SECOND CARNEGIE INQUIRY INTO POVERTY

AND DEVELOPMENT IN SOUTHERN AFRICA

Lead Toxicity and poverty: Pre­ liminary case study investigations in school children by

Yasmin von Schirrrling

Carnegie Conference Paper No. 180

Cape Town 13 - 19 April 1984 ISBN 0 7992 0701 2 There is a long history of human exposure to lead (1). Lead has been used since antiquity and its health effects were recognized before the Christian era (1,2,3.4). It is largely as a consequence of industrialised commodity production, however, that exposure to lead has intensified. Amongst adults, exposure is greatest for those who come into closest contact with the pro­ duction process, but for children exposure is more usually the result Of the interaction of several environmental and social risk factors.

The toxic nature of lead was well documented by the 2nd century B.C. and there is a history of public exposure to lead from food and drink (1). Lead poisoning was common in Roman times due to the wide use of lead in lining water pipes, earthenware containers and in storing wine (1,2). It became common among industrial workers during the 19th and early 20th centuries (5) when workers were exposed to lead in numerous occupations such as painting, plumbing, printing and many others. They were assumed to absorb lead in three ways - from contamination of food eaten at the workplace, by inhalation of fine lead dust and by absorption through the skin.

OCCUPATIONAL LEAD EXPOSURE Today, workers are exposed to lead in over one hundred occupations, including motor-vehicle assembly, panel-beating, battery manufacture and recovery, soldering, lead smelting, lead alloy production and in the glass, plastics, ceramics and paint industries. In most highly industrialised countries, stricter controls and improvements in industrial methods have helped ensure that occupational lead poisoning is no longer as prevalent as before (6). In South Africa however, in many work environments lead poisoning still occurs (7).

Lead is one of the ten most important metals in South African industry. It is used in some 2 000 factories, mines and works employing over 159 000 workers of whom about 14 500 work directly in contact with the metal (8) (see table 1). It was estimated by the 1975 Erasmus Commission of Enquiry on Occupational· Health (8) that if South Africa were to be examined by Swedish standards, 45,6% of the workers would have to.be withdrawn. The Commission reported that "Exposure (to lead) in the Republic is so inordinantly high that if the (lead using) factories where the investigations were carried out had been located in the U.S. or Sweden, they would have had to close." They reported that an investigation of sixty lead-handling factories had revealed S·:')urCE : Rsport cr, thE =:r.?.S"r;~uf Cm:'hli ssion of E'lc;uiry

Or! Occu~,.::n: iC:1al H~al 't.!-. I J 97c .

No cf NC. cf

.E:X~:. .'::.E~ 'v.'C ~-'.: c "!--::

-' - j -, -, 8'; - ?!"'::"'::(':.:ns: v·;orJ.:~ ~4 2 7 J·~·:'::'~=E:!:.ting "BE Paint manufacturE lO~ - E,8E:: Exp~EiveE & fi~ew0rkE 5 ! , Match man~fac~ur~ c ; - hgricul~u~al re~I~~Y :-.ie..::;·cf .:.c~':..!r~ , -, c " l: 2.:; ;:·ct-:::E.r~¥·, ~c.rd_ -:.a~y v,'cre one t.::'~es f. Oe'l Glas£ mc.nu~ac't.ur€ j 9e­ lL 240 :'.E:ac smf:lting E 762, CablE: rr.anufacture 14E 19 343 Ga!vanizing works 14 842 BattE~y ~c.nufac~ure 3J Cc.;·1)e!:" E:Llloy£

2 08E 2

that thirty-six percent of their workers had varying degrees of lead poison­ ing.

Whilst many firms have since tightened up on safety controls, there are many industries in South Africa where-workers are still at risk. The National Centre for Occupational Health stated in their 1980 annual report that "From the surveys carried out by the Centre and from the specimens received­ for analysis from some of these industries, there is definate evidence that lead absorption in South Africa is higher than is acceptable in the majority of other countries around the world (8).

Exposure to lead is covered by three general laws - the Factories Act, which makes provision for factory inspectors, the Health Act, which makes- lead poisoning notifiable to the Medical Officer of Health and the Workman's Com­ pensation Act, which makes provision for compensation to be paid to workers with lead poisoning (9). Although lead-poisoning is a notifiable illness in South Africa, between 1974 and 1983, there were only 76 official noti­ fications of lead poisoning in South Africa (10). Only extreme cases of lead poisoning-are notifiable by law, and there are no standards for occupational lead exposure_

CHILDHOOD LEAD EXPOSURE (An Overview) Lead poisoning among children was first reported in Australia in 1892 (11). In 1924 several cases of lead poisoning were reported in the USA, and it was proposed that pica, a perverted appetite for non-food items such as paint, was an important etiologic factor. Other sources of lead such as lead food containers, lead chromate in food colouring and lead medicinal ointments were also recognized and it was observed by one researcher at the time that "the child lives in a. lead world". (12)

At much the same time in Baltimore, USA, there were many occurrences of lead poisoning amongst poor families during the depression years. Most cases were caused by burning discarded storage battery casings for fuel and lead poisoning was referred to as the "Depression Disease". (13) In South Africa, in 1976, six cases of lead encephalopathy (severe brain damage) were reported amongst African children in East London. Three children were visited at their homes, and all were found to have used battery cases in open braziers for fuel. (14) 3

Between 1930 and 1960, in many parts of the world, increased awareness among health workers was associated with an increase in the number of reported cases of lead poisoning. Lead poisoning was thought to be caused largely by the repeated ingestion of flaking lead paint in delapidated housing and was particularly prevalent among socially deprived inner city "slum" children. (15-20) During the 1960's, in countries such as America, mass screening programmes were undertaken to detect such children, who were thought to be at greatest risk.

During the late 1960's and early seventies, it became evident that a history of pica and lead paint in old deteriorating housing could not always be identified, particularly in children with only moderately elevated lead levels. (11,21) Although cases of clinical lead-poisoning had become less frequent, it was evident that there were many thousands of children with moderately high lead levels, associated with only general environmental exposure to lead.

This was of particular concern as reports on "subclinical ll effects of lead in children without symptoms of lead-poisoning had been recently published. It was known that lead at relatively low levels caused certain metabolic disturbances, (such as the inhibition of certain enzymes involved in heme synthesis) but there was now evidence of behaviour disorders and neuro­ logical and psychological impairment in children with only moderately high lead levels. (22,23,24,25) More recent reports have suggested that lead may cause behavioural and psychological disorders in children at even lower levels. (26,27,28,29,30)

It also became evident that the blood lead "levels of urban populations were considerably hlgher than rural populations and that people living next to point sources, such as lead smelters or streets with heavy traffic densities had higher lead levels than others. Levels of lead in the air, dust and soil, resulting mainly from exhaust fumes of automobiles, but also from certain industries, received increasing attention as sources of lead intake amongst children. (31-42)

Young children between the ages of 1 - 5 years have been found to be at greatest risk and studies· have recently suggested that child­ ren might ingest significant levels of lead-laden dust through normal hand to mouth activities. (39-44) Children are generally regarded as being at greatest risk due to the fact that they may be more exposed to lead, they have a greater intake and uptake of lead and they are more susceptible to leads toxic effects than adults.

Of particular importance, however, is the fact that children from socially-deprived backgrounds have continued to have the highest prevalence of increased lead levels. Many recent studies have demon­ strated that elevated lead levels are more common among economically deprived communities (45,46,47,48,49,50) This association was recently confirmed in a nation-wide health survey undertaken in the U.S. (51,52)

Poor children are not only more likely to reside in badly maintained old houses with peeling lead-based paint, or with old lead plumbing, but they may also be exposed to ·greater amounts of dust and dirt in and around their homes, (11) and to dust brought into the house by lead workers on their clothes, shoes and skin. (53,54) They may also· be more exposed to lead from traffic and industry. In 1978 the Ne.! Scientist remarked that lead pollution was partly·a class issue "Airborne lead pollution is not democratic,it falls more heavily on the heads of some communities than others. The children who may suffer excess lead pollution from car exhausts are those living near main roads in the big cities. Broadly speaking, these are working class children ..... " (55)

Nutritional deficiencies known to potentiate lead toxicity are also more likely to occur in poor children. (56) Children with poor diets, 5

deficient in protein and certain m.inerals such as calcium and zinc are more susceptible to leads toxic effects. (11,57) The absence of food is also thought to influence lead absorption and studies have shown that there is an increase in the amount of lead absorbed without food. (58)

The sOcial conditions that favour the ingestion of lead have 'been extensively studied. Characteristics associated with increased lead concentrations 'have been found' to be those that impair the ability of a family to provide the necessary care and supervision for a young child. (49) In short, poverty, with its associated problems of over-crowding, high rates of unemployment, large families, pre­ disposes children to the opportunity for environmental exposure to lead.

SOUTH AFRICA , In South ,Africa, until relatively recently, little was known about childhood ,lead poisoning. It has been said that South Africa may be in a similar position to New York in 1950, when lack of awareness led to only one case of lead-poisoning being reported. (59)

Recently a number of published reports have pointed to the fact that children living in certain areas of the may have lead levels comparable to those of children living in North America and Europe. One study (60) found that certain children in urban Cape Town had accumulated levels of lead in their blood and teeth similar to children living in large western cities. In another study (61) it was found that lead levels in the teeth of some 20 children from a light industry in the Peninsula were lower than those of children living in the vicinity of large industrial plants.

In the course of my research, (62) a cross-sectional analytic survey was carried out on about over' 1 200 school 'entrants from schools in 19 suburbs in the Cape Peninsula. Areas sampled included 6

Central Cape Town, Woodstock, Claremont, Retreat, Elsies River, Athlone, Bellville South, and others (see fig. 1)

The study brought to light variations in ~lood lead levels and zinc protoporphyrin concentration (a constituent of the red blood cell which increases with elevated lead levels) with respect to geographic location. Nearly twice as many children living.in urban-industrial areas had raised ZPP levels compared with children from other areas. The highest levels were found in children attending schools in urban­ industrial areas on major roads.

Children attending two schools in particular, one in Woodstock (an urban area with a light industry sector) and one in central Cape Town, showed a high prevalence of increased lead levels. At the Woodstock school the average blood lead concentration (22ug/dl) was more than twice that of a control school in Rout Bay, a semi rural area (see table 2) The difference in blood lead concentration be­ tween the two schools was found to be statistically highly signifi­ cant. Seventeen percent of Woodstock children had lead levels equal to or exceeding 30 ug/dl, the USA standard, and about a third had levels exceeding the U K safety limit of 25 ug/dl. (There is no universally acknowledged safety level for lead, and the safety thres-­ hold has been continually downgraded in recent years. (63) The concept of a 'safety level' is thus somewhat arbitrary.). The highest lead level amongst Rout Bay children was 15 ug/dl, whilst that of Woodstock children was 41 ug/dl. Isolated cases of high lead levels were also found in areas such as Athlone, Claremont, Maitland and Retreat.

CASE STUDY INVESTIGATIONS The home environments of children with increased blood lead levels (greater than or equal to 25 ug/dl) have been investigated and the results of these case studies are reported here.

Twenty children were visited at their homes, of whom 8 came from

Figure 2.

BLOOD LEAD D!STRIBUTION OF SCHOOL CHILDREN

35

30

'20~15

10

'08 12 16 20 24 BLOOD LEAD CONCENTRATION (ug/dl)

4Sl BLOOD LEAD DISTRIBUTION OF WOODSTOCK SCHOOL CHILDREN 40 1I 3S.J

30

-

10 ----j 5 I I 1 I 12 16 20 24 28 32 36 40 44 BLOOD LEAD CONCENTRATION (ug/dl) 7

Woodstock, 4 came from central Cape Town, 2 were from Claremont and the rest were individual cases from Bellville South, Athlone, Elsies River, Maitland and Retreat. (see table 4)

At each home visited a questionnaire was administered to the parent or guardian of the child, and samples of water, paint, dust and soil were obtained for lead analysis.

Personal interviews with parents or guardians were granted at all homes visited. Information was obtained on the families socio­ economic circumstances, the physical condition of the house (with particular reference to factors wuch as condition of painted surfaces and type of plumbing) and the physical environment (with reference to factors such as position of the house with respect to traffic or industry). In addition, information was obtained on the occupa­ tional histories of the residents in the house, medical and behavioural histories of the children (with reference to factors which might affect exposure, such as pica, primary play site, amount played out­ doors, route travelled to school) as well as information relating to diet, and other factors. (see table 3)

PERSONAL DATA The personal details of children and results of individual blood , analys"s are given in table 4.

SOCIO-ECONOMIC DATA (table 5) The majority of parents or guardians of children had completed, or had partially completed, primary school and were employed as unskilled or semi-skilled workers. Women were mainly employed in the clothing industry or domestic service, whilst men were primarily employed in the building industry as artisans.

The average family income was R246-00 per month, ranging from R130-00 to R385-00 per month. On average, 5 - 6 people were supported on this income. .------,

Personal Data: ~ame, School, Class, AocresE, Se>:,

Date of Birth, Religion, Borne

Language.

Socia-Economic Data: Fathe~'s/Mothe~'s O=cup2tion,

Child~e~, !~umber of ?eople Living

in Dwelling, ~umber of Roo~s iG

Dwelling.

Housing and Bnvironmental Data: Ty?~ cf Dwe}Jin;,

CDndition, Piping, Energ)" SocrCE,

Condition of Painted Surfaces,

Ti~e Si!lCe Last Painted, Position

of Dwellirl~ with Respect to ~;2jor

~C'&8S, :Industry.

to School, Behavioural History

(Evidence of Pica) I 1·~edi~21 Histo~}'

(Number of 8ospit2J hdrni.ssjons),

Behavjoural and l·:edicaJ Histor)! o~

Sjblin~EJ IJutrjtio~; Status, hnloun:

0:' ']'i.IJIJC(~ Food ConsurTiE-c. CouLing II II Utensils, O=cupatjon~] Histc~jcs c~ II TIIJ1LE 4;,: r[.RSClNI\[. D,'l'/\ ~ -,------.--.-.-.. --... Rcsul ts of Blood lined Y""" Child. ---I Sex IIge (yc;oI1:''<;) lIorna L'lI1(jui1gr> Religion I\ddress Sr:hool No. ZPP BPh 11b (ug/g l'lb) (ug/dll (g/dl) P ..1

1 5.2 41 1l.9 M 6 /\frif:",~n" Christi"" \-iO

2 5.4 30 13.9 M 6 I\fril'.'1cHlS Christi"n vlo

3 5.0 33 17 .8 p 7 1\ fri k;lims ChristiCln \'ioodstock 7.

4 5.4 34 U.3 I ~1 6 ,'fri k"'1I1S O,ristian \'inoo,~ t:or.k 2 5 9.0 29 13.0 I n 7 flfri.I·:;I"n" r·luslim loJo()ds tor:k 7.

6 30 p 7 I\[r:j krl~lJlS Christian H;;nover Pk 2 (prev. I 1';()0ds tock ) 7 8.1 34 13.4 I n Ei liEd k",,,n." r·1uslim Care Town 2 8 7.1\ 33 D.G I '-I I) r:r~"'llj.sh Christicm l'locr]s tock 2

9 7.5 28 D.'? 1 I' r, i,\ fi-j k;l;lIlS Christi.i1n !'Ioods tor:k 2

10 9.7 25 13.1 I n Arr j k,-';lIl.S Chr i.f:;. ti0J1 ClP'" Town 9 ______.1 __. __ ..... ______.______. ___ .

e I ...... J Table 4 Continu ... d ------·---·---·------­ Results of Blood I\n"ly" .... " r;,,]igion I\ddres~ School Child ZPP BPb Hb·------Sex I\qe (yenr:-,s) !bm" [._"1'1'.lnQ'" No. 1 (uq/g Bbl (ug/elll (q/el1) I ._------_._.. _-_.

1\ [rik,vln!" Chdstian C<1pe T~l1 9 11 10.1 35 F 8

CnqUsh ~luslim C"[X' To'''Tl 9 12 7.8 44 13.7 ~1 6 I\frik"",ns Christian C;\fY TO\oJn 9 13 6.1 28 D.h t" 9 I\frik;lClns Chdstiiln AthIon", 12 14 27.5 50 9.9 ~1 7 [\8.1.1viUe 6 27 12.6 N 6 f\l:ril{.;vlIls Christiiln 15 8.7 South

christi

~, I\frik

., f\rr:-.ik;=l;~n~ Jlusli.m C)'lrC'nl0nt 3 9 7.3 35 n.s I"

F:ls i.C'~; 1 25 9.0 M ~ I\friJ«.t

1 Careta!.;er/ Home Suh Fl ~1:c1. ~ RJ 10,00 4 3 hand}'l11Cln I 2 Dock worker Sweet factory Std. 5 StcL ,5 R3J;>, ()O 5 4

3 Cleaner flame std. 8 Std. 5 R236,00 R7.50 13 1

4 Sea Patrol Home Std. 3 S Iccl. 7 1<770,00

5 Prison Home Std. 6 Std. 2 RUO,nn 11 2

6 Cleaner Home Std. 3 St(l. 4 RWq ,DO R33-00 5 3

7 Prinl:ing '.":1 rri~"l M'ltric ::::tel. 8 RSO-OO 7 4 h'fl\ k:1

n Fork I i r ,-, IInm,' H17~ ,1)0 H7fl-,I)() ·1\ I ... ·, St.d 5 ~'·rl. 5 II J

y L,;\LI<.;)\.l1:'~r el r )l.',111" ::1,1. I'; ':1<1. 1:?,1'J , I! II 1')11 fit) 7 ) factory 10 Labourer Borne Std. 4 Std. 3 Rl fll), no R?4-00 6 :\ (plumbing)

--- ... _._-----.---_.- , ,.

(T~b18 5 cnntinup01

• Father's Mother' " Father's r,k..,thr:-l:- t,'; F,lrni 1 Of Tncomn P"'nt I'Jl1!nh(,C" c{ Number of rOQrr,~ Occupation OcC1Jp~ tj.on Educatn. F:cll)c'ltn. (prJ: month) ([Y:'r month) pr·010 1.", p:>r c]"'P11i.ng per dwelling I _._------_._-----..... __.-._----_ .. _---_._------.... 11 Plumber Home. St.d. 6 ~; Lri . R360 - 00 F13··(lr)

12 Painter· Home Std. 1 ,SI-e]. S R?60 -·00

13 Driver Home Std. 7 Std. 6 R3GO -00 IW1-OO

14 Flasterer Domestic Servo Std. 4 Std. 5 R200 -00 1<62-00

15 Bricklayer Domestic Servo Std. 7 Std. I) RDO -00 H45--00

16 Caretaker Clothing None Std. I) R140 -00 R30 -00 factory 17 Painter Home Std. 5 S tel. 6

18 flome ;~ r:.r1. 6 Rl7.1. .. 00

19. Gardener Clothing None Stcl. I) R385 -DO [,9-00 factory 20. La.bourer Domes bc Serv. Std. 4 St.cl. 3 R21S -00 1<6,40 L __ _ 8

The majority of families lived in rented flats or houses, whilst one family lived in a tin shanty. The average rent paid was R29-00 per month, ranging from R6.40 to R62-00 per month.

Many of the families lived in overcrowded conditions, with an average of 7 - 8 people living in three-roomed flats or houses. A third of the homes had ten or more inhabitants. In one particu­ lar case, 13 people lived in a one-roomed flat.

HOUSING CHARACTERISTICS (table 6) The majority of houses, particularly those in Woodstock and central Cape Town, were over fifty years old and were considerably dilapidated. Most had no electricity supply and used paraffin or gas for fuel. Many of the homes were dark, poorly ventilated and very dusty.

All houses had internal copper piping, with the exception of one house which had galvanised iron pipes.

In many of the houses, the exterior walls had a significant degree of flaking paint, but the interior surfaces were mostly intact. Usually only one or two flaking surfaces could be found. One house however, had nearly all its interior walls in a flaking condition.

PHYSICAL ENVIRONMENT (table 6) Most of the children lived in mixed residential/urban-industrial areas such as Woodstock and central Cape Town, whilst others lived in various residential suburbs throughout Cape Town. The majority of the children lived in the near vicinity (about 500m) of the school they attended.

Most children did not live directly on major raods, but lived between 50 and 200 meters from such roads. Many lived in close proximity to small factories such as spray painting, automobile body works and TM1I.,r: 6, 1I<'llS Hi" I\Nf)~fc;',.'Jpni·;nl·:~:TIIJ., nr,'rr, r . ---_ .. _----_._----_._- ~------.- -\ No. Condi tion of. 0<4elling (with I.'o.si bon of D<4elling ',:i th respect to m

I I-lell main tained > 50 ye'lrs Cu Electri.ci. tv L 50 metres from rElilwElY line, L 50 m from mi'ljor cOeld, < 20 m from ElU tomobile body works.

2 Interior well maintained, ) 50 yeclJ:s eu Oil, p;lI-flfCLn 50-200 m from m~jor rOElel. exterior deteriorating, flaking.

3 Very badly maintained, dila- > 50 ye'lT,S Cu Gas, p"raff.ln 50-200 m from mi'ljor road. £ 50 m from auto- pidated. Ceiling flaking. mobile body works.

4 Badly maintained, dilapi­ > 50 yeClP; Cu GrlS On m;ljor road. ~ 20 m from sheet metal works. dated, exterior flakin?

5 Badly maintained, dilapi­ > 50 yeClrs Cu GClS, pclr 200 m from major road. dated. Isolated flaking surfElces

6 \;e11 mi'lintained L 20 ye'lrs Cu rClrClff.i.n > 200 m from major rOClel.

7 In terior very well main tained > 50 yea rs Cu l~l PC trici. ty > 200 m from major road. exterior deteriorating, fJ aking

8 Badly maintained, dilapi­ ) 50 years Cu 1-1oocl, p;'rClffin 50-200 m from mClor road. ~ 50 m from railway lin!?' da ted . Windowsi.ll flaking ~ 20 m from sheet metill works.

9 Quite well maintained >50 yeC1rs Cu Elec trici ty 50-200 m from major road. ,[ 50 m from railway line. -: 20 m from sheet metal works.

10 Interior quite well main­ > 50 yeCl"-; ell Gas >200 m from mCl:jor rOCld. < 20 m from garElqe. t,l'ined, isola ted flClking , sur filces . F:x 1:0cior eli J.upicl" ted. T'3b} e 6 COil t-inu<:"J position of [)v;elling ·,:i.th r,,'iV''-\: to m"jor No. Condition of [r,,,,,,lling (Hlth Age of DI""'lling Firi.nq Fnerqy ,~;ourc'" rOncH s) 'Jllo) indus try. ref. to pMin ted sur.f'3ces) -1 \ ! > 7.00 m from mnjor rOndo ) 50 ycrtrs C:1J G;:lS 11 Interior quite well main­ till.ned. exterlor deter­ iorCltinq. Isolated flaking ·surfClCCS 01 m"jor raCld, .t. 20 m from s['ray painting Clnd f.) ectrici ty > 50 YE''''S C1.l 12 very Hell maintained l;.ar:ly \\'()ck,r::;. /. 50 m from major ro;'1(}. ) 50 ye',rs eu G7lS 13. Interior quite well rnain- t~ined. F.xterior de- teriorating. ( 50 m from major rOrid. Cl.:' El",c~Ticit:y 14. \':ell maintained ) 50 'i",,,rs > 200 m from major road. 50-200 m from ') 50 verirs Cu F.lrw.tri.cit)' 15 Well m"intainecl shooting range.

200 m from major r(,Md. G"lv. E) C'ctricit·y > \'Iell mClintainecl. t.. 40 YE""S 16. iron r-:J r'''rl-l:"i ri !:'-l > 200 m from major roOl'1. ?(l Y"'Clrs C'J 17 \'jell m~int"ined z \",,,,, -)() 7nn HI rOt (.m m;\"jtH" rr)"l,l. 1 ',f) , " Ifl I("d I Y ,,, .. Ill'" 111'''-'. dJ.1 "1"1·· , r\.ll"r.rl. Tnlrr"jnT' :-mr-l r.x-­ terioI' Sur,[;:lces fl~lking.

\1j0~J 50-.200 m from major ro;:d. > 50 \,C'rlr::; Cu 19 Interior quite well mriin- tained. r.xterior di.la- pid" t""'l. flaking r;:1c,-d'r: ;\ :;> 200 m from major ro,,']. very bCldly ,naintained, di­ /. 20 y<'ars lapida ted shCln ty. Isola ted to flaking surfaces __ I ------~------.--.-- ... ---.------~-.. --- -_.-

Ia. • ;1 9 sheet metal works. Some of the Woodstock children lived within 50 m of the railway line.

BEHAVIOURAL AND MEDICAL FACI'ORS (table 7)

The majority of the children played primarily outdoors, in the immediate vicinity of their homes, many in busy roads. Most children walked to school, often along busy roads in peak hour traffic.

Three children exhibited evidence of pica, whilst one child showed·a,marked tendency to mouth objects. Children showed evidence of pica 'for items such as paper, sticks, earth and matchsticks. NO children showed evidence of pica for paint.

Fifty percent of the children had been admitted to hospital at some stage Of their lives, mainly for chest problems such as bronchitis. No children had previously been investigated for lead poisoning.

NUTRITION (table 7)

From superficial questioning, it appeared that most children received adequate nourishment. Two children, however, had abnormal eating habits, eating no meat or veget,ables, and one child was extremely malnourished, ea~ing primarily mealie meal.

The majority of children ate little or no tinned food, apart from two children who received tinned food daily to supplement their diet.

All families used aluminium pots for cooking and no pottery or ceramic-ware was used for cooking or storing food in. Til P I.F: 7 nl~11/\VtOURIlL liNn OTIlEY DATil ------_._------PO\lte Tr;well(Vl Evi(jenc'? "'r.ount or Tinned \';"rkers in '-'=';'1'1 No. IImount P1ay0d Otlto00rs Primary PlilY Si h' ~l\l tri tion St'l tus t,;) School of P:i.ca Focx] E"ten Pe 1a ted InrJus t .

1 ~lajori ty of free time PClckyaro son In i1lClll~_l SrI t i~f;:)c tor.y Jnsiqnificilnt maior. [(-"-1(1

2 Majority of free time PClckVilrd ) SOO m ell onq S'ltisf"ctory lnsiqnificant ",'lj0t:' rO~ld

3 IIpprox. half of free Side street, SOm > 500 m along S'1 tis Lv:: tory (-! ) Ino.i.qni fi ("~H1t time from hor.)e mTior rOild

4 Majori tv of free ti.me Miljor rOCld 10(1- son m along Siltj"f'1ctory(?) Insi';1nific;,n t 200 m from hom!" m'1jor rC'ld

5 Majority of free time BackVClrd 5(10 n, illong S'ltisfClctory(?) In'; iqn1 fi.c;,n t ",,,·kr ro"d

6 MCljority of free time Yard 701'-500 m "hm':! S"tisfilctorv Tinne:i fcxxl I m~ljc(" r02d caily

Majority of free hme Y"re] ?OO-SOO m ,,10nq ~;, ti.o:-;f.-)I':. tory Jnsiqni.fiC;;tnt \7. TTl;1 JOT:" r-:VlC]

I 8 MCljority of free time 11;lckYClrd, side J 00-700 to ,,)onq E.• t~ n,,:~ rn(:'u t Insixlni.fican t streets, 100-7.00 m;:\ j C' r n.v·l(l ("'~- \i~10t:'~lbl('s "' fr.-om home

9 ~lajori ty of free time P.;"lCkY;;lrd l(l('-~()O "' ,,1ono F;lI·" 11') cn::lkM Tinn",l reod Spr'-lY pClint"r/ m;tjnr rn;'ld In"'-l {. (r~::.;h d'li.)y pCln'?l i)0<1t('r '!··... ::.I ..... ':;,h1. r).'..;

10 IIpprox. hCllf of fr<::-e B,",ckyard, sine l(IO-?llf) In ;:l]cmq 1-"11": ;.[ .. ;.:;l~·i.::;f;l( .. ~(·~rv I:n"iqnific'lnt time ~tr.eet:!= rn;., j.·.. ")r r n,~,\d r."'r·, :~ I i.'-:k.'7. . Il. __ _ ,l·i,!· . "._-_.. - -.----

-, .. ·,...... nn ...... ______~ __------,

Ti'lblp. 7 Continu<'cl

Houte Tr;:wplled F.~,1c1l?nc:r-' I\mount of Tinned 110rkers i.n Leild no. IImount Played Outdoors P.r.im;;lt"y rlc\~' :;;i. \"17' Nutri t.Lon Stab.. l.~ 1:0 Sci lc)"_'d. () f r i.r:;·r Fooo ""ten Related Indust

11 Mnjority of free time Sid,? ~; t r"E'(' t.~-: J P0M¥?(tO m ;110119 r"01Jt"h:~ S,-1 t:i .<::', f;)c toe',' InsignHir:ant approx 50 In fn'," rWl :inc rO;1"l ob}~r. t :::; home ~l)r::h ;1.', b'll V~n,;, 1>-,-"1,,

12 Less th,1n h'llf of Inside ~ I)IJO m (llonCl 8;·1\-.':; Sa ti.~ f.;v'I-.or.y InsiqnH.i.cElnt free time P";lj':'lC rn.=t~l F",Cnl" .c:l-jr:!-:·;

l3 Majority of free time Side streets 100- <. "i0 m alonCJ Si1ti..~flv:t()ry Insignificimt ! 200 m froJ11 h0,"'" m.:ljOr. rOAd t I 14 IIpprox. haH of free Yi'lI:o 200-500 In ;,lona 1':.11-,~ Si1 tisfac tory Insiql1i.fi.cllnt time mFl jot ro.:rl m,' t(~ly~.,,;

-f 15 Majori.ty of frep. time Gr-()unds of shoot- Satisfactory Insiqnifioin t I in'] r8l1g'" , 200- t 500 J11 from hCllne i I I 16 ~lnj()ri ty of fr"e tilll'~ (~.'1 r(:1t:·~n S"tisfar:tory In~iqnifjcant

17 ~Iajority of free time Y'lrcl 100-200 m "long lit"'" tisfactory Insiqnific;lnt I miljor road I I 18 Less than half of In~icle (50 rn along Satisfllctory Insiqn.ific,"Illt free time m"jor ro,lC) I 1 19 Najority of free time S;Jc street!", JAr.> (5~ In ?long S"ti.o;r;"ctory Inl'Jiqni rici1nt

1 olltcbors -200 m {rom honK' m"Jor rOllo

20 l'l"jorHy of [poe time 'filrc 100-/.00111 "long 'Siltisfi

OCCUPATIONAL HISTORIES (Table 7)

With the exception of one resident who was employed as a spray painter/panel beater, employees were not occupationally exposed to lead.

ENVIRONMENTAL LEAD ANALYSES

Water

Although no houses had lead piping, it was decided to test water samples for lead, as there was the possibility that old lead piping may have been present beneath the ground. (Lead piping was regularly used for plumbing during the first half of this century, but most pipes have since been replaced. The demolition of District 6, however, revealed that many houses still had lead piping).

Analysis of water samples revealed that insignificant amounts of lead were present. Lead concentrations were well below internationally accepted safety levels.

Paint (Table 8)

Analyses of paint samples revealed variations in lead content between houses and within houses. The average lead content of samples was 1.7%, ranging from .02 - 11.4%. Lead concent­ ration was highest in samples from wooden windowsills, doors and ceilings; the average lead content in these samples was 5%.

Approximately 90% of the samples had lead levels above the U.S.A. safety limit of .06%.

Soil and Dust (Table 9)

The lead content in all but one of the soil samples were well above natural soil lead concentrations, estimated to be in the range 2-220 ppm. (In South African soils the natural concent- ration level is estimated t9 be 12 ppm) (64). TABLE 8 . RESULTS OF PAINT LEAD ANALYSES

Paint J_edd cO:"j_· Child Sample Description No. centration (~;)

1 Bedroom (cream .07

2 Ki tchen (green)

Outside door (green) 1.6

3 Ceiling (bro\,'n) 4.9

Outside (blue) 1.6

Lounge (cr~am) .06

1 '. 1

Be6.:-ooii! (blue} .18

Outsioe (green) 2

Outer v:indo"\.",'sill (blue) 11. 4

.6

Cutside (blue) .23

E· Lounge (blue) .03

Lounge ~indowsil1 (blue) 3.5

9 Bedroom windowsill (green) 5.0

Outside (v.'hite)

10 Out.side (pink) 3.8

Bedroom (cream) .08

Halh.'ay (pink) 1

11 Lounge/bedroom (cream) 5.9

Ki tchen (cream) .4

Outside door (silver) 3.8 Table 8 Continued

Child .' Paint lead con- Sample Descr:i,ption No. ccntration (%)

12

13 Halh,ay (red) 1.2

Kitchen (blue) .08

Bedroom (blue) .46

14

15 16 • 17

18 Kitchen (grey) • :<

Outside (brov,'D ) 1

Bedroom (bro-;vn) .02

Lounge (grey) .02

19 Kitchen (cream) 1.8

Outside (white) .02

Lounge (cream) 1

Bedroom (cream) .2

20 LEAD A"ALYSES RESULTS OF SOIL AND DUST TABLE 9. Lead Lead Dust Soil Concentr-ation (ppm) Child No Concentration (prm)

2600 1 400 2 460

3 390 1300 4 100 5

6 1500 7 2100

8 23 1000 • 9 1000 20e 10 910 150CJ 11 710 300 I lL \ 900 I 13

\ 14

1:' \ I I J6

1-7 800 \ 18 380 2000 19 5000 l 20 11

In fifty percent of the dust samples, the lead content exceeded 500 ppm, the U.S. safety level for lead in dust.

DISCUSSION

Home investigations revealed that there was no immediately obvious local source of exposure, such as children with pica for paint, or drinking water with a high lead content.

Nevertheless significant levels of lead in paint were found and it is thought that this may be a significant source of exposure in younger children, between the ages 1-3 years, when pica and normal hand to mouth activities are most conunon. Unlike countries such as the U.S.A. where the lead content in paint is stringently regulated by law, there are no regulations for lead in paint in South Africa. Cheaper low grade paints in particular, which are likely to be used by people investigated here, may contain up to 25% lead. In certain primers, lead pigments may contain 60% lead (65)

The high lead content in certain soil and dust samples may reflect some contribution from flaking paint, but it is thought that the contribution of airborne lead, particularly in the Woodstock and central Cape Town areas, is likely to be substantial. As petrol-derived lead constitutes the major proportion of airborne lead (64) and many children lived in areas of heavy traffic densities, the contribution from this source is likely to be significant. (S.A. has one of the highest levels of lead inVpetrol in the world.(69) In addition, there may also be contributions to soil and dust lead levels from industrial sources of lead, such as garages, automobile body works and sheet metal works.

It is felt that the particular social circumstances in which 12

the children investigated live, are likely to be important factors in predisposing children to uptake from environmental sources of lead, and in potentiating lead toxicity. For instance it was evident that most children lived in extremely poor soci-economic conditions. It has been estimated that the minimum subsistence level for a 'coloured' family of five, living in Cape Town, is R231-00 per month. (67) Most parents had only primary school level education and were living close to, or below this subsistance level.

Studies from other parts of the world have shown that children from economically deprived backgrounds have higher prevalences of high lead levels (see page 4 ). In a recent U.S. survey, it was shown that children from low income groups had a significantly J higher prevalence of elevated blood "lead levels than those from moderate or high income groups. For instance amongst children from families of low incomes, there were approximately nine times more children with elevated lead levels than there were among children from families with higher incomes. (51) 18.5% of poor, black children were found to have blood lead levels greater than 30 ug/dl, the U.S.A. standard. (52)

Another study which tested a representative cross~section of children in Connecticut, U.S.A., found an inverse relationship between median blood lead levels and socio-economic status. The distributions of blood lead were such, that 5 times as many children in the lowest S.E.S. census tracts had high lead levels than children "in the high­ est S.E.S. census tracts. (47)

Not only is there evidence of greater acute e~posure in poor children, there is also evidence" of an association between poverty and chronic lead exposure. This was recently demonstrated in a study which showed that dentine lead levels were highest amongst children living in low-income areas. (26)

Particular social characteristics which have been found to be associated with increased risk of lead absorption include large family Size, 13

inadequate parental sup~rvision, disturbed mother-child relation­ ships and underemployment. (20,22,45,49,50) Most of these factors were seen to be operative in the cases investigated here; the general picture being one of children living in overcrowded, impoverished conditions, with little supervision and with plenty of opportunity for exposure to and uptake of lead from their environment. These factors were likely to have presented children with more opportunities to play in lead-rich dusty environments - both inside and outside of the home, at school and walking to and from school.

There is some evidence that pica in children (seen in three children here) is associated with emotional stress, disruptive home situations and inadequate parental care. (20) When such a child is exposed to environmental sources of lead, such as soil and dust, the risk of poisoning is increased.

Nutritional deficiencies may also have played a significant role in several children's increased lead. intake, particularly in the mal­ nourished child from the outlying area of Retreat. Not only are certain mineral deficiencies known to potentiate lead toxicity, but so is the absence of food. (see page 5) Thus children with pica, or children who play in areas with high lead levels, may swallow particles containing lead many hours after their last meal. In addition, there may be high lead levels in certain foodstuffs, particularly canned foods, (68) which may have been of significance in two cases at least. One may have expected that in most families where few had an electricity supply and most had no fridge, canned foods would be frequently consumed. This appeared not to be the case in the majority of families, however, which was probably due to the fact that canned foods were too expensive for these very low­ income families.

It was thus evident from the Case study investigations carried out 14

that exposure in most children is likely to be multifactorial, depending on individual environmental and social circumstances. Although further detailed environmental investigations of cases (and of controls) are needed in order to determine the relative importance of various sources of exposure, it is apparent that the adverse social and environmental conditions prevalent among economically deprived children such as those investigated in the study, are likely to be responsible for their increased lead intake.

It is recommended that legislation be introduced to limit lead exposure in the environment. In particular, legislation limiting the lead content of petrol and paint, along the lines of that in the U.K. and the U.S.A., is needed. Protective legislation is also urgently needed to limit lead exposure and absorption in the work­ place.

It is also suggested that a major educational effort be directed at the community and to the political structures that relate to the ,community, to make people aware of the hazards and sources of lead exposure.

Most important, however, is the fact that unless such measures are accompanied by fundamental social changes in South Africa, the health of the community will continue to be compromised. REFERENCES

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62. Von Schirnding, Y. "A Study of the Impact of Lead in the Environ­ ment on School Children in the Cape Town Area." Unpublished M.Sc. Thesis. , 1982.

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64. Nriagu, J. "Properties and the Biogeochemistry of Lead". In Nriagu, (Ed): The Biogeochemistry of Lead in the Environment. Elsevier, Holland, 1978. 65. Representative, South African Bureau of Standards. 66. Nriagu, J. "Lead in the Atmosphere". In Nriagu (Ed): The Biogeochemistry of Lead in the Environment. Elsevier, Holland, 1978. 67. Horrell, M. Survey of Race Relations in South Africa. South African Institute of Race Relations, Johannesburg, 1981. 68. Settle, D. and Patterson, C. "Lead in Albac'ore: Guide to Lead Pollution in Americans." Science, 207 (14 March): 1167, 1980. 69. Ninth Report of the Royal Commission on Environmental Pollution: Lead in the Environment. Her Majesty's Stationery Office, London, 1983. These papers constitute the preliminary findings of the Second Carnegie Inquiry into Poverty and Develop­ ment in Southern Africa, and were prepared for presen­ tation at a Conference at the University of Cape Town from 13~19 April, 1984. The Second Carnegie Inquiry into Poverty and Develop­ ment in Southern Africa was launched in April 1982, and is scheduled to run until June 1985. Quoting (in context) from these preliminary papers with due acknowledgement is of course allowed, but for permission to reprint any material, or for further infor­ mation about the Inquiry, please write to: SALDRU School of Economics Robert Leslie Building University of Cape Town 7700

Edina-Griffiths