Dermal Exposure Related to Pesticide Use - American Chemical Society

and the Mine and Health Safety Administration have contributed a considerable .... b i l i t y o f various f a b r i c s by d i f f e r e n t classes ...
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28 Protective Clothing and Its Significance to the Pesticide User 1

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RICHARD V. MORASKI and ALAN P. NIELSEN 1

Office of Health and Environment Assessment, Office of Research and Development, Exposure Assessment Group, RD-689, Environmental Protection Agency, Washington, DC 20460 Office of Pesticide Programs, Hazard Evaluation Division, TS-769C, Exposure Assessment Branch, Environmental Protection Agency, Washington, DC 20460

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Until recent years, research devoted to the pesticide exposure of agricultural workers was essentially nonexistent. It has been established that a major source of exposure to toxic chemicals i s the use of such chemicals in agricultural production. In general, applicators and mixer/ loaders have the highest exposure r i s k . Many studies have shown the exposure to applicators' skin to be well over 90% of their total exposure. The only significant type of barrier available to applicators to reduce dermal contact and hence exposure i s protective clothing. Current chemical protective clothing technology clearly demonstrates the lack of knowledge and sound data to permit accurate and appropriate regulatory decisions i n regard to specific personal protective devices for various exposure scenarios. Significant work on the effectiveness of personal protective devices in reducing pesticide exposure has recently been initiated. This paper reviews the current state-of-the-art knowledge of protective clothing technology and reviews the research being conducted in an effort to develop protective clothing recom­ mendations with regard to pesticide users. P e s t i c i d e s are chemicals t h a t are i n t e n t i o n a l l y introduced i n t o the environment f o r the c o n t r o l o r d e s t r u c t i o n o f p e s t s . In a g r i c u l t u r e , p e s t c o n t r o l i s deemed i m p o r t a n t n o t o n l y t o produce more food but t o produce a food p r o d u c t o f h i g h e r q u a l i t y . W i t h a t l e a s t 1400 c h e m i c a l s s e r v i n g as a c t i v e i n g r e d i e n t s , more t h a n a b i l l i o n pounds o f p e s t i c i d e p r o d u c t s i n v a r i o u s f o r m u l a t i o n s a r e used y e a r l y i n t h e U n i t e d S t a t e s U ) . A p p l i c a t o r s , m i x e r / l o a d e r s , and workers who e n t e r t r e a t e d a r e a s t o p e r f o r m t a s k s such as hand h a r v e s t i n g , c u l t i v a t i o n and i r r i g a t i o n c h o r e s , s c o u t i n g , t h i n n i n g , maintenance, and many o t h e r o p e r a t i o n s , may be exposed t o p e s t i c i d a l residues. The i n t e n t of t h i s paper i s t o p r e s e n t an o v e r v i e w o f the c u r r e n t p r o t e c t i v e c l o t h i n g t e c h n o l o g y as i t a p p l i e s t o p e s t i c i d e a p p l i c a t o r s and r e l a t e d w o r k e r s . This chapter not subject to U.S. copyright. Published 1985, American Chemical Society

396

DERMAL EXPOSURE RELATED TO PESTICIDE USE

By law t h e EPA i s mandated t o c o n t r o l exposure t o c h e m i c a l s u b s t a n c e s i n c l u d i n g p e s t i c i d e s . The F e d e r a l I n s e c t i c i d e , F u n g i c i d e , and R o d e n t i c i d e A c t as amended [FIFRA: §3(d) (1) (c) ( i ) ] and t h e Code o f F e d e r a l R e g u l a t i o n s - T i t l e 40 (CFR-40: §162.10, 162.11, 170.2, 171.2, 171.4, and 171.5) s t a t e t h a t EPA must e s t a b l i s h t h e c o n d i t i o n s under w h i c h p e s t i c i d a l c h e m i c a l s a r e p e r m i t t e d t o be u s e d . Each use o f a p e s t i c i d e r e q u i r e s i t s own r i s k assessment which i s an e x p r e s s i o n o f t h e a c c e p t a b l e l e v e l s o f p e s t i c i d e exposure. Since the p r i m a r y h a z a r d a s s o c i a t e d w i t h t h e use o f p e s t i c i d e s i s the c h e m i c a l i t s e l f , t h e p o t e n t i a l f o r i l l n e s s v a r i e s w i t h t h e l e n g t h o f exposure and t h e t o x i c i t y l e v e l of t h e p e s t i c i d e ( 2 , 3 ) . I n g e n e r a l , e x p e r i ence and r e s e a r c h have shown t h a t a p p l i c a t o r s and m i x e r / l o a d e r s have t h e h i g h e s t exposure r i s k . T h i s i s e s p e c i a l l y t r u e o f i n d i v i d u a l s who perform b o t h t a s k s . They must d e a l w i t h exposure t o the concent r a t e d f o r m u l a t i o n s w h i l e m i x i n g / l o a d i n g as w e l l as t h e d i l u t e d chemical during spraying operations. Exposure R e d u c t i o n P e s t i c i d e s may e n t e r t h e body through t h e mouth, l u n g s , and s k i n . The r o u t e o f e n t r y o f g r e a t e s t s i g n i f i c a n c e t o t h e p e s t i c i d e u s e r i s e n t r y through t h e s k i n . I t i s w e l l documented t h a t percutaneous a b s o r p t i o n o f p e s t i c i d e s does o c c u r ( 4 , 5, 6 ) . Dermal exposure t o p e s t i c i d e s , e s p e c i a l l y t o t h e hands, u s u a l l y a c c o u n t s f o r more t h a n 90% o f t h e t o t a l exposure r e c e i v e d ( 7 , 8, 9 ) . Exposure through i n h a l a t i o n r a r e l y a c c o u n t s f o r more t h a n 10% o f the exposure r e c e i v e d ( 7 , 8, 9 ) . The one major e x c e p t i o n t o t h e s e f i g u r e s i s f u m i g a n t s which a r e v o l a t i l e and a c u t e l y t o x i c through i n h a l a t i o n . Even though t h e N a t i o n a l I n s t i t u t e o f O c c u p a t i o n a l S a f e t y and H e a l t h and the Mine and H e a l t h S a f e t y A d m i n i s t r a t i o n have c o n t r i b u t e d a c o n s i d e r a b l e e f f o r t i n the development o f r e s p i r a t o r y p r o t e c t i o n , i t s h o u l d be noted t h a t v e r y l i t t l e work has been done t o determine t h e e f f e c t i v e n e s s o f r e s p i r a t o r s a g a i n s t p e s t i c i d e s . The l e a s t s i g n i f i c a n t mode of e n t r y d u r i n g s p r a y o p e r a t i o n s i s through t h e mouth (10). O r a l exposure u s u a l l y o c c u r s as the r e s u l t o f i n g e s t i o n caused by a c c i d e n t a l s p l a s h i n g of l i q u i d i n t o t h e mouth o r by w i p i n g t h e f a c e w i t h contaminated c l o t h e s , g l o v e s , o r hands. Any b a r r i e r , t h e n , t h a t can be p l a c e d between t h e w o r k e r and t h e c h e m i c a l t o r e d u c e c o n t a c t w i t h i t , s h o u l d reduce t h e exposure l e v e l and i n c r e a s e t h e m a r g i n of s a f e t y a s s o c i a t e d w i t h i t s use. Our assessment o f a v a i l a b l e t y p e s o f p r o t e c t i v e equipment i n d i c a t e s t h a t t h e r e a r e o n l y two s i g n i f i c a n t means f o r r e d u c i n g w o r k e r exposure t o p e s t i c i d e s . One i s t h r o u g h t h e use o f p a s s i v e p r o t e c t i v e d e v i c e s such as c l o s e d systems. C l o s e d systems have t h e p o t e n t i a l f o r e l i m i n a t i n g exposure during m i x i n g / l o a d i n g . Closed s y s t e m s , however, do n o t p r o v i d e t h e a p p l i c a t o r w i t h any p r o t e c t i o n and, because of some u n r e s o l v e d t e c h n i c a l problems Q l ) , t h e y a r e n o t u n i v e r s a l l y a v a i l a b l e o r a c c e p t a b l e . The o t h e r i s through t h e use of p e r s o n a l p r o t e c t i v e d e v i c e s such as p r o t e c t i v e c l o t h i n g whose purpose i s t o s h i e l d the body from dermal c o n t a m i n a t i o n by p e s t i c i d e products. P r o t e c t i v e c l o t h i n g o f f e r s t h e most i m p o r t a n t means f o r m i n i m i z i n g exposure t o p e s t i c i d e s d u r i n g almost any o p e r a t i o n i n v o l v i n g t h e s e c h e m i c a l s . However, t h e p r o t e c t i v e c l o t h i n g may

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i t s e l f became a h a z a r d by i t s f u n c t i o n a l and p r a c t i c a l l i m i t a t i o n s , such as poor d e s i g n , l a c k o f d u r a b i l i t y , and i n a b i l i t y t o be decontaminated. These and o t h e r f a c t o r s i n c l u d i n g t h e r m a l d i s c o m f o r t , c o s t , o r l o s s o f d e x t e r i t y may p r o v i d e t h e r a t i o n a l e f o r workers not w e a r i n g o r removing p o r t i o n s of t h e i r p r o t e c t i v e o u t f i t s . C a r e l e s s ness w h i l e u s i n g p e s t i c i d e s , improper use and inadequate c a r e o f p r o t e c t i v e equipment may a l s o c o n t r i b u t e t o reduced l e v e l s o f p r o t e c t i o n . I n r e c e n t y e a r s , t h e development of new t y p e s o f p r o t e c t i v e c l o t h i n g , which a r e c l a i m e d by t h e m a n u f a c t u r e r t o be l i g h t w e i g h t , c h e m i c a l r e s i s t a n t , s t r o n g , and d i s p o s a b l e , has p r o v i d e d the needed s t i m u l a t i o n toward t e c h n o l o g i c a l advances i n t h i s a r e a . P r o t e c t i v e C l o t h i n g Assessment A s s e s s i n g p r o t e c t i v e c l o t h i n g t e c h n o l o g y has beccme a m a j o r i n i t i a t i v e o f the Agency. I n 1981, a P r o t e c t i v e C l o t h i n g Working Group (PCWS) was e s t a b l i s h e d w i t h i n t h e O f f i c e of P e s t i c i d e Programs (OPP) t o e v a l u a t e t h e complex problems a s s o c i a t e d w i t h d e v e l o p i n g p r o t e c t i v e c l o t h i n g performance s t a n d a r d s . The e f f e c t i v e n e s s o r a v a i l a b i l i t y o f b a r r i e r s t o reduce o r e l i m i n a t e r e s p i r a t o r y o r o r a l exposure a r e not w i t h i n the scope o f t h i s e f f o r t . I n i t i a l e f f o r t s f o c u s e d on a s s e m b l i n g i n f o r m a t i o n on t h e a v a i l a b i l i t y o f p r o t e c t i v e c l o t h i n g . The " C a t a l o g o f P r o t e c t i v e C l o t h i n g / S a f e t y Equipment f o r t h e P e s t i c i d e A p p l i c a t o r " (12) p r o v i d e s f o r each e n t r y such as p r o t e c t i v e c l o t h i n g , r e s p i r a t o r y p r o t e c t i o n , and s a f e t y equipment, i n f o r m a t i o n w h i c h i n c l u d e s : a b a s i c d e s c r i p t i o n of t h e p r o t e c t i v e measure i n terms o f f u n c t i o n a l and p h y s i c a l c h a r a c t e r i s t i c s ; recommended u s e s ; work p r a c t i c e s o r p r e c a u t i o n s r e l a t e d t o use; p r a c t i c a l e v a l u a t i o n s ; c o s t s ; advantages and d i s a d v a n t a g e s ; m a n u f a c t u r e r s and d i s t r i b u t o r s ; and r e f e r e n c e s . The i n f o r m a t i o n assembled suggested t h a t p r o t e c t i v e c l o t h i n g and i t s e f f e c t i v e n e s s a g a i n s t p e s t i c i d e s had not r e c e i v e d much a t t e n t i o n by c l o t h i n g manufacturers. To d e t e r m i n e t h e e x t e n t of p r o t e c t i v e c l o t h i n g r e s e a r c h b e i n g c o n d u c t e d , an e x h a u s t i v e l i t e r a t u r e s e a r c h as w e l l as p e r s o n a l communication w i t h those i n the f o r e f r o n t of p r o t e c t i v e c l o t h i n g r e s e a r c h r e s u l t e d i n a second document c a l l e d "Summary o f R e s e a r c h on P r o t e c t i v e M a t e r i a l s f o r A g r i c u l t u r a l P e s t i c i d e Uses" (13). T h i s document p r o v i d e s summaries o f p a s t and c u r r e n t ( t h r o u g h 1982) r e s e a r c h i n p r o t e c t i v e c l o t h i n g and r e l a t e d a r e a s . A l i s t i n g o f a l l the i n d i v i d u a l s c o n t a c t e d i s i n c l u d e d . Based on t h e i n f o r m a t i o n gathered, suggested research t o p i c s are i d e n t i f i e d f o r c o n s i d e r a t i o n . Some o f t h o s e a r e a d d r e s s e d l a t e r i n t h i s paper. A t h i r d document was r e c e n t l y completed w i t h i n the EPA. The "Guidelines f o r the S e l e c t i o n of Chemical P r o t e c t i v e C l o t h i n g , " (14) f o r E P A s O f f i c e of O c c u p a t i o n a l H e a l t h and S a f e t y i s d i v i d e d i n t o two volumes. Volume I i s i n t e n d e d t o be used as a f i e l d manual w h i c h p r e s e n t s c l o t h i n g recommendations f o r about 300 c h e m i c a l s u s i n g f o u r t e e n garment and g l o v e m a t e r i a l s . Volume I I d i s c u s s e s p e r m e a t i o n t h e o r y and t e s t methodology and i s more t e c h n i c a l i n c o n t e n t . The p r o t e c t i v e c l o t h i n g reccmmendations f o r p e s t i c i d a l compounds found i n the G u i d e l i n e s once a g a i n h i g h l i g h t the f a c t t h a t l i t t l e r e s e a r c h work has been done i n the a r e a o f p e s t i c i d e s and p r o t e c t i v e c l o t h i n g . 1

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I n a d d i t i o n t o t h e s e e f f o r t s , t h e PCWG has been w o r k i n g v e r y c l o s e l y w i t h r e p r e s e n t a t i v e s o f the a g r i c u l t u r a l i n d u s t r y through i t s trade a s s o c i a t i o n , t h e N a t i o n a l A g r i c u l t u r a l Chemicals A s s o c i a t i o n , w i t h r e p r e s e n t a t i v e s o f t h e US Department o f A g r i c u l t u r e , and w i t h academia i n w r i t i n g a document e n t i t l e d t h e "Safe Use o f P e s t i c i d e s D u r i n g M i x i n g / L o a d i n g and A p p l i c a t i o n . " T h i s document w i l l be a v a i l a b l e t o p e s t i c i d e u s e r s a s a pamphlet i n the n e a r f u t u r e . I t i s i n t e n d e d t o i n c r e a s e t h e i r awareness o f t h e p o t e n t i a l h a z a r d s o f p e s t i c i d e s and t h e k i n d s o f p r o t e c t i v e c l o t h i n g and equipment t h a t s h o u l d be worn t o m i n i m i z e e x p o s u r e . I n a d d i t i o n , t h e pamphlet d i s c u s s e s p r o p e r t i e s o f c h e m i c a l s , t y p e s o f f o r m u l a t i o n s , c l e a n i n g , s t o r a g e , maintenance o f p e r s o n a l p r o t e c t i v e equipment, and c l o s e s w i t h a s e c t i o n o n p e r s o n a l hygiene. R e s e a r c h Needs Our assessment a l s o i n d i c a t e s t h a t , t o d a t e , t o t a l e l i m i n a t i o n o f exposure c a n n o t be a c c o m p l i s h e d b y t h e w e a r i n g o f p r o t e c t i v e equipment (15, 16, 1 7 ) . I f t h e Agency i s t o s a t i s f a c t o r i l y d e v e l o p performance s t a n d a r d s o n p r o t e c t i v e c l o t h i n g m a t e r i a l s , e x t e n s i v e r e s e a r c h i s needed i n s e v e r a l a r e a s : 1) L a b o r a t o r y e v a l u a t i o n o f t h e p e r m e a b i l i t y and p e n e t r a b i l i t y o f various f a b r i c s by d i f f e r e n t classes o f p e s t i c i d e s and f o r m u l a t i o n t y p e s . S i n c e exposure t o t h e hands seems t o be t h e l o c a t i o n o f g r e a t e s t p o t e n t i a l dermal e x p o s u r e , e s p e c i a l l y d u r i n g m i x i n g / l o a d i n g (15, 17, 1 8 ) , the t e s i n g o f v a r i o u s g l o v e m a t e r i a l s s h o u l d r e c e i v e r a t h e r e x t e n s i v e i n i t i a l a t t e n t i o n . I n a d d i t i o n , these e v a l u a t i o n s c o u l d i n c l u d e "normal" c l o t h i n g m a t e r i a l s s u c h as c o t t o n whether t r e a t e d w i t h r e p e l l e n t f i n i s h e s o r u n t r e a t e d a l o n g w i t h o t h e r c o m m e r c i a l l y a v a i l a b l e non-woven c l o t h i n g m a t e r i a l s such a s Tyvek o r G o r e - t e x . 2) F i e l d t e s t i n g o n t h e e f f i c a c y o f d i f f e r e n t t y p e s o f c l o t h ing m a t e r i a l s i n r e d u c i n g p e s t i c i d e exposure t o a p p l i c a t o r s and m i x e r / l o a d e r s . A p p a r e l such a s c o v e r a l l s , h a t s , s u i t s , a p r o n s , hand and f o o t c o v e r i n g s c o u l d be t e s t e d under a c t u a l a g r i c u l t u r a l use c o n d i t i o n s . 3) The development and s t a n d a r d i z a t i o n o f p r a c t i c a l t e s t methods t o e v a l u a t e p r o t e c t i v e a p p a r e l . Two methods r e c e n t l y d e v e l o p e d o f f e r promise i n t h e e v a l u a t i o n o f t h e performance o f p r o t e c t i v e c l o t h i n g : a) ASTM P e r m e a t i o n C e l l T e s t Method ( 1 9 ) . T h i s method d e v e l o p e d b y t h e American S o c i e t y f o r T e s t i n g and M a t e r i a l s (ASTM) u t i l i z e s a t e s t c e l l w h i c h i s a d u a l chambered g l a s s c e l l a p p r o x i m a t e l y 57 mm i n w i d t h . A p i e c e o f t h e m a t e r i a l t o be t e s t e d i s a t t a c h e d between t h e two chambers. The c h e m i c a l i s a d m i t t e d i n t o t h e c h a l l e n g e chamber where i t undergoes d i f f u s i o n / d e s o r p t i o n i n t h e m a t e r i a l a n d , t h r o u g h a c o l l e c t i o n medium, i s drawn o u t o f the o t h e r s i d e . I t i s t h e n p a s s e d t h r o u g h a sample a n a l y z e r such a s a g a s chromatograph w h i c h measures t h e

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b r e a k t h r o u g h time o f t h e c h e m i c a l . The t e s t c e l l i s now used f o r l i q u i d m a t e r i a l s and w i l l be m o d i f i e d f o r use w i t h v a p o r s . T h i s s t a n d a r d ASIM method f o r permeation t e s t i n g can be used t o determine b r e a k t h r o u g h t i m e s f o r p e s t i c i d e s through v a r i o u s c l o t h i n g o r g l o v e m a t e r i a l s . I t r e p r e s e n t s , however, a w o r s t c a s e s c e n a r i o s i n c e i t i s a c o n t i n u o u s l i q u i d / f a b r i c i n t e r p h a s e , p o s s i b l y analogous t o s p i l l s o r s p l a s h e s on c l o t h i n g . I t p r o b a b l y would p r o v i d e a v e r y good benchmark system f o r t e s t i n g p r o t e c t i v e c l o t h i n g m a t e r i a l s . ASTM a l s o has subcommittees on d e v e l o p i n g a p e n e t r a t i o n t e s t method f o r s o l i d s and on t h e c l a s s i f i c a t i o n of protective c l o t h i n g , b) DeJonge P e r m e a t i o n T e s t Method ( 2 0 ) . VJhen f i r s t d e v e l oped, t h i s t e s t method used an e n c l o s e d hood o v e r a v a r i a b l e speed conveyor b e l t where f a b r i c and gauze were l a y e r e d and a t t a c h e d t o wooden frames. The f a b r i c was t h e n passed u n d e r a n o z z l e w h i c h s p r a y s t h e m a t e r i a l and t h e gauze was l a t e r a n a l y z e d f o r c h e m i c a l r e s i d u e s . T h i s method i s c l o s e r t o s i m u l a t i n g exposure under a c t u a l u s e c o n d i t i o n s , and i s c u r r e n t l y b e i n g m o d i f i e d . 4

) The e f f e c t s o f d e c o n t a m i n a t i o n p r o c e d u r e s , such as l a u n d e r i n g , on p e s t i c i d e r e t e n t i o n and t h e p r o t e c t i v e c a p a b i l i t y o f v a r i o u s f a b r i c s need t o be d e t e r m i n e d . 5) The e f f e c t s o f c l o t h i n g d e s i g n , f o r example, seam l e a k a g e , on p r o t e c t i v e c a p a b i l i t y need t o be d e t e r m i n e d . 6) The e f f e c t s o f m a t e r i a l d u r a b i l i t y and d e g r a d a t i o n / w e a r on t h e e f f i c a c y o f p r o t e c t i v e c l o t h i n g need t o be investigated. 7) A system f o r m a i n t a i n i n g , u p d a t i n g , and d i s s e m i n a t i n g s t a t e o f - t h e - a r t i n f o r m a t i o n f o r p e s t i c i d e u s e r s needs t o be d e v e l o p e d so t h a t an i n c r e a s e d h a z a r d awareness by more knowledgeable workers r e s u l t s i n g r e a t e r v o l u n t a r y acceptability of protective clothing. C u r r e n t l y , t h e Agency has d i r e c t e d i t s e f f o r t s i n t h e f o l l o w i n g a r e a s o f r e s e a r c h on c h e m i c a l p r o t e c t i v e c l o t h i n g : 1) The e v a l u a t i o n o f dermal exposure t o a p p l i c a t o r s by u s i n g f l u o r e s c e n t t r a c e r s i n t h e s p r a y tank t o m o n i t o r t h e type and e x t e n t o f worker exposure. T h i s work i s b e i n g conducted a t t h e U n i v e r s i t y o f C a l i f o r n i a - B e r k e l e y under R i c h a r d Fenske and Thomas L e f f i n g w e l l . A s o p h i s t i c a t e d c c m p u t e r v i d e o p r o c e s s i n g system i s b e i n g t e s t e d t o q u a n t i f y p e s t i c i d e exposure t o garments a s w e l l as t h e d e t e r m i n a t i o n of t h e e x t e n t of p e s t i c i d e r e s i d u e s p e n e t r a t i n g t h e c l o t h i n g to the s k i n . 2) A t t h e U n i v e r s i t y o f F l o r i d a , I n s t i t u t e o f Food and A g r i c u l t u r a l S c i e n c e s , A g r i c u l t u r a l R e s e a r c h and E d u c a t i o n C e n t e r i n Lake A l f r e d , F l o r i d a , H e r b e r t N. N i g g i s c o n d u c t i n g r e s e a r c h on t h e t h e e f f i c a c y o f p r o t e c t i v e clothing w h i l e spraying d i c o f o l (Kelthane ) i n c i t r u s g r o v e s . I n a d d i t i o n Dr. N i g g w i l l be i n v e s t i g a t i n g t h e r m a l c o m f o r t of t h e p r o t e c t i v e c l o t h i n g by d i r e c t l y measuring

400

DERMAL EXPOSURE RELATED TO PESTICIDE USE

t e m p e r a t u r e s b o t h on t h e o u t s i d e o f t h e garment worn and on t h e w o r k e r s ' s k i n u s i n g s m a l l t h e r m i s t o r probes. The p e n e t r a b i l i t y o f garment m a t e r i a l s by d i f f e r e n t c l a s s e s o f p e s t i c i d e s and f o r m u l a t i o n t y p e s i s b e i n g i n v e s t i g a t e d i n t h e l a b o r a t o r y b y J a c q u e l y n O r l a n d o DeJonge, Head o f t h e Department o f T e x t i l e s , M e r c h a n d i s i n g and D e s i g n , C o l l e g e o f Home Economics a t t h e U n i v e r s i t y o f Tennessee i n Knoxville. Dr. DeJonge w i l l be s c r e e n i n g d i f f e r e n t garment m a t e r i a l s f o r Dr. Nigg's f i e l d s t u d i e s i n a contained spray apparatus t o s i m u l a t e some n o z z l e t y p e s and spray p r e s s u r e s used i n the f i e l d . U s i n g t h e ASTM p e r m e a t i o n c e l l , t h e O i l and Hazardous M a t e r i a l s S p i l l s Branch o f t h e O f f i c e o f E n v i r o n m e n t a l E n g i n e e r i n g and Technology, O f f i c e o f R e s e a r c h and Development, US EPA w i l l i n i t i a l l y t e s t v a r i o u s g l o v e m a t e r i a l s i n c l u d i n g v i t o n , n a t u r a l rubber, b u t y l rubber, and n i t r i l e r u b b e r a g a i n s t organophosphorous p e s t i c i d e s c u r r e n t l y i n use. Development o f P r o t e c t i v e C l o t h i n g Recommendations Our g o a l i s t o d e v e l o p recanmendations t h a t a r e c o n s i s t e n t w i t h the t o x i c i t y o f t h e chemicals being used. V i i i l e there has been an i n c r e a s e d r e c o g n i t i o n of t h e l i m i t a t i o n s of p r o t e c t i v e c l o t h i n g , t h e r e has a l s o been a n i n c r e a s e d awareness o f t h e h a z a r d s o f exposure t o p o t e n t i a l l y t o x i c p e s t i c i d e s w i t h o u t adequate o r a p p r o p r i a t e p r o t e c t i o n . Our aims a r e t o i d e n t i f y p r o t e c t i v e c l o t h i n g t h a t t h e p e s t i c i d e u s e r , t h e p e s t i c i d e r e g i s t r a n t , and t h e p e s t i c i d e r e g u l a t o r would f i n d e f f e c t i v e and a c c e p t a b l e and t o recommend p r o t e c t i v e c l o t h i n g and equipment on t h e p e s t i c i d e l a b e l where a p p r o p r i a t e t o p r o t e c t a g a i n s t any u n r e a s o n a b l e r i s k t o man. P r o t e c t i v e c l o t h i n g l a b e l i n g recanmendations a r e made n o t o n l y to protect the p e s t i c i d e user against acutely t o x i c materials but a l s o t o p r o t e c t a g a i n s t p o t e n t i a l c h r o n i c hazards. The t o x i c o l o g i c a l o r p r e c a u t i o n a r y s t a t e m e n t m a t r i x , c o n s i s t i n g o f prepared l a b e l s t a t e m e n t s based o n t h e f o u r c a t e g o r i e s o f t o x i c i t y l e v e l s a s d e t e r m i n e d by a c u t e l a b o r a t o r y a n i m a l s t u d i e s (CFR-40, §162.10), p r o v i d e s g u i d a n c e f o r p r o t e c t i v e c l o t h i n g l a b e l i n g recommendations. The c a t e g o r i e s i n t h e m a t r i x t o w h i c h t h e Working Group i s p a y i n g p a r t i c u l a r a t t e n t i o n a r e C a t e g o r i e s I and I I f o r A c u t e Dermal T o x i c i t y (dermal LD50 C a t e g o r y I : _< 200 mg/kg and C a t e g o r y I I : 200 - 2000 mg/kg). The o n l y d i f f e r e n c e between C a t e g o r y I and I I l a b e l s t a t e m e n t s a r e t h e words, " F a t a l i f absorbed t h r o u g h s k i n . . . " r a t h e r t h a n "May be f a t a l i f absorbed through s k i n . . . " The f o l l o w i n g appears a s a p r e c a u t i o n a r y s t a t e m e n t f o r c h e m i c a l s i n b o t h c a t e g o r i e s : "Wear p r o t e c t i v e c l o t h i n g and r u b b e r g l o v e s . . .Remove c o n t a m i n a t e d c l o t h i n g a n d wash b e f o r e r e u s e . " Day t o day e v a l u a t i o n of p o t e n t i a l p e s t i c i d e hazards through t h e v a r i o u s Agency r e g i s t r a t i o n r e v i e w p r o c e s s e s c l e a r l y i n d i c a t e s the need f o r d e v e l o p i n g i n f o r m a t i o n o n p e r s o n a l p r o t e c t i v e equipment. When d e a l i n g w i t h C a t e g o r y I and I I p e s t i c i d e s , l o n g s l e e v e d s h i r t s and long legged p a n t s may n o t p r o v i d e adequate p r o t e c t i o n from e x p o s u r e . I n a d d i t i o n , recommending t h e use o f

28.

MORASKI AND NIELSEN

Protective

Clothing

401

i m p e r m é a b l e c l o t h i n g t h a t has not been t e s t e d f o r i t s c h e m i c a l r e s i s t a n c e i n s t a n d a r d i z e d l a b o r a t o r y a n d / o r f i e l d t r i a l s may n o t r e s u l t i n the l e v e l o f p r o t e c t i o n s o u g h t . Making the proper p r o t e c t i v e c l o t h i n g recanmendation depends not o n l y o n t h e t o x i c i t y o f t h e p e s t i c i d e but on t h e p h y s i c a l - c h e m i c a l i n t e r a c t i o n o f t h e p r o t e c t i v e c l o t h i n g m a t e r i a l and the p e s t i c i d e f o r m u l a t i o n as w e l l . T e s t i n g p r o t e c t i v e c l o t h i n g m a t e r i a l s u s i n g the p r o c e d u r e s d e s c r i b e d i n t h i s paper w i l l a l l o w s p e c i f i c p r o t e c t i v e c l o t h i n g recommenda­ t i o n s t o be made f o r s p e c i f i c p e s t i c i d e u s e s i t u a t i o n s . EPA i s c u r r e n t l y a d d r e s s i n g p r o t e c t i v e c l o t h i n g r e q u i r e m e n t s as they r e l a t e t o farmworker s a f e t y under 40 CFR § 1 7 0 - W o r k e r P r o t e c t i o n S t a n d a r d s for A g r i c u l t u r a l P e s t i c i d e s . P r o t e c t i v e c l o t h i n g requirements, as a regulatory o p t i o n , w i l l become more and more i m p o r t a n t n o t o n l y when d e a l i n g w i t h a c u t e l y t o x i c p e s t i c i d e s but a l s o f o r d e a l i n g w i t h p e s t i c i d e s i d e n t i f i e d as p o t e n t i a l l y causing chronic t o x i c effects. There i s a need n o t o n l y t o d e v e l o p a p p r o p r i a t e performance s t a n d a r d s and t o r e f l e c t t h e s e s t a n d a r d s on l a b e l s , but a l s o t o e f f e c t i v e l y communicate t h e s e developments t o those who use o r a r e exposed t o p e s t i c i d e s . E d u c a t i o n a l programs t h a t s t r e s s the r e l a t i o n s h i p between t o x i c i t y c a t e g o r y o f the p e s t i c i d e and the p r o t e c t i v e c l o t h i n g recxmmendation are suggested. W i t h t h i s renewed emphasis i n w o r k i n g more s a f e l y w i t h p e s t i c i d e s , i t i s hoped t h a t the v o l u n t a r y use o f p r o t e c t i v e c l o t h i n g w i l l become a r e a l i t y . Our o v e r a l l o p i n i o n i s t h a t a w e l l c o o r d i n a t e d e f f o r t i s needed t o e v e n t u a l l y r e s o l v e the p e r t i n e n t i s s u e s . We urge s c i e n t i s t s o r o r g a n i z a t i o n s t h a t have l a b o r a t o r y o r f i e l d performance d a t a on p e s t i c i d e s and p e r s o n a l p r o t e c t i v e equipment t o s h a r e t h a t information w i t h us. N o n t e c h n i c a l Summary P r o t e c t i v e c l o t h i n g p r o v i d e s the most i m p o r t a n t means f o r m i n i m i z i n g exposure t o p e s t i c i d e s d u r i n g m i x i n g / l o a d i n g , a p p l i c a t i o n , and o t h e r p e s t i c i d e o p e r a t i o n s . However, f u n c t i o n a l l i m i t a t i o n s , t h e r m a l d i s c o m f o r t and c o s t a r e among t h e reasons p e s t i c i d e u s e r s may n o t wear t h e i r p r o t e c t i v e o u t f i t s . The US EPA i s e v a l u a t i n g c u r r e n t p r o t e c t i v e c l o t h i n g t e c h n o l o g y f o r the purpose o f d e v e l o p i n g performance s t a n d a r d s . These s t a n d a r d s w i l l be r e f l e c t e d i n t h e p r e c a u t i o n a r y s t a t e m e n t s found on p e s t i c i d e c o n t a i n e r l a b e l s w h i c h a r e made t o p r o t e c t t h e p e s t i c i d e u s e r a g a i n s t not o n l y a c u t e l y t o x i c m a t e r i a l s but a l s o a g a i n s t c h r o n i c h a z a r d s . C u r r e n t and f u t u r e r e s e a r c h needs a r e d i s c u s s e d .

Literature Cited 1. "Your Guide to the Environmental Protection Agency," U.S. Environmental Protection Agency. ΟΡΑ 138/0, 1980. 2. Durham, W. F.; Wolfe, J. H.; Elliot, J . W. Arch. Environ. Health 1972, 24, 381-387. 3. Maddy, K. T.; Smith, C. R.; Kilgore, S. L. "Occupational Ill­ nesses and Injuries of Mixers and Loaders of Pesticides in California as Reported by Physicians in 1980," California Depart­ ment of Food and Agriculture, Report No. HS955, 1981.

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DERMAL EXPOSURE RELATED TO PESTICIDE USE

4. Maibach, H. I.; Feldman, R. J.; Milby T. H.; Serat, W. F. Arch. Environ. Health 1971, 23, 208-211. 5. Serat, W. F.; Feldman R. J.; Maibach, H. I. Natn. Pest Control Operator NEWS 1973, October. 6. Feldman, R. J.; Maibach, H. I.; Toxic. Appl. Pharmacol. 1974, 28, 126-132. 7. Wolfe, H. R. Weeds, Trees and Turf 1973, 12(4), 12. 8. Wolfe, H. R.; Durham, W. F.; Armstrong, J. F. Arch. Environ. Health 1967, 14, 622-633. 9. Wolfe, H. R.; Armstrong, J. F.; Staiff, D. C.; Comer, S. W. Arch. Environ. Health 1967, 25, 29-31. 10. Bohmont, B. L. "The New Pesticide User's Guide," Reston Publishing Company, Inc.: Reston, VA, 1983; Chap. 8. 11. Jacobs, W. W. "Closed Systems for Mixing and Loading," at the Determination and Assessment of Pesticide Exposure Workshop, USDA, NJAES, US EPA; Hershey, PA, 1980. 12. Russell, L. S. "Catalog of Protective Clothing/Safety Equipment for the Pesticide Applicator," U.S. Environmental Protection Agency, 1981. 13. Bodden, M.; Cioffi, J.; Fong, V.; McLaughlin, M.; Russell, S. "Summary of Research on Protective Materials for Agricultural Pesticide Uses," U.S. Environmental Protection Agency, 1983. 14. Schwope, A. D.; Costas, P. P.; Jackson, J. O.; Weitzraan, D. J.; "Guidelines for the Selection of Chemical Protective Clothing," Volumes I and I I , U.S. Environmental Protection Agency, 1983. 15. Dubelman, S.; Lauer, R.; Arras, D. D.; Adams, S. A. J. Agric. Food Chem., 1982, 30, 528-532. 16. Sheets, T. J. "Exposure of Hand Harvesters to MH in the Field, Final Report," 1980, Agricultural Research Service, North Carolina State University, Raleigh, NC. 17. "Applicator and Mixer/Loader Exposure to Pesticides During Ground Boom Spraying Operations," Draft Report, 1981, U.S. Environmental Protection Agency. 18. Maddy, K. T.; Winter, C.; Cepello, S.; Fredrickson, A. S. "Monitoring of Potential Occupational Exposure of Mixer/Loaders, Pilots, and Flaggers During Application of Phosdrin (Mevinphos) in Imperial County in 1981," California Department of Food and Agriculture, Report No. HS-899 Rev., 1982. 19. "Standard Test Method for Resistance of Protective Clothing Materials to Permeation by Hazardous Liquid Chemicals: Designation F 739-81," American Society for Testing and Materials, Annual Book of ASTM Standards, 1981. 20. Orlando, J.; Branson, D.; Ayers, G.; Leavitt, R. J. Environ. Sci. Health, 1981, Β 16(5), 617-628. RECEIVED September 24, 1984