T-254 SEN-I GAKKAISHI ( •ñ•¶) (122)

(Received July 24, 1983)

PRACTICAL APPLICATION OF EMPENTHRIN

AS A MOTHPROOFER OF TEXTILE

By Kiyofumi Yoshida, Shigenori Tsuda and Yoshitoshi Okuno

(Pesticides Research Laboratory, Takarazuka Research Center, Sumitomo Chemical Co., Ltd. 4-2-1, Takatsukasa, Takarazuka, Hyogo 665, Japan)

Abstract

Studies on biological activity of d-empenthrin against textile pests were performed. d-Em-

penthrin was found to have sufficient efficacy against casemaking clothes moth and black carpet beetle as a volatile insecticide at room temperature under closed conditions. A d-empenthrin

mothproofer strip which contained 0.5 gram of d-empenthrin on a 150 cm' (10•~15 cm) filter paper

could control textile pests in a wardrobe for more than 6 months. It was also indicated that small

pieces (for example, 3•~ 10 cm, 3•~ 3 cm) of d-empenthrin mothproofer strip could control even in the chest of a drawer packed with clothes.

Since the chemical structures of the insecticidal INTRODUCTION components of pyrethrum extracts were elucidated It is reported that there are more than 30 kinds by Staudinger et al. (1924)9), many synthetic of pests which damage textile.1) Among them, pyrethroids such as allethrin10), tetramethrin"7, case-making clothes moth, Tinea pellionella, web- resmethrin12), phenothrin13), and permethrin'4) bing clothes moth, Tineola bisselliella, black carpet have been synthesized and widely used as insecti- beetle, Attagenus piceus and varied carpet beetle, cides for household and public health purposes. Anthrenus verbasci are the most harmful pests.1) These synthetic pyrethroids have attracted atten- Control methods against these pests are generally tion for textile pests control because they have the classified into two ways.2) One is treatment of advantage of high insecticidal activity with low clothes with mothproofing chemicals. Since di- mammalian toxicity.15)16)17) eldrin was discovered in the late 1950s, it had been Recently, Kitamura et al.") introduced a new used as a wool protectant.3) However the use synthetic pyrethroid, d-empenthrin (coded as of dieldrin for mothproofing treatment is now S-2852 Forte or Vaporthrin® for its registered prohibited in most countries because of its per- trade name for Sumitomo Chemical Co., Ltd.), sistence in the environment and extremely high which has a higher vapor pressure in comparison toxicity to mammals.') Today, Eulan, Mitin, etc , with conventional pyrethroids. This paper de- are commonly used for this purpose instead of scribes the characteristics of d-empenthrin based dieldrin.2)5) on several studies about biological activity against The other is the use of vapor action of chemicals textile pests. Performance of the practical formu- having volatile property, such as naphthalene, lations and the application methods are also p-dichlorobenzene, dichlorvos and lindane.6) How- discussed. ever, each of these chemicals has its own disad- vantages.7)8)Therefore, it is necessaryto find an insecticide which has a high vapor pressure, a high insecticidal activity and a low mammalian toxicity . However none of the insecticides invented seemed so far to meet these requirements as can be chemicalstructureofd-empenthrin utilized for the vaporific mothproofer. (123) Vol. 40, No. 7 (1984) T-255

EXPERIMENTAL

I. Chemicals

d-empenthrin; (RS)-1-ethynyl-2-methylpent-2-

enyl (1R) cis, trans-chrysanthemate, purity

93.5%, Vaporthrin® (Code No. S-2852 Forte),

Sumitomo Chemical Co., Ltd.

d-allethrin; (RS) -3-allyl-2-methyl-4-oxocyclo

pent-2-enyl (1R) cis, trans-chrysanthemate,

purity 91.3%, Pynamin® -Forte, Sumitomo Chemical Co., Ltd.

dichlorvos; 2,2-dichlorovinyl 0,0-dimethylphos

phate, purity 91.9%, Kureha Chemical lindane; r-1,2,3,4,5,6-hexachlorobenzene, Tech

nical grade, Nippon Soda Fig. 1. Test container for evaluating vaporific activity of insecticides para-dichlorobenzene; 1,4-dichlorobenzene, ex A; Insecticide impregnated paper trapure reagent, Wako Pure Chemical Indus (2•~2cm) tries Ltd. B; A piece of wool muslin (2•~2 cm) II. Insects C : Test insects Case-making clothes moth, Tinea pellionella was

reared on dried fish-based diet.") The larvae used dish (8.5cm in diameter). After drying, twenty

were 40 to 50 days old after egg deposition, the eggs and 20 larvae of case-making clothes moth

adults, 3 to 5 days old after emergence, and the were kept on the wool muslin for 10 days and 2

eggs, 3 to 4 days old after oviposition. Black carpet days, respectively. Insecticidal activity against eggs

beetle, Attagenus piceus was reared on the same was evaluated by counting the mortality of hatched

diet and the larvae used were 6 to 12 months old. first-instar larvae and the inhibition rate of egg

Ill. Test methods hatching.20 Insecticidal activity against larvae was

1) Topical application method evaluated by counting mortality of larvae.

A 0.3ul of acetone solutions of the test chemical 4) Simulated test method (1)

at various concentrations was topically applied to Four sheets of cotton cloth (35•~35 cm) were

dorsum prothorax of case-making clothes moth hung from the ceiling of a box (made of wood,

adults. 35•~35•~70cm). Twenty larvae of test insects with

2) Evaluation method for vaporific activity of

insecticide

Insects were put on the bottom of a petri dish

(8.8 cm in diameter, 5.8 cm in height) together with a piece of wool muslin (ca. 40 mg/2•~2 cm),

and covered with the dish. Between the dishes, a

wire net (35 mesh) was set in order to prevent

insects from coming into direct contact with the

insecticide. A sheet of insecticide-impregnated

filter paper (2•~2 cm) was settled on the wire net

and the insects were exposed to the vapor of the

insecticide for 7 or 8 days (Fig. 1), and mortality of the insects was evaluated . Fig. 2. Simulated test method (1) 3) Contact toxicity test method A; Wood box (35•~35•~70 cm) A piece of pure wool muslin, on which acetone B; Cotton cloth (35•~35cm) solutions (1 ml) of various concentrations of the C; Insecticide test chemical were applied , was placed on a petri D; Wire net cage T-256 SEN-I GAKKAISHI (PVC) (124)

a piece of wool muslin (2•~2 cm) were set in a cage of each suit (Figure 3). Also, 20 eggs on the wool

muslin in a petri dish (8.5 cm in diameter) were (6 cm in diameter), made of 35 mesh stainless steel net, and the cage was also hung between cotton settled in 4 positions on the walls of the wardrobe. interceptions as shown in figure 2. Then, a sheet The mortalities of the adults, eggs and larvae were of filter paper impregnated with d-empenthrin observed after 24 hours, 10 days and 2 weeks. In addition, several pieces of wool muslin (10•~10 (3 grams of d-empenthrin on 3000 cm filter cm) were attached to each suit in order to analyse paper), or 8 tablets of 3 grams of p-dichlorobenzene was hung from the center of the ceiling. After 7 the quantity of d-empenthrin adsorbed on it. The

days exposure under the above condition, mortality same test were conducted for indicated period for

of the test insects and damage of the wool muslin 6 months after hanging of the insecticide was

were measured in the following procedure; initiated.

6) Simulated test method (3)

Test formulations were as follows:

d-Empenthrin mothproofing strip; 20 pieces of

This test was made at indicated intervals for 6 17 mg of d-empenthrin on 9 cm2 (3•~3 cm) filter

months after impregnation of the insecticide. paper, 6 pieces of 100 mg of d-empenthrin on

5) Simulated test method (2) 30 cm2 (3•~10 cm) filter paper, and 16 pieces of 3 grams of para-dichlorobenzene tablets (Commer Test formulations were as follows: cial product sold in Japan). d-Empenthrin mothproofing strip containing 0.5 Six woolen wears were laid in two rows (three gram of d-empenthrin on 150 cm2 (10•~15 cm) filter paper, 120 grams of p-dichlorobenzene ball layers in one row) in the chest of drawers (40x 84x 14 cm in size, 0.048 m3 in volume). Wire cages (Commercial product sold in Japan), 5 grams of 18.6% w/w dichlorvos strip (Commercial product containing ten larvae of case-making clothes moth

sold in Australia) and 0.176 m2 of 10% w/w lindane with a piece of wool muslin (2•~2 cm) were set on the surface of woolen wears, between them and paper (Commercial product sold in West Germany). Seven suits of clothes and test mothproofing underneath them at the bottom, and indicated

product were hung in a wardrobe (90•~180•~44cm, pieces of the test sample were placed uniformly at 0.713 m3 in volume). Wire cages containing 10 various spots in the chest of drawers. Mortality

insects, adults or larvae with a wool muslin, were of test insects was observed 2 weeks after the above

also hung up outside (2 cages) and inside (1 cage) conditions had been settled. Such tests were made

at indicated intervals for 8 weeks after the insecti-

cide application was made.

All the experiments were conducted at 26_??_1•Ž

and 60_??_10% in relative humidity.

7) Panel test for measuring the evaporation rate

of d-empenthrin from the mothproofer strip

Panel tests were conducted from autumn to

winter (7 panels, for 3 months during September

to November of 1982) and from spring to summer

(8 panels, for 3 months during April to June of 1983).

After the mothproofer strip was stopped to

hang in the wardrobe, the rest amount of d-

empenthrin on the mothproofer strip was analysed

by the method of Tsuda et al.") Then the Fig. 3. Simulated test method (2) A; Wardrobe (0.7 m3 in volume) evaporated amount or the evaporation rate of B; Insecticide d-empenthrin from it was calculated. C; Petri dish containing eggs The wardrobe was opened 3.2 times per day and

D; Suit hanging insect cages the volume were 0.9 m3 on the average in autumn (125) Vol. 40, No.7 (1984) T-257

utilized for volatile insecticide formulation test. That was opened 3.2 times per day and the . volume was 1.0 m3 on the average in spring test. 2. Basic insecticidal activity against a case- making clothes moth RESULTS AND DISCUSSION Basic insecticidal activity of d-empenthrin under

1. Physical and chemical properties open space condition was evaluated against each

Physical and chemical properties of d-empen- developmental stage of case-making clothes moth . thrin have been reported by Tsuda et al.21) The Table 2, Table 3 and Table 4 show the activities evaporation rate of d-empenthrin at 25•Ž was of several insecticides including d-empenthrin around 3 mg per day from a pulp-made sheet against larvae, eggs and adults of the moth. d-Empenthrin did not show high activity against (10•~10 cm, 0.3 mm in thickness).21) d-Empen- thrin is characterized as its higher vapor pressure; household insects as reported,") while it has i.e. the vapor pressure is almost ten times higher better efficacy against all developmental stages of than that of d-allethrin which has rather high case-making clothes moth. vapor pressure among conventional synthetic Table 5 shows the insecticidal activity of d- empenthrin by its vapor action against a case- pyrethroids.22> Table 1 shows vapor pressure of four insecticides, among which dichlorvos and making clothes moth and a black carpet beetle.

lindane have been used as vaporific insecticides The vapor of d-empenthrin showed higher insecti-

for textile pests at room temperature. Therefore, cidal activity against these textile pests than those

the result indicates that d-empenthrin will be of d-allethrin, lindane and p-dichlorobenzene. This indicates that d-empenthrin has a potential

Table 1. Vapor pressure of the insecticides to be used for textile pests control as a vaporific tested insecticide under closed conditions.

Table 2. Contact toxicity of d-empenthrin against case-making clothes moth, Tinea pel lionella, larvae

Table 3. Contact toxicity of d-empenthrin against case-making clothes moth, Tinea pellionella, eggs Exposure: 10 days T-258 SEN-I GAKKAISHI (•ñ•¶) (126)

Table 4. Insecticidal efficacy of d-empenthrin p-Dichlorobenzene showed very low effectiveness against case-making clothes moth, in both of the properties.

Tinea Pellionella, adults by topical Since it is supposed that the insects invade a application. wardrobe at the adult stage, the control of adults

and eggs of textile insects are primarily important

though only larvae make damage on textile.

Therefore, the efficacy of d-empenthrin moth-

proofer strip which contains 500 mg of d-empen- thrin on 150 cm2 (10•~15 cm) filter paper was

evaluated against adults and eggs of case-making

clothes moth under practical conditions. Table 7

3. Insecticidal efficacy of d-empenthrin in shows the result of the efficacy of d-empenthrin practical formulation and application mothproofer strip against adults and eggs of the Several trials were carried out for d-empenthrin moth in comparison with some conventional to evaluate its availability as a mothproofer. vaporific products. Table 6 shows the efficacy of d-empenthrin- The use of 2 sheets of d-empenthrin moth- impregnated paper against case-making clothes proofer strip showed good efficacy against adults moth and black carpet beetle in comparison with and eggs of the moth for 6 months. Although that of p-dichlorobenzene. It is found that d- 500 mg of d-empenthrin on 150 cm2 filter paper empenthrin impregnated paper is effective against has been expected to keep evaporating for around larval stage of case-making clothes moth for a long 3 or 4 months in an open space as reported,2t) term under closed conditions. Though the killing the efficacy of the strip under closed conditions efficacy of d-empenthrin against black carpet like in a wardrobe persist longer than that of beetle was not satisfactory, the feeding damage on expected. wool muslin was almost completely suppressed.

Table 5. Vapor action of several insecticides impregnated paper against case-making clothes moth and black carpet beetle Test insect: Case-making clothes moth, Tinea pellionella, larvae Black carpet beetle, Attagenus piceus, larvae Exposure : One week in 700 ml of glass dish (127) Vol. 40, No.7 (1984) T-259

Table 6. Biological efficacy of d-empenthrin and p-dichlorobenzene against textile pests by simulated test method (1) Test insect: Case-making clothes moth, Tinea pelltonella, larvae Black carpet beetle, Attagenus piceus, larvae

Table 7. Efficacy of d-empenthrin mothproofer strip and some commercial products against case-making clothes moth in 0.7 m3 wardrobe by simulated test method (2) Test insect: Case-making clothes moth, Tinea pellionella, adults and eggs

*1) O utside or inside of the suit, *2) % Mortality *3) % Inhibition of egg hatching + % mortality of hatched larvae *4) A mothproofer strip: 0.5 g of d-empenthrin/150 cm2 filter paper

Next, the test on mature larvae (40-50 days moth for 6 months. old) of the moth was also conducted (Table 8). The amount of d-empenthrin adsorbed on the Theseresults (Tab. 8) show that 4 or 7 sheets of cloth in the wardrobe was analysed in order to d-empenthrinmothproofer strip in a wardrobe know the relation between its amount and efficacy are consideredsufficient to control larvae of the against larvae. As shown in Figure 4, around 200 T-260 SEN-I GAKKAISHI (報 文) (128)

Table 8. Efficacy of d-empenthrin mothproofer strip against case-making clothes moth in 0.7 m3 wardrobe by simulated test method (2) Test insect: Case-making clothes moth, Tinea pellionella, larvae A mothproofer strip; 0.5 g of d-empenthrin/150 cm2 filter paper

*1)Outside or inside of the suit

average during April to June of 1983 (namely

2.4 mg per day). From these panel tests, it was

concluded that the evaporation would be con-

tinued for more than 6 months under practical

conditions like in a wardrobe.

In addition to the textile pests control in a

wardrobe, the control in a chest of drawers is also

important. The control in the chest of drawers is

assumed to be more difficult than that in the

wardrobe because the clothes are more densely

packed in the former case. Therefore, small pieces of d-empenthrin mothproofer strip were used for

Fig.4.Relationship between the amount of d the test in the chest of drawers. Table 9 shows

empenthrin adsorbed on a wool (100cm2) the performance of d-empenthrin mothproofer and mortality(%) or feeding (%) of case strips of 20 pieces (3•~3 cm) and 6 pieces (3•~10 makaing clothes moth, larvae in 0.7m3 cm) compared with that of 16 pieces of p-dichloro- wazdrobe. _??_;% Mortality,_?? ;% Feeding benzene tablet (3 grams of each tablet). These results suggest that some formulation like small

ƒÊg of d-empenthrin per 100 cm2 of cloth is enough pieces of d-empenthrin mothproofer strip will also to kill the larvae of the moth, and the effective enable d-empenthrin to be used for textile pests level of d-empenthrin for inhibition of the larval control even in a chest of drawers packed with feeding is around 150,ag per 100 cm2. numerous clothes.

As shown in Table 7, the efficacy of the moth- CONCLUSION proofer strip lasted for 6 months. In order to check the practically effective period for d-empen- 1) d-Empenthrin is effective against textile thrin to evaporate from the mothproofer strip, pests like case-making clothes moth, Tinea pel- lionella and black carpet beetle, Attagenus piceus panel tests were conducted from autumn to winter and from spring to summer. The results from as a volatile insecticide. these tests showed that the evaporation rate of 2) In practical use, 2 sheets of d-empenthrin d-empenthrin from the mothproofer strip was mothproofer strip containing 500 mg of d-empen-

143 mg per 3 months at 20.6•Ž in average during thrin on 150 cm2 filter paper are considered

September to November of 1982 (namely 1.6 mg enough to control adults and eggs of case-making per day) and 213 mg per 3 months at 22.3•Ž in clothes moth in the wardrobe for 6 months. (129) Vol. 40, No.7 (1984) T-261

Table 9. Efficacy of d-empenthrin mothproofer strip and p-dichlorobenzene against case-making clothes moth in 0.048 m3 of the chest of drawers by simulated test method (3)

*1) 1: Surface of wears, 2: Between wears, 3: Underneath wears Ave.: Average % of mortality of 1+2+3 Each result shows % mortality of insects '2) 17 mg of d-empenthrinl3x3 cm filter paper '3) 100 mg of d-empenthrin/3•~10 cm filter paper

3) Approximately 200ƒÊg of d-empenthrin ad- 5) R. J. Mayfield; Textile Progress, 11 (4), 1 sorbed on the cloth (100 cm2) in the wardrobe (1982) 6) T. Uchida and T. Harukawa; Botyu-Kagaku, totally kill the larvae of the insect whose stage is 7, 16 (1947) assumed to be most resistant to insecticides, and 7) W. S. Abbott and S. C. Billing; J. Econ. around 150ƒÊg of d-empenthrin per 100 cm2 show Entmol., 28, 493 (1935) complete inhibition of the larval feeding. 8) T. Matsuo, T. Nishioka, M. Hirano, Y. Suzuki,

4) The results of panel tests in wardrobes K. Tsushima, N. Itaya and H. Yoshioka; under practical conditions suggest that the evapo- Pestic. Sci., 11, 202 (1980) 9) H. Staudinger and L. Ruzicka; Helv. Chim. ration of d-empenthrin from the mothproofer strip Acta., 7, 117 (1924) is continued for more than 6 months. 10) M, S. Schechter, N. Green and F. B. LaForge; 5) In a chest of drawers, scattering of small J, Am. Chem. Soc., 71, 3165 (1949) pieces of the mothproofer strip containing d- 11) T. Kato, K. Ueda and K. Fujimoto; Agric. empenthrin (3x3 cm, 3x10 cm) is more effective Biol. Chem., 28, 914 (1964) for textile pests control than p-dichlorobenzene 12) M. Elliot, A. W. Farnham and N. F. Janes; tablets. Nature, 213, 493 (1967) 13) N. Itaya, K. Kamoshita, T. Mizutani, S. Kita

ACKNOWLEDGEMENT mura, S. Nakai, N. Kameda, K. Fujimoto and Y. Okuno; United State Patent, 3666789 The authors thank Dr. Yasuko Tsujii, Prof. of (1971) Nara Women's University, for the supply of the 14) M. Elliot, N. F. Janes and D. A. Pulman; colonies of textile pests used in this study and for British Patent, 024809, 024810 (1972) her advice on the biological evaluations. They 15) P. A. Duffield; Pestic. Sc4, 8, 279 (1977) express their thanks to Miss F. Yaku and Miss H. 16) R. E. Bry, R. A. Simonaitis, R. E. Boatright and 1. H. Lang; Soap and Chemical Special Higashino for their skillful technical assistance. ties, Blue Book, 35, 59 (1980) They are also grateful to Sumitomo Chemical Co., 17) R. E. Bry, R. E. Boatright, J. H. Lang and Ltd. for its permission to publish this work. R. A. Simonaitis; Soap and Chemical Special ties, Blue Book, 40 (1981) 18) S. Kitarnura, N. Itaya, Y. Okuno, N. Oono, M. Hirano, T. Matsuo, T. Mizutani and H. REFERENCES Takeda, Japan Patent 55-42045 (1980) 1) Y. Yamada; Botyu-Kagaku, 1, 9 (1937) 19) Y. Tsujii and K. Izumi; Botyu-Kagaku, 41, 2) Y. Tsujii; Botyu-Kagaku, 40 (4), 138 (1975) 36 (1976) 3) M. Lipson and J. R. McPhee; Text. Res. J., 20) R. E. Bry, R. E. Boatright and J. H. Lang; 28, 769 (1958) J. Econ. Entomol., 73, 449 (1980) 4) R. Nahta; Text. Chem. Col., 8, 279 (1973) 21) S. Tsuda, K. Yoshida and Y. Okuno; Soap T-262 SEN-I GAKKAISHI (報 文) (130)

and Chemical Specialties, "Empenthrin for 22) Y. Nishizawa; Bull. World Health Org., 44, fabric pest control", in press 325 (1971)

エンペンスリンの衣料防虫剤 としての実用効果

住友化学工業株式会社 吉田清 文,津 田重典,奥 野吉俊

新 規ピ レ スロ イ ドで あ る エ ン ペ ン スリ ン は,蒸 気圧 が タ ン ス 用 製 荊 と して 開 発 した,エ ンペ ン スリ ン防 虫紙 高く,常温 蒸 散 に よ る 衣 料 防 虫 剤 へ の 適 用 が 示 唆 さ れ る (150cm2汐 紙 に500mgの エ ン ペ ン ス リン含 有)は,実 用 。そ こ で,エ ン ペ ン ス リ ンの 衣 料 害 虫 に 対 す る 基 礎 効 力 を 的 に,タ ン ス あ た り2枚 施 用 す る こ と に よ り,6ケ 月 検 討 し た と こ ろ,イ ガ,ヒ メ カ ッ オブ シ ム シ に 対 し て 良 間イガ に 対 す る 効 果 が 期 待 で き る。エ ンペ ン ス リ ンは,製 好 な 効 力 を示 し,とり わけ,閉 鎖 系 で の 蒸 散 に よ る殺 虫 剤 的 な 工 夫に よ り,タ ン ス 馬 防 虫 鋼 と して ば か りでな く､ 効 力 は,卓 効 を 示 し た 。 撰 出 し用 防 虫剤 と して も,そ の 蘭 発 が 期 待 で き る。