. The water, oil and oil- water buffered systems were heate 100°t da , 250 110d °an ° respectively, for 10, 20 and 30 minutes and oarbaryl residues determined as previously described. 40 RESULTS AND DISCUSSION
Carbaryl residue corn si n oil, flou cakd showe ran ear n ni Table I. Statistical analysis revealed no significant differences in th maizeo residuetw ee varietiesth f so containel Oi . highese dth t residue levels.
Table II shows carbaryl residues in whole maize plants. Following treatment, a gradual decline of residues was observed till the fifth week; carbaryl concentration decreased to about 2 mg/kg. During the first three weeks dusted plants contained higher residues than sprayed plants decline amoune Th .th residuef n to ei s with lin n timi es ei with the expected chemical and biological degradation of the insectide. Percentages of loss of carbaryl residues in heated water, oil and oil-water buffered medi presentee aar Tabln di e III. Reduction of the insecticide residue, following cooking is in conformity with previous findings (10, 11, 12, 13). Maximum loss of carbaryl was observed in water. Reduction in carbaryl residues may be attributable to degradation, volatilization and/or co-distillation.
ACKSOWLEDGBHBTTS
The authors wish to thank Dr. F.P.W. Winteringhara and Prof. A. Hassan for guidance and valuable suggestions. They are also thankfu S.H. Dr * o lHujtabt a Naqvi, Directo Muhanma. Mr d ran d Amin, Farm Manager, NIAB, Faisalabad providinr ,fo g laboratory facilities and technical assistance.
RKMiiHENCKS
] Unio[l n Carbide Corporation, Technical Information Report, Agricultural Product Servicesd san , Salinas, Gal. (1973)A US , . ] LBELING[2 , N.C., KRISHNA, J.G., Bull. Ent. Soc. America (37),£ , 163 (1963) [3] ABD-EL-HAKID, P.M., M. FARGHALY and L.M. AFIFI, Technical Document Series, IAEA-218 (1979)9 2 . ,p [4] KIJHR, R.J., J. Agri. Food Chem., 18, 1023 (1970) [5] MOLOZHANOVA, B.C., Gig. Primen., Toksikol. Pestits. Klin. Otravlenci, 8, 170 (1970) LAL. R ] DHALL,d [6 Colorimetrian . ,P o determinatio carbaryf no l
residue fieln si d treated corn. Journa A.O.A.C.e th f lo t ,5 1095-1099 (1971) [7] JOHNSON, D.P., Journal of the A.O.A.C., 74, 283-286 (1964) ] [8 ZAYED, S.M.A.D., S.A. MANSOUR, I.Y. MOSTAF . HASSANA d Aan , Technical Document Series IAEA-218 (1979)3 1 . p ,
41 [9] QURESHI, M.J., Technical Document Series IAEA-218 (1979), P« 21 [10] RITCHEY, S.J., R.W. YOUNG and B.O. ESSARY. J. Agr. Pood Chem., 20 (2) (19721 ,29 ) [11] REINEHT, R.E., 0. STEWART and H.L. SEAGRAM, J. Fisheries Research Boar Canadaf do (5)9 , 2 (1972 5 ,52 ) [12] LISKA, B.J., A.R. STEM W.Jd Pan . STADELMAN Pood Technol., 21, 435 (1967) [13] SMITH, W.E., K. PRANK and M.E. ZABIK, J. Fisheries Research Boar Canadaf do (5)0 ,3 (19732 .70 ) [14] MORGAN, K.J., M.E. FUN. ZABIK Kd Kan Poultry Science (19720 47 , ),51 [15] YADRICK, M.K., K. FUNK and M.E. ZABIK J. Agri. Food (19711 Chem.49 , ),17 [16] TALEKAR, N.S., L.T. SUN, E.M. LEE, J.S. CHEN, T.M. LEE and S. LU Journal of Economic Entomology, 70, 689-692 (1977)
TABL : CarbaryEI l residues (mg/kg products maizit n ) i d ean s
SAMPLE Variety Treatment Flour Crudl eOi Cake
Control 0.32 0.24 0.37
Neelem Carbaryl- treated 1.03 12.00 0.67
Control 0.33 0.27 0.38
Akbara Carbaryl— treated 1.04 13.75 0.66
Dat meae threaf ar n o e determinations
42 TABL ; CarbaryEII l residues (mg/kg wholn )i e maize plants (Neelem variety)
Treatment Days after treatment
0 7 14 21 28 35
Control 0.20 0.22 0.19 0.23 0.200.22
Sprayed 0.20 12.22 6.11 3.67 3.672.26
Dusted 0.20 18.35 8.70 5.93 3.461.80
Data are mean of three determinations
TABLE III; Effec cookinf to carbaryn go l residues
% los carbaryf so l residue aftes* r Treatment 10 rnin 20 min 30 rain
aqueous cooking 63.1 69.6 83.1
cooking in oil- water buffered 48.6 51.4 69.8 system
cooking in oil 44.2 52.3 62.8
earbary* l concentratio spiken ni d sample mg/ks2 100$s g( )
43 CARBARYL RBSIDOE COTTONSEEN SI D PRODUCT PHILIPPINEE TH N SI S
Ptolip PABL. aE O Natural Science Research Centre University of the Philippines Quezon City 3004* Metro Manila Philippines
ABSTRACT
Residues of carbaryl in cottonseed products were determined by spectrophotometry. Carbary cakd l an eresidue l weroi e n 0.8si 0.0d 3an 4 mg/kg respectively.
Parallel experiments with G-carbaryl gave comparable results. ^C-carbary cakd l an residuee l weroi en si 0.4 0.1d 2an J mg/kg respectively.
INTBOIPCTION
Pest control chemical food san d additive essentiae sar adequato lt e food production, manufacture, marketing storaged ,an . However, without continuing surveillance and intelligent control, some of those that persis foodstuffr ou n ti s coul timet da s conceivably endange public'e rth s health.
Cottonseed is a main source of oil in many countries. Seventy-five percent of the world's supply of conttonseed is processed to obtain oil and meal lattee ,B»sth e th ri f beinoossaoo e gon n protein supplemenr tfo dairy animals, swine and poultry.
Carbaryl is one of the many pesticides used in large cotton farms Philippinese inth , where pesticide tolerance consideret no e sar d dan in many cases the nature and magnitude of residue(s) remain unknown.
Hassan et al. (l) reported that in cotton the residues of leptophos (an organophosphate), obtained by radiometric method, were: 0.34 mg/kg in cottonseed; 0.8 2 0.2oild e mg/kan th ;4 n cakege i mg/k th .n gi
It is aimed to determine the residues of carbaryl in oil and cak speotrophotometriy eb radiometrid can c techniques under conditions prevailing in the Philippines.
45 MATERIALS AND METHODS
Cultivation, application, extraction and residue analysis;
A. Non-nuclear
Deltapine variety of seeds was planted in an experimental garden divided into two plots, one serving as control. In the treated plot, carbary sprayes rate lwa 14.f th eo t d0a mg/10 ml/plant. This concentration is use actuan di l practic locae th ln ei cotto n farms. Ammonium sulfate was applied before planting and before boiling periods. 0.71 inches of rainfal recordes lwa d since planting time. Carbaryl residue cottonn si - seed, oil and cake were extracted and determined according to standard . 3) procedured an 2 , s(1
B. Nuclear
Carbaryl (napthyl-1- C), Sp. act. 3.11 mCi/g was synthesized by Prof PesticidHassae . .A th t na e Toxicology Laboratory, Regional Radio- isotope Centre, Cairo, Egypt. C-carbaryl (6.7mg/plant) was dissolved in a small amount of acetone and the volume raised to 10 ml by adding water. The chemical suspension was sprayed on the leaves of cotton plants. Sprayin dons gwa e three time two-weet sa k intervals bolle Th .s were harvested upon maturity. Extractio determinatiod nan residuef no s were made as previously reported (4)» (5).
TABLE I; Residues in cottonseed oil and cake by spectrophotometr radiometrd yan y
Residue (mg/kg) Sample Spectrophotometry Radiometry
Oil 0.83 0.42 Cake 0.04 0.15
Data are mean of 4-5 determinations
46 .DISCUSSION
Carbaryl residues in oil and cake are shown in Table I. Higher concentration carbaryf so oiln li , usin spectrophotometrie gth c technique may relate to higher application rates. When applications irere made at monthly intervals, lower residue d cakan s e l wer(5)oi e« e founth n di In general, residues reported in this investigation are unlikely to presen healta t h consumerhazare th o dt .
ACKNOWLEDGEMENT
The author wishe thano st F.P.W. kDr . Winteringha valuablr mfo e suggestions; Dr. A. Hassan for synthesizing C-carbaryl; the International Atomic Energy Agency, U.P. Natural Science Research e Centrth d ean Philippine Atomic Energy Commission for their financial and technical assistance.
REFKHBNCBS
[l] HASSAN, A., ZAYED, S.M.A.P. and MOSTAPA, I.Y. ; Trace contaminants of agriculture, fisheries and food in developing countries, IAEA Vienna (1976), STI/PUB/4549 5 . ,p ] Officia[2 l method analysif so s (Associatio officiaf no l analytical chemists, Washington, D.C. 1970), Eleventh Edition ] JOHNSON[3 , D.P. Assoc. ;J . Off. Agr. Chemists, 4J_, 283-285 (1964) ] ZAYED[4 , S.H.A.D., MANOUR, S.A., MOSTAPA, I.Y HASSANd .an ; ,A. Trace contaminant agriculturef so , fisherie food developinsn an di g countries, IAEA Vienna (1976), STI/PUB/4549 8 . ,p ] QURESHI[5 , M.J Radiotrace.; r studie pesticidf so e residue edibln si e oil seed related san d products. IAEA-218 (1979), Technical Document Series, p. 21.
47 DOT RESIDUES IN GROUNDNUT AND CHANGES IN DURING PROCESSIN GROUNDNUP GO L TOI
RAGHU. K , N.B.K. MURTHPBRREIR. J d Ian A Biolog Agriculturd yan e Division Bhabha Atomic Research Centre Bombay 400 085 INDIA • ABSTRACT
C-residu.es were not detected in oil or seedcake of Spanish Improved and TG-9 groundnut varieties which were earlier treated 14 / with C-DDT. However, 0.02 0.03d 1an 3 wer E mg/kDD e f gfouno d in Spanish Improved and TG-9 varieties respectively. Crude groundnut oil fortified with 14C-DD subjectes Twa simulateo dt d commercial processing procedures. Alkali refinin bleachind gan g procedure effeco n d n tso ha the residuesremova. C f lo , while deodorisatioe n th remove f o % d61 residues. After deodorisation only 4«3$was identifie DOTs da . Commercial processin DDD-fortifier o E DD f go showel doi d that deodorisation effected remova residuese mosth f lo f directo e Th . t deodorisatio bleachef no d groundnu fortifiel toi d D witOD hr o DOT E ,DD confirmed the efficacy of deodorisation procedure in removing the residues.
INTRODUCTION
Organochlorine insecticides lik stile e ar DDT lC bein,3H g used in Indi publir afo c healt agriculturad han l purposes direco t e tDu . unintentionar o e us l contamination, som thesf eo e residue finy sma d thei inty yieldinl rwa ooi g plants showe) (l .e . dth Bruc al t e translocation of some chlorinated pesticides from treated soils to oilseed plants. Chaudry et al. (2) had shown the distribution of chlorinated pesticides in soybean seed and oil. We have shown the presenc isoraer f especialleo H HC f so y B-isome groundnun i r l toi extracted from kernels of HCH-treated plants (3). Studies of the effect commerciaf so l processin pesticidn go e residue edibln si e oils were reporte variouy db s workers (3f4|5|6).
Recentl ) showe (? widespreay e . dKalrth al t ae d appearancT DD f eo and BHC residues in various food stuffs. The present study was made to determin seedcakd an residuee el th groundnuf oi eo n si t treated with
49 T followinDD g common agricultural practices. Alseffecte oth f so simulated commercial procedures on the fate of DDT and its metabolites, werE DD e d studiean D evaluato DD dt extene eth removaf to residuesf lo . The following abbreviation usede sar : DDT; 2,2-bis-(p-chlorophenyl)-
1,1,1-trichloroethane (pfp'-DDT); DDD; 2,2-bis (p-chlorophenyl)-!,!- dichloroethane (p,p'-DDD); DDE; 2,2-bis (p-chlorophenyl)- 1,1-dichloro- ethylene (p,p'-DDE).
MATERIAL METHODD SAN S
Field experiments;
Two groundnut varieties Spanish Improved (oil content; 49»9%) and TG-9 (oil content: 53.5$) were grown in field. The plants (15 of each variety) were treate recommendee th dt a wit T hDD d Ibs/acr 5 2 rat f eo e dust% a5 s , simulating local agricultural practices orden I . obtai o rt n 5% dust, a commercial preparation containing 50$ technical DDT was diluted with inert talc powde uses r(a factories)n d i calculateA . d amount was taken in a spray bottle and benzene was added. G.DDT (sp. act. 29.? mCi/m mol obtained from the Radiochemical Centre, Amersham) in benzenems also added, stirred well and the solvent was allowed to evaporate. Thinon-radioactivf o sg m amounte 3 0.0d 6. an o 1dt g T m eDD of C-DDT (equivalent to ca. 1 jtiCi) per plant. The dust was applied to leaves usin smalga l amoun watef to carriers ra .
Sample preparation, extractio analysisd nan ;
The groundnut pods were harvested and dried in sunlight and the shells were separated from kernel by hand. The oil was extracted from the methokernee s extracteth wa Thompsof y l do lb . (8) oi al e d.t Th ne in petroleum ethe partitioned ran d with acetonitrile. Radioactivitn yi oil, petroleum ethe acetonitrild ran e fraction determines swa n di Beckman LS-10O scintillation counter.
GLG analysis;
The acetonitrile fraction was extracted with petroleum ether for GLC analysis in a Toshniwal model RLO. (Toshniwal Instruments, Bombay). The glass colum packes nwa d wit SE-3$ 3 h chromosorb-n 0o W (80-100 mesh). The operating conditions were: Column temperature 190 C; detector temperature 195 G; injection port 210 C, carrier gas was nitrogen at a flow rate of 120 ml/min. The analyses were repeated with another column 10$ DC-200 on chromosorb Z (60-80 mesh).
50 TLC analysis;
Thin layer chromatograph dons nonwa n eo D -DD d an DDTf yo E ,DD activated silic platel age s impregnated with fluorescent indicator grsen (N-Woelm, Eshwege, Germany spote th sd wer)an e visualised unde lightV rU .
Of several developing solvents, a mixture of n-hexaner acetone, methanol
and diethylamine (100:1:1:1) gave good separation. Rf values of DDT, werD DD e d 0.69an E ,DD 0.8 0.5d 5an 0 respectively.
Seedcake;
The seedcake after solvent extraction was air dried, pondered and subjecte combustioo dt biologicaa n ni l oxidizer (BMO) (Harvey Instrument Corp., USA determinatior )fo f no C-activity .
Iparallena l experimen powderee th t d blende s seedcakwa ) g d 5 e( Sorvaln i ) ml l NaCM 0 Omnimixe wit5 l(8 h0. minute5 r fo r s followed minute0 3 y b vigorouf so s shaking contente Th . s were centrifuget da minutes 0 petroleu2 l m r o 1700fo Tw .m 0mrp ether were e addeth o dt supernatant and the mixture was shaken for 30 minutes and kept over- nigh root ta m temperature. Aliquot petroleue th f so m ether layer were possiblr fo analyze C GL e y recoverdb bounf yo d residue seen si d protein.
Effect of simulated commercial processing procedures;
G-PDT; Twent crudl ym e groundnu obtainel toi d fromilll moi s were fortified with 1 mg/kg ^C-DDT, and stirred with 0.1N NaOH at 60-70° fominutes0 r3 aci$ amounexcese e 20 th Th d . alkaln f f tsi o o s iwa value (9). The mixture was centrifuged and washed several times with water to obtain clear oil. The alkali treated oil was bleached with 0.5$ activated charcoal and bleaching earth (l:l) at 80-82° C for 30 minutes with vigorous stirring. The bleached oil was centrifuged and werl m e0 1 deodorize heatiny db 220-240o gt passind an °C g slow steam under vacuuhours4 samplesr l mfo Oi . , after each treatment were analyzed for 14C_activity.
DDT, DDE and DDD; DDT, DDE or DDD-fortified oil was subjected to commercial procedures. Following each treatment oil was partitioned between petroleum ether and acetonitrile. The acetonitrile layer was extracted with petroleum ether and the residues were determined by GLC. In a parallel experiment the fortified oil was directly deodorized.
RESULT DISCUSSIOND SAN S
obtainel Theoi d from kernel f so CLDDT-treate d t plantno d sdi sho y wC-activityan 1 4analysiO GL . petroleuf so m ether extractd sdi
51 not show any detectable residues as DDT confirming the above finding. However analysiG ,GL s showe presence dth 0.02f eo 0.03d 1an 3 mg/kE gDD in oil of Spanish Improved and TG-9 varieties respectively. This is probably related to the presence of 1.96$ DDE and 3.0$ ODD as impurities originae inth l preparation shows A . radioactivit y nb y measurements, the metabolic formation of DDE from DDT is unlikely. .Analysis of the seed cake of both varieties, similarly revealed the absence of C— activity analysiC GL . petroleuf so m ether extract seer so d protein also showed no detectable residues as DDT, DDE or ODD.
Althoug residueT DD o hn s were foun oiln di effece ,th f to commercial processin ggroundnun i procedure T fatDD e l f th toi eo n so was studied in the likelihood of some residues accumulating under different conditions. Alkali refining and bleaching had no effect on C-residues and TLC showed that the parent compound was not much affected (Tabl . DeodorizatioeI) radioactivitye nth removef o $ d67 , leaving only 4«3$ DDT and 18.2$ DDD. Initial experiments showed that deodorisation at 200-220 removed 34$ of C-residues, versus 67$ at 220-240°. Deodorisation at 190° for 4^2 hours removed only 20$ DDT, whil coul$ e70 removee db d durin hourg5 250°t sa C (10). Saha (ll) showed almost complete removal of C-DDT from rapeseed oil by a direct deodorisation procedure.
It must be mentioned that although steam was passed in our experiments actuae ,th l commercial conditions simulatede b coul t dno . Nevertheless resulte ,th s indicate that improved deodorising conditions may lead to near complete removal of residues.
The effects of commercial processing procedures on DDE and DDD are shown in Table II. Deodorisation was found to be the most effective treatmen removinn ti (TablD residuege DD mos th d ef t o an DDTf III) so E ,DD .
ACKNOWLEDGEMENT
The groundnut plant fielr sfo d experiments were kindly provided by Mr. S.H. Patil. We thank Mr. C.V. Sawant for his technical assistance.
52 TABLE I; Effect of commercial processing procedures on 14,C..DD groundnun Ti l toi
Percent Percent Procedure radioactivity radioactivits ya retainey db processed oil DDT DDE DDD
Alkali refining 97.8 87.1 1.5 n.d. Bleaching 100.1 89.6 0.5 2.0 Deodorisation 33.3 4.3 1.0 18.2
n.d. = non detectable
TABLE II; Effect of commercial processing procedures on DDT? groundnun i anD dDD l toi
Percent DDE retained Percent DDD retained Pr
Alkali refining 104.0 97.3 Bleaching 85.0 76.7 Deodorisation 26.7 34.0
TABLE III; Rffec direcf to t deodorisatio DDTn no E ,DD and DDD in groundnut oil
Compound Percent remaining in oil after deodorisation
DDT n.d. DDE 14.0 DDD 6.7
detectabln no n.d= . e werD DD e d addean E DDTdDD , separatel thren yi e different experiments
S3 RBPERMCBS
] BRUCS[I , W.N., DECKER, G.C., WILSON, J.G. Econ. ,J . Entomol., (19669 17 , ) 52 ] CHAUDRY[2 , M.M., NELSON, A.I., PERKINS, E.G., JAOCS, 55. 851 (1978) [3] RAGHU, K., MENDES, M.G., MURTHY, N.B.K., FERREIRA, J., Radiotracer studies of pesticide residues in edible oilseeds and related products, IAEA-218, Technical Document Series, Vienna (1979), P- 3 [4] ADDISON, R.F., ZINGK, M.E., ACKMAN, R.G., SIPOS, J.G., J. Ass. Off. Anal .(19781 Chera.39 ), ,^ ] GOODING[5 , G.M.B., Chem Indd .an . (London) (19664 ,34 ) [6] MOUNTS, T.L., EVANS, G.D., DUTTON, H.J., COWAN, J.G., J. Ass. Off. Anal. Chem., 46, 482 (1969) [7] KALRA, R.L., CHAWLA, R.P., DHALIWAL, G.S., JOIA, B.S., Proceedings Symposiue th f o Nuclean mo r Technique Studien si Metabolisf so m Effect Degradatiod san Pesticidesf no 19-30. ,p , DAE, Bombay (1978) ] THOMPSON[8 , N.P., WHEELER, W.B., NORDEN, A.J. Agr. ,J . Pood Chem., 18(19702 ,86 ) ] India[9 n Standard Method Samplinf so Tesd Oilr Patsd gan fo t san , 1£, 548 (Part I), 1964, ISI, New Delhi (1975) [10] PARSONS, A.M., Pesticide residues in fats and other lipids, p.243-293, in "Progress in the chemistry of fats and other lipids" (ed. R.T. Holraan), Pergamon Press, Oxford (1970) [II] SAHA, J.G., NIELSEN, M.A., SUMMER, A.K., J. Agr. Pood Chem., 18 43 (1970)
54 14 PATE OP TECHNICAL AND C -LABELLED BHC IN RICE GRAIN Tong-ftrd Su-Raan E N eLE a KI
Environmental Chemistry Laboratory Korea Atomic Energy Research Institute Seoul, Korea
ABSTRACT
The fate of BHC in paddy rice was investigated under conventional agricultural conditions of Korea by means of gas chromatographic and radiometric techniques.
Applicatio controe technicath f n o r ricf lo fo eC stelBH m borer at the first generation time resulted in a residue level of 0.02 mg/kg in brown rice while the application at the second generation time in- crease levee dth 0.0o lt 0.1- 6 8 mg/kg partitioe Th . n ratioC BH f so residues into polished rice grai brad nan n were 20:3 8:9d r 0an fo 2 100d $an $ polishing70 s respectively. Washin polishef go d rice removed 60-69$ of BHC residues while cooking effected removal of only 7-25$. maintaineIs ti d that polishin washind gan g pla importann ya t roln ei removin residuesC gBH . Following applicatio ^-(Uf no - C)-BHo Ct rice plants, onl radioactivitye th 2.8f o $ recoveres ywa ricn di e stra graind wan .
INTRODUCTION
BHC (benzene hexachloride, hexachlorocyclohexane) has been used in Korea since 1953 for crop and forest protection. Because of its persistent nature, great concern has been expressed in relation to accumulatio environmene th n ni possibld tan e apprearanc fooe th d n ei chain.
Studies on the behaviour and transport of BHC in the environment, crop production (l), (2), (3) and food processing (3), (4), (5)» (6) were reported by several workers. Though BHC is currently used in paddy rice under good agricultural practice deemes i t ,i d necessar studo yt y the magnitud fatd residuee f an ebrano d graine an th .l n ,si oi
55 MATERIALS AND METHODS
Field experiments
An experimental paddy field at Kyonggi area (central part of 2 the peninsula) was divided into 9 equal experimental plots of 300 m each. A second fiel similarls dwa y divide Honart da a (Southwest coast) area. Paddy ricIndicn e(a a type cultivator, Milyangrows wa n) undeg24 r conditions describe commerciaTablA n di . eI l &f> granular formulation of BHC was sprayed at 40 kg/ha at the first and 30 kg/ha at the second generation time of rice stem borer. Harvested rice grains were dehusked to obtain a brown rice sample.
1: Field plots for BHC residue experiments
- ff Inlet
' Sj Ci Ai Bl Spraye: A first da t generation time of rice stem borer '&%%£:*&ix^«£i? *•*•?>>'#:'<.;-x. Bs Sprayed at second generation A* Bt C* tim ricf eo e stem borer '''$ Contro: C l without spray v:-2$:-Z&''£'-'ZZ:;''2: •;'-r'>/i?:'.^:<1
'?*• Bi c» A>
'>:•'<>;<&;•: •'-•''•'''•'''-''.,'-.:;£-» Outlet
TABL ; EFielI d condition paddr sfo y rice growth
Kyonggi area Honam area
Transplanting June 1 June 12
Pesticide application 1st generation tine Jun9 e1 Jun0 e2 of rice stem borer 2nd generation tine August 9 August 15 of rice stem borer
Harvesting Octobe0 r1 September 23
Soil type Sandy loam Silty loam 56 Polishin cookind gan g procedures;
Brown rice was polished with a laboratory mill, McGrill Miller No. 2 model polishine Th . second0 g14 tim d adjusteobtais o san t ewa 0 4 n o dt 100d an $ $ polishings70 , respectively.
Polished rice was washed 3 times with the same weight of distilled wate shakiny rb decantationd gan washed-drainee Ih . dbaseg ric0 de(5 on polishe ricew dra cookes )wa d wit time6 h1. s volum watef ea o n ri conventional aluminiuheate a automatin a n o r ro t mpo c electric rice cooker (indirect heating), allowe minute0 3 coo o dr t root lfo sa m temperature and subjecte residuo dt e analysis.
Gas ohromatographio analysis;
Extraction and clean-up of BHC residues in raw rice grains and rice bran were made according to a standard procedure (7)t using 20 g of powdered samples.
For extractio cookef no redistillef do ricel m 0 ,5 d wates rwa added to 50 g of sample (equivalent to 2O g of raw rice), blended for 2 minutes and subjected to the acetonitrile extraction-florisil column method (8).
Gas chromatographic determinatio mads nwa e using Varian Aerograph- model 2100-40 ohromatograph, stainlesm equippec O IS dsz witm steelm h6 , U-shaped column packed wit OV-1$ h5 7 (methyl phenyl silicone)/60-100 mesh Chromosor electrod an W A n, bW captur e detecto "TJi)r( standarA . d isomersC BH e - Th .£ d an f ) curv, constructes /i e wa , oC r dfo quantitation residue C limiBB f to tes n si t sample 0.00s swa 2 mg/kr gfo -isomer• t V 0.00 d , th fsan * 6le • -isomer mg/kth r gfo . Accordin- re a o gt cover yisomere teseacth f o f tdifferenhg o n si usinji 5 g0. t samplese ,th recoveries range reproducibilite dth 115 o d t fro #an 5 m7 satisfactorys ywa . Ho correction for percentage recovery was made.
14C-BHC experiments;
Paddy rice plants (an Indica type variety, Suwon 264) were trans- plante plastin Juni n do 2 e1 c Wagner pots lined with double layerf so polyethylene fil preveno mt t leakag waterf eo , under outdoor conditions. The pots were filled with paddy soil sandf so y loam take- n ex fro e mth perimental farm of this Institute and flooded in 2-cm depth throughout the growing period by frequent irrigation. Eighteen of these pots were submerged side by side in a rectangular pit (2.2 x 1.1 m) so that the
57 water surface of the pot was levelled with the surrounding water to simulate practical field conditions. Fertilizer pesticided san s were applied accordin conventionao gt l agricultural practices.
An exaggerated amount of « -(U- C)-BHC (250|tCi, purchased from Araersham Radiochemical Centre Ltd., UK; 50 rnCi/m mole in 5 ml toluene) was used for only one pot with 3 stumps of rice plants on August 25; the second generation time of the rice stem borer. The labelled material was mixed with 0.6 g of technical BHC powder and 5 g talc in a vessel made of aluminium foil. 20 g of soil was thoroughly mixed with the above mixture and spread evenly on the soil surface after decanting the irrigated water. The pots were flooded again in 2 cm depth.
Three pots were left without applicatio servo nt controls ea , and 14 pots received treatment with cold BHC under conditions similar 14 to those user C-BHCdfo .
The plants were harveste Octoben do 7 (cuabovm r2 c soie t7 eth l surface) planto Tw . s treated wit labellee hth d compound were taken autoradiographyr fo rese th t d serve,an collectior dfo grainse th f no .
Determination of C-activity;
Plant samples were digested and counted according to Mahin and Lofberfollowss a ) g(9 t Air-dried stra browd wan n rice were powdered mesht0 o5 sample g whicf ,o 1 h0. s were bottoe placeth countinf n mo do g vials and 0.2 ml of 60j£ perchloric acid was added to each vial. When the samples were thoroughly wetted, 0.4 ml of 30$ hydrogen peroxide was added viae Th .l caps were tightene warmed dhoursan 2 75°o r dt Cfo , with occasional agitation. After coolin rooo gt m temperaturef o l m ,6 solutioO PP PPO/g f o 6 Celloslov ( nl 1 m toluene0 1 d ean ) were added. The digested samples were 1 Liquicounte Alok60 n a C dn adLS i Scintillatio n Counter; counting efficiency 88.356.
RESULT DISCUSSIOND SAN S
BHC residue brown si n rice (field experiment);
BHC residue brown si n rice sample e showe Th s ar Tabl n ni . eII background level of BHC residues in brown rice was 2.3 times higher in Honam area than in Kyonggi area, which may reflect previous usage pattern of the pesticide. In the Honam area, higher BHC residues after the second application may be related to the interval between
58 applicatio day0 Honar 6 Kyongg d sfo d harvesd man an n an 0 i(4 t area s respectively). These results are similar to those obtained by Kanesawa (3).
The Japanese tolerance limibrowr totafo f to n2 G mg/k lric0. BH s gei seconane dth d applicatio paddo t C y BH ric f approachins no ei g that limit. For safe use patterns, it may be recommended to restrict BHC application, if possible, to the first generation time of the stem borer.
Partitionin residueC polishine BH th f g o n si g process;
BHC residues in polished rice products are shown in Table III. The partition ratio residuef so s into polished rice grai ricd nan e bran were 20:80 and 8:92 for 70$ and 100$ polishings respectively (Table IV). This patter similas foue nwa th r n isomersri . Since rice bran contains a higher amount of oil than polished rice grain, it is expected that polishin highea o gt r degree would resul morn residuetC i e BH th n si bran (Table IV). It is of interest to note that partitioning of the residues does not parallel partitioning of the oil. This would suggest the involvement of other factors such as "preferential binding" to specific components e.g. crude fibers.
The rice animabran a sourcl ns a oi l serve r n efeedo a n sa . About residueC BH 80-90e th s f $o presen brown ti n ric transferres ei e th o dt bran fraction, resulting in a residue level of 3 rag/kg in the bran and bran-derivee mg/k2 1 th o n gt i p u toxicologicae dlighe th oil th f to n . I l data of BHC, these results should be critically examined.
59 TABL : BHCEII * residue brown si n rice
Treatment Residue (me/k^) eC fr <£ 6 Total
Kyonggi area
Control without 0.003 TR TR TR 0.008 spray
Sprayet 1s t da generation time ricf o e stem "borer 0.008 0.011 0.002 TR 0.022
Sprayed 2n t da generation time of rice stem borer 0.041 0.008 0.007 TR 0.057
Honara area
Control without 0.008 0.004 0.003 0.003 0.018 spray
Sprayet 1s t da generation time of rice stem borer 0.008 0.008 0.002 0.004 0.022
Sprayed 2n t da generation time of rice stem borer 0.108 0.028 0.016 0.029 0.181
* Relative composition of technical BHC: «£- 68$, ft - 8$, If - 16$, Data are mean of three determinations tracT= R 0.002mg/kg, < e 4 (<* , ,^ 0.006< 6 mg/kg) (Half-value of the upper limit was used in calculating total and average values)
60 TABLE III; Partitioning of BHC residues in the polishing process
Residue (mg/kg) Sample r o« C a < Total Brown rice 0.165 0.019 0.030 0.086 0.300 7056 polishing Rice grain 0.032 0.004 0.005 0.012 0.053 Rice bran 1.770 0.207 0.3160.942 3.235
100$ polishing Rice grain 0.017 0.003 0.003 0.006 0.029 Rice bran 1.636 0.156 0.265 1.000 3.057
residuecontenC l BH Oi TABL d ; polishetan n sEi IV d rice products
Sample contenl Oi % t % Partitioning & Partitioning o: of oil BHC residues
Brown rice 3.0 100 100 l
100j£ polishing Rice grain 0.7 20 8 Rice bran 26.5 80 92
Effect of cooking on BHC residues;
The polished rice grain is usually subjected to washing and cooking procedures prior to human ingestion. The effects of such procedures residueC onBH showe sar Tabln ni . eRemovaV 60-70f lo totaf $o l residue by washing confirms previous findingsuggestd an Mokherje) y sb s(6 l a t ee the significance of washing before cooking in diminishing BHC residues. Cooking removed much less BHC residues.
61 In the light of these findings, it is maintained that polishing and washing processes played a major role in the elimination of most BHC residues present in brown rice. At the point of ingestion, BHC residues are probably less than 0.002 mg/kg.
TABLE V; Effects of washing and cooking on BHG residues
Treatment 70$ polished rice 1005S polished rice
BHC (mg/kg, remainin% g BHC (mg/kg % remaining based on residue basen do residue raw rice) raw rice) none 0.053 100 0.029 100 After washing 0.022. 40 0.009 31 After cooking with conventional kettle 0.014 26 0.008 28 After cooking with electric cooker 0.008 15 0.007 24
14,'C-BH ricn i G e plants
2.856 of the applied ^C-activity was recovered in the rice grain and straw graie Th .n contained totae 14.95th lf 6 o recovered activity. Work is in progress to characterize and/or identify the possible metabolite graie strawd th nan n si .
REFERENCES
] [1 CASIDA, J.K., ALLEKT, T.G., Agricultural Chemicals (19521 4 , J_ ,) [2] LICHTENSTEIN, E.P., J. Agr. Pood Chen. J_, 430 (1959)
[3] KANESAWA, S., Bull. Nat'1 Inst. Agric. Sci.t Ser. C. (Japan), 9 (19712J2.10 , ) [4] LISKA, B.J. Anim. ,J . Sci., 2J_ (19687 ,82 ) [5] TAKEDA, M., OTSUKX, K. SEIKTA, H., TANABE, H., OKAJIMA, S., SAKAI, Y. Shokuhin Eiseigafcu Zasshi (Japan), 14. (19732 ,14 ) [6] IfJKHERJEE, G., BANERJEE, T., MJKHERJEE, A., MATHEW, T.V., Res. Ind. (India), 18, 85 (1973) [7] JAPANESE SOC. ANAL. CHEM., KANTO BRANCH (ed.), Manual of Pollution Analysis Kyorits, , 1-b35 ,J_ . ,p u Pub. Co., Tokyo (1972) [8] MCMAHON, B.H. and SAWYER, L.C., (ed.), Pesticide Analytical Manual, lj Section 212. 13a, PooDrud dan g Admin. DeptS ,U . Health, Education and Welfare (1977) [9] MAHIN, D.T., LOFBERG, R.T., Anal. Biochem., l£, 500 (1966) 62 NEOASOZINE RESIDUE RICN SI E
Yong-Hwrd Su-Raan E M eLE aKI Environmental Chemistry Laboratory Korea Atomic Energy Research Institute Seoul| Korea
ABSTRACT
Residues of neoasozine in rice grain were determined by neutron activatio oolorimetrid nan c techniques. Twice applicatio chemicae th f no l before flowerin leat increaseo no t d d gdi d residue levels while 4-times application resulted in significant increase in the residue level (up mg/kg)5 0. neutroe - Th .4 to0. n activation techniqu advantageous ewa s because of its high sensitivity and the smaller sample amounts required for analysis partitioe Th . n rati arsenif o c residues into graid nan bra 73:2s nwa 100$,n ?i polished rice. residue brae Mosth th n f n to i e transferres wa oilcake th o dt e fraction,
IWTROPtJGTION
An organoarsenic fungicide, neoasozine (ferric ammonium salf o t methyl arsonate) is currently used for the control of sheath blight diseas paddn ei y ric Korean i eusags beeIt s .e ha n steadily increasing in recent years; reachin ton0 g 9 activ f so e ingredien 1978n ti e Du . to high toxicit neoasozinf o arsenico f yt o e d us le e ric n ,ei th s eha considerable concern. Substitute diemicalcontroe th r sheatf lo fo s h blight diseas paddn ei y ric antibiotie ear c fungicides suc polyoxis ha n and validamycin whic knowexpensivee e b h ar o nt . Report residuen so s of organoarsenic pesticides are limited (l) (2). This work was, therefore, undertaken to determine whether the conventional usage of neoasozine for rice would cause a residue problem.
MATERIALS AMP METHODS
Field experiments;
Paddy rice plantIndicn a f so a type cultivar, Milyan wer4 g2 e transplanted in an experimental paddy field divided into 9 plots (3 for p each treatment), 300 m each in Kyonggi area and managed according to
63 conventional agricultural practices. A commercial 6.5$ neoasozine preparatio sprayes kg/h3 nwa 1. at da twic e Augusd (Julan ) 2 11 ty2 or four times (July 21, August 4f August 11 and August 22). The
flowering period lasteweea r k fo dbeginnin gOctoben O Augus . t r4 15 t rice plantstumo3 1 f so s wer t froecu m each plod graintan s were collected, dehulle stored dan analysisr dfo .
Neutron^activation analysis of arsenic;
The metho dmodifiea use s dwa d versio previouslf no y described procedure ) (4) (3 sgrae .powderef On o m d rice sample packea n di polyethylene ampoul s irradiateewa pneumatia n di c transfer system TRTGe ofth A MarReactoI kII r neutroa 0 (2MW 1 t a x . ) n5 1. flu f xo 2 neutrons/c mminutes0 2 /sec r fo . . Afte cone f hourso 4 r2 l ."i HNO,5 . and 3 ml of cone. H-SO. were added to the irradiated sample. The mixtur warmes e wa coned dan . HNO., added unti solutioe lth n became clear. perchloril m 2 0. c solutioe aci s th adde dwa d s digestedan nwa d dan treated saturatewitl m h2 d ammonium oxalate solution mixture Th . e s transferre wa generatios ga a o dt conenl m bottl5 . d HG1l m ean ,2
15$ KL solution and 0.4 ml 35$ SnCl2 in cone. HC1 were added. After 15 minutes s addesandf o wa initiato g n dt y Z , 3 generations ega e .Th gacaptures swa d durin trahoua e n gon pri fille silvedf o witl m r h4 diethyldithiocarbamat pyridine)l m aliquotl e0 m (Ag-DDC20 o n Tw i . s g ;1 solutioe ofth n were counte Alokn a n adi model PC-IOE liquid scintillation counter, 72 hours after irradiation. A standard curve (Pig. l) was constructe irradiatiny b d samplg m 0 As-0,gf 1 eo .
0 0.05 0.10 0.15 0.20 0.25 Amount of As 0 (fig)
: Standar .g«1 . ddeterminatioe curvth r fo e n of As by nuclear activation technique
64 Colorimetric analysi arsenicf so ;
A standard procedur adoptes wa ) de(5 usin ricg 0 eg1 sampler sfo analysis standarA . d curv shows i e Fign ni .. 2
0.4
0.3
CM CM p 0.2 o
0.1
0 1 5 o Amount of As 0, (pg)
Rig; Standar2 . determinatiode curvth r efo n coloriraetriy b s A f o c method
RESULT DISCUSSIOD SAN N
Arsenic residue brown si n rice sample showe t ar sI Tabln ni . eI ma seee yb n that twice application before flowerin caust no y ed an gdi significant increas residue th n ei e leve browf lo n rice. However, 4-times application of the chemical until the time of flowering period resulted in a 4-5 fold increase of the residue level. Results obtained from both techniques were in good agreement. However, the neutron activation technique may have advantages over the colorimetric method because of its high sensitivity and the small sample quantities require analysisr dfo . Residues found after 4-times applicatiof no neoasozine may approach the lower tolerance limit. It is, therefore, suggeste restric o dt pattere chemicae us th e f tth n o twice-applicatio o lt n befor flowerine eth g time.
Partitionin arsenif go c residue cakd graine s an eth wa l n s,i oi studied after subjecting brown rio polishino et g wit laboratorha y mill to yield 100J& polished rioe and bran. The latter was further fractionated (n-hexane soxhlet extractio hours4 2 r n)fo inte oth cakeoi d resulte lan Th .showe s ar Tabl n ni . PolishineII d gle to 3-5 fold increase of As residue in the bran which was mostly retained by the oilcake, following hexane extraction. Although the products consumed directly by humans (grain and oil) contain residue levels lower tha tolerance nth e limit maintaines i t ,i d
65 that the higher arsenic concentrations found in the cake (which serves as animal feed) should be carefully examined in the light of toxicological data.
TABLE II; Arsenic residues in polished rioe, oil and oil cake
Sample % weight Control 4— times applicatiof no of fraction' nArtaR Brown rice 100 0.125 100 0.548 100 10056 polished rice 91.6 0.064 53 0.428 73 Rice bran 8.4 0.608 47 1.771 27 Oil 1.8 0.089 1 0.101 3 Oilcake 6.6 0.768 46 2.204 24 Dat meane a ar thre f so e determinations * neutron activation analysis TABL t EArseniI c residue "brown si n rice Treatment Res idues *( mg/kg) Activation Colorimetrio Control 0.104 i 0.030 ^0.10 2-times application 0.119 - 0.021 <0.10 4-tiraes application 0.411 - 0.012 0.566 i 0.028 Dat* meane aar standar s- d deviatio ninf no e determinations fro3 ( m each plot) 66 REFERENCES [l] WJBLE, R.L., HOLT, E.G., McBEE, G.G., J. Agr. FVsod Ghem., 17, 1247 (1969) [2] TOJIMDTO, Y., KAWAHARA, J., NAKAMJRA, H., Bull. Agr. Ghem. Inspect. Sta., 12_, 71 (1972) ] [3 KIMJRA , MORISHIMAY. , , KOGAH. , , HONDAT. , , KAWAIY. , , H. , KIMURA, K., MIYAGUGHI, Y., NISHIWAKI, Y., Radioiso-topes, l6_, 537 (1967) [4] LEB, C., KIM, N.B., and LEE, I.C., KAERI Technical Report, 2, No. 2 (1975) ] [5 HORWITZ . (Ed.)W , , Official Method f Analysiso s , Assoc. Off. Anal. Chemists, 12th Ed., p. 428, Washington D.G. (1975) 67 2. REPORT 2.1. ZNTROPtJGTiay Growing world population) industrializatio intensificatiod nan n of agricultura fisheried lan s practices have greatly increase neee dth d during recent decades to protect the resources concerned, and the qualit foof agriculturad yo dan l environment. Ihese trends have also resulted in a growing range of contaminants including pesticide residues and concer bees nha n expresse nationat da internationad lan l leveo lt protect man foo s environmend ,hi d an t from possible contaminatioy nb chemical residues. This programme is primarily concerned with the fate of pesticide residue edibln si e oil related san d products frotime applicatiomf th eo n of the chemical in the field or through processing to the instant of consumptio many nb . Thi particularls si y importan foor tfo d moving into international commerce. Activities under this programm closele ear y relate Join e thoso dth t tf eo PAO/HH O programm pesticidn eo e residues in food. The latter programme leads to the recommendation of pesticide residue tolerances on the basis of the best available agricultural, analytical, biochemical and toxicological data. Nuclear techniques greaf coulo e tdb assistanc existino et g monitoring programmes Joine Th .t PAO/IAEA programme, being scientifically and problem-oriented, could assis defininn ti g problem area respecn si t to pollutants. This would ensur morea e rationa efficiend lan t application of food monitoring facilities in the various countries. There was also no doubt about the value of isotope techniques in checking the reliability and accuracy of conventional methods, estimating recovery rates and in providing a unique tool e.g. in the quantitative determination of that residupara f to e which remains "bound resistd "an s extractioy nb solvents. Radioisotope techniques provid powerfuea l too tacklinn li g pesticide residue problems thin I .s context, some advantages are:- A - Radioassay provides an immediate and accurate measure of the total initial residue. B - Loss of total residue through harvest, storage, washing, milling, volatility, followe e etcb n .ca d quantitatively. C - Radioaesay of extracts provides evidence of extraction or recovery completenes possiblf o d san e chemical bindin residuesf go . 69 Radioassa- D suitablf yo y fractionated extracts provides rapid characterization of residues in terms of parent pesticide, polar and other metabolites. E - The fate of a labelled pesticide can be followed specifically in the presence of background levels of other pesticides including the one being studied. P - Experiments with labelled pesticides enable total balance sheets preparete ob termn di distributiof so n withi producte nth , loss by volatility, binding, etc. For developin recommendationss git meetine ,th g first reviewed and discusse papere dth section si . n1 2.2. MEETING OBJECTIVES 2.2*1 revieo T *progrese wth programme th f so e 2.2.2. To discuss problems related to methodology and labelled substrates 2.2.3 preparo T . publicatior efo scientifie nth c dat informatiod aan n obtained since the last report (IAEA-218 Technical Document Series, 1979) 2.2.4. To identify problems and priorities of related subject areas and to make appropriate recommendations. SOM2.3. .E HIGHLIGHTS 2.3.1. Pesticide food san d Under this programme fate magnitudd ,th e an pesticidf eo e residues were studie : cottondin , maize, groundnut, olive, rice, rapeseed, sesame, soybean, coco daird aan y animals, using seventeen radiolabelle nond dan - labelled pesticide chemicals. These were: Hexachlorocyclohexane, carbaryl, leptophos, cyolane, dursban, monocrotophos, dimethoate, propoxur, chlor- fenvinphos, DDT, endrin, dieldrin, heptachlor, nitrofen, alachlor, butachlor and neoasozine. 2.3.2 processinl Oi . g An important featur emerges eha d from studie fate th f e o f so pesticide residues through processin oilf go . Commercial processing procedures usually include alkali treatment, bleaching and deodorization (or winterization at low temperatures). The alkali treatment is effective in "removing" organophosphat oarbamatd ean e residue whill soi froee mth deodorization (involving steam-distillation efficiens )i removinn ti g residue halogenatef so d hydrocarbon procesBBCe d s Th an .lik T f so eDD 70 winterization proved to be least effective in reducing organophosphate residues present in oil. 2.3.3. Garbaryl Various investigation carbaryn so l residue cornn si , cotton seed product daird san y products indicate that applicatio chemicale th f no , under good agricultural practice condition unlikels si preseno yt y tan hazard to the consumer. ricn 2.3.4i eC productBH . s Concern has been expressed "by the meeting's participants in relatio exceptionalle th o nt y hig residueS hBB ppm3 s( ) foun ricn di e livestoco brat Korean d ni brafe e s th .kn i f wito Abou $ h t80 possibl e appearanc residuef eo mil n sdairi d kan y product levelt sa s exceeding the "maximum residue limit". E.g., MRL for ¥ -BBS is 0.01 mg/kg in whole milk (Pesticide Residue Poodn si , PAO, 1978, Serie 10). s.No 3. KBSOMHafDATIONS In the light of the original objectives and earlier recommendations, the meeting noted with satisfaction thaprogramme tth achieves eha s dit goals. In addition, the following recommendations were addressed to the Joint FAO/IAEA Secretaria ensuro t e essential continuit mose th t d yan effective contribution of related research programmes to the growing problem contaminantf so s enterin agriculturae gth food dan l environment: encourago T 3.1 .developmen e eth applicatiod tan promisinf no g isotope techniques in the environmental context. exploro T 3.2.e way meand san establiso st h better isotope tracer facilitie appropriatt sa e centres, especiall developinn yi g Member Statesstude th pesticidf yo r ,fo e residue problems under local conditions. exploro T 3.3.e way meand san improvinf so supple gth y and/or availabilit isotopically-labellef yo d compound vitaa s sa l aid to research collaborators. provido T 3.4.e trainin nucleaf o e g us r course e techniqueth n so s for studying food and agricultural environment pollution problems at suitable regional centres with particular reference to the problem needd san developinf so g countries. 71 3.5« To facilitate tracer-aided studies of the fate and significance terrestriae inth aquatid lan c environmen certaif to n persistent and apparently already widely dispersed contaminants such as DDT, hexachlorobenzene and polychlorinated biphenyls. exteno T 3.6.d tracer-aided studie naturee th f so , magnitudd ean significanc "unextractablef eo "houndr "o " pesticide residues in soil| plants and food. initiateo T 3.7* funds ,a s become available, coordinated studief so depositio disappearancd nan pesticidf eo e residue dairn si y products. 3.8. To initiate, as funds become available, a coordinated research programm studief eo behaviouf so pesticidf ro e chemicale th n si aquatic and marine environment, with particular emphasis on bioaccumulation in fishery products. initiateo T 3.9* funds ,a s become available ,coordinatea d attacn ko pesticide residue problem storen si d grains. 4. CONCLUSIONS 4.1. There was abundant evidence of chemical residue problems in developing countries affecting foo potentiaf do l economir co health importance. These problems were often relatively neglected. Through this programme, exceptionally high levels of leptophos residue miln si k were reported. 4.2. Many of the problems were of continuing nature. While this programme had provided answers to specific questions new ones continued to arise. For example, the introduction of alternative pesticides such as cyolane and dursban for control of cotton pests in Egyp replaco t potentialle eth y hazardous leptophos. 4.3. The meeting felt that the provision of training courses for suitable graduate developinf so g member state facilitato st e the exploitation of stable and radioactive isotope tracer technique identificatioe th n si studd n an thei f yo n row problems under thei conditionn row s should continuo et have high priority. 4.4. Notin implementatioe gth morf no e "problem-oriented" coordinated research programmes meetine ,th g felt abl identifo et y further problem areas requiring coordinated attack by isotopic tracer- aided studies: - a. Origins, fate and significance of undesirable chemical residue plant-soil-waten si r syst<»ms with particular referenc non-agriculturao et l sources, e.g industrian .i l effluent. 72 b. Behaviour of toxic residues in estuarine and inland fisheries with particular attentio magnitudee th o nt , behaviour and significance of industrial residues. c. Bioooncentration of chemical residues in fishery products. This is of particular importance because of the continuing intensification of agriculture and reliance upon pesticides. 4.5» Data generated under this programme is likely to be of significant value not only to the various countries involved, but also to the Joint PAD/WHO pesticide residue programme which sets international recommendations for maximum residue limits (MRL) and acceptable daily intake (ADl). 4.6. The close contact established between the PAO/IAEA Secretariat and research workers in different countries through the Agency's research contract programme represents a significant contribution to country development, i.e. to assist scientists to identify and study their own problems under their local conditions, to use nuclear and related techniques effectively and to maintain the closest possible contact with their counterparts of the more advanced countries. 73 LIST OF PARTICIPANTS Dr. M.M. AHMED Agricultural Research Corporation Entomology Section Wad Medani Sudan CZAPLICK. E . Dr E Plant Protection Institute Grunwaldzka 189 Poznan Poland S.R. E Dr .LE Environmental Chemistry Laboratory Korea Atomic Energy Research Institute P.O.Bo Cheon» x7 g Ryang Seoul Korea P.E. Dr . PABLO University of the Philippines Natural Science Research Centre Diliman, Quezon City 3004 Philippines M.J. Dr . QURESHI Nuclear Institute for Agriculture and Biology P.O.Box 128 Paisalabad Pakistan RAGH. K . UDr Bhabha Atomic Research Centre Biology and Agriculture Division Mod. Labs. Trombay5 , 08 Bomba 0 40 y India Dr. S.M.A.D. ZAYED Pesticide Toxicology Laboratory Middle Eastern Regional Radioisotope Centre Dokfci, Cairo Arab Republic of Egypt OBSERVERS Dr. G. ZWERENZ Osterreichische Unilever Ges.m.b.H. Breitenfurterstrasse 239 A-1230 Vienna Austria Dipl. Ing WOMASTE. .R K Bundesanstalt fttr Pflanzenschutz Trunnerstrasse5 A-1020 Vienna Austria SECRETARIAT Dr. A. HASSAN IAEA (Scientific Secretary) Wagraraerstrasse 5 P.O.Bo0 x10 A-1400 Vienna Austria 75