An Environmentalist's View of Toxicology and Pesticide Regulation

29 An Environmentalist's View of Toxicology and Pesticide Regulation JACQUELINE M. WARREN Downloaded by NATL UNIV OF SINGAPORE on May 5, 2018 | https://pubs.acs.org Publication Date: August 10, 1981 | doi: 10.1021/bk-1981-0160.ch029

Environmental Defense Fund, 475 Park Avenue South, New York, NY

10016

The Environmental Defense Fund has been actively involved in the pesticide regulatory process for more than 12 years. Beginning in 1967, EDF lawyers and scientists have participated in administrative and judicial proceedings to suspend or cancel DDT, mirex, aldrin, dieldrin, chlordane, heptachlor and, currently, the herbicide 2,4,5-T. Along with pesticide manufacturers and user groups, EDF comments extensively on the development of the pesticide registration guidelines under §3 of FIFRA. EDF has also submitted comments and data in proceedings relating to a wide variety of regulatory and administrative actions proposed by the EPA. EDF's concerns about pesticide use have focused primarily upon involuntary human exposure to hazardous compounds, especially through the food chain, and upon detrimental effects of pesticide use on non-target species. Since pesticides are poisons by definition, and are specifically designed to kill, EDF has sought comprehensive testing and assessment of the health and environmental effects of pesticides before they are widely used. This preventive or "test-first" approach was incorporated into FIFRA in 1972, when Congress gave EPA the authority to develop hazard evaluation guidelines for the registration of pesticides. The basic regulatory standard, which requires that pesticides be shown to pose no unreasonable adverse effects on the environment, places the burden of establishing that a pesticide may be safely used directly upon the registrant. Since a l l pesticides are likely to be hazardous unless properly used, an applicant for registration must not only provide the EPA with comprehensive evidence of the potential adverse health and environmental effects of a particular compound, but must also demonstrate that the risks outweigh the benefits when the pesticide is properly used. The burden that FIFRA imposes upon registrants i s a d i f f i cult one to meet, but the cost to society of a "use-first-testlater" approach has been firmly rejected by Congress and the courts.

0097-6156/81/0160-0473$05.00/0 © 1981 American Chemical Society Bandal et al.; The Pesticide Chemist and Modern Toxicology ACS Symposium Series; American Chemical Society: Washington, DC, 1981.

THE

Downloaded by NATL UNIV OF SINGAPORE on May 5, 2018 | https://pubs.acs.org Publication Date: August 10, 1981 | doi: 10.1021/bk-1981-0160.ch029

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In the face of extensive evidence o f widespread contaminat i o n of the environment, the food c h a i n , and human t i s s u e s with p e s t i c i d e r e s i d u e s , EPA has acted to remove a small number o f p e r s i s t e n t c a r c i n o g e n i c or otherwise h i g h l y toxic p e s t i c i d e s from the marketplace. The nature and extent o f the exposure r e s u l t i n g from the use o f some o f those compounds was w e l l i l l u s t r a t e d i n the proceedings f o r suspension and c a n c e l l a t i o n o f a l d r i n , d i e l d r i n , chlordane and heptachlor. For example, the FDA's annual Market Basket Surveys showed c o n s i s t e n t l y high and i n c r e a s ing residues of d i e l d r i n and heptachlor epoxide i n meat, f i s h , p o u l t r y and d a i r y products. In a d d i t i o n , the EPA's Human Monitoring Survey, which analyzes human adipose t i s s u e samples from s u r g i c a l procedures and a u t o p s i e s , from 1970 to 1972 found measurable d i e l d r i n residues i n 9 6 . 5 , 9 9 - 5 and 98.2% o f the samples tested. S i m i l a r l y , between 1971 and 197^ the Survey found heptachlor epoxide and oxychlordane r e s i d u e s , both metab o l i t e s of heptachlor and chlordane, i n more than 90% of the t i s s u e samples analyzed (Table I ) . The average residues o f heptachlor epoxide and oxychlordane ranged from 0 . 0 8 - 0 . 0 9 ppm and 10-12 ppm, r e s p e c t i v e l y . Table I Percentages o f P o s i t i v e Samples Found from 1971-197** Year

Heptachlor Epoxide

1971 1972 1973 197^

96.2 90.3 97.7 96.3

Oxychlordane 93.3 92.3 98.3 98.6

Faced with evidence o f the c a r c i n o g e n i c i t y i n rodents o f the p e s t i c i d e s i n question, EPA c a n c e l l e d t h e i r r e g i s t r a t i o n s f o r most uses. Those a c t i o n s have been a f f i r m e d i n a s e r i e s o f c o u r t d e c i s i o n s upholding the Agency's preventive approach to the r e g u l a t i o n of carcinogens. The b a s i c p r i n c i p l e i s that " i f r e g u l a t i o n were withheld u n t i l the danger was demonstrated conc l u s i v e l y , untold i n j u r y to p u b l i c health could r e s u l t . " EDF v. EPA, 598 F. 2d 62 (D.C. C i r . 1 9 7 8 ) . The same s t r i n g e n t r e g i s t r a t i o n standards a p p l i e d to the c h l o r i n a t e d hydrocarbon p e s t i c i d e s mentioned above, and that a l l new p e s t i c i d e s must meet, are slowly being a p p l i e d to 1500 e x i s t i n g a c t i v e p e s t i c i d e i n g r e d i e n t s , the v a r i o u s formulations of which comprise the approximately ^ 5 , 0 0 0 p e s t i c i d e products c u r r e n t l y r e g i s t e r e d . Over the next s e v e r a l years, a l l of these r e g i s t r a t i o n s must be reviewed by EPA and d e c i s i o n s made e i t h e r to continue or to cancel them. The Agency's review process involves evaluation o f the t o x i c o l o g y data supporting the r e g i s t r a t i o n s as w e l l as c o n s i d e r a t i o n of the b e n e f i t s provided by use of the p e s t i c i d e s .

Bandal et al.; The Pesticide Chemist and Modern Toxicology ACS Symposium Series; American Chemical Society: Washington, DC, 1981.


29.

WARREN

Environmentalist's

View of

Toxicology

475

The unreasonable adverse e f f e c t s standard set f o r t h i n FIFRA r e q u i r e s the EPA to conduct a r i s k - b e n e f i t b a l a n c i n g i n which the economic, s o c i a l , and environmental c o s t s and b e n e f i t s o f the use of each p e s t i c i d e are taken into account. To perform the s t a t u t o r i l y mandated b a l a n c i n g , EPA must have the most complete knowledge p o s s i b l e about the p o t e n t i a l r i s k s posed by use o f a p e s t i c i d e , as w e l l as the r e l a t i v e c o s t s , a v a i l a b i l i t y and e f f e c t i v e n e s s o f s u b s t i t u t e compounds. The importance o f accurate t o x i c o l o g i c a l information f o r the performance o f the r i s k - b e n e f i t b a l a n c i n g cannot be over-emphasized. For t h i s reason, EPA has not only s p e c i f i e d what data must be provided to support a p e s t i c i d e r e g i s t r a t i o n , but has a l s o r e c e n t l y proposed Good Laboratory P r a c t i c e G u i d e l i n e s f o r Toxicology T e s t i n g \ L ' i n an e f f o r t to assure the i n t e g r i t y o f the data. There are good reasons supporting EPA s d e c i s i o n to propose Good Laboratory P r a c t i c e G u i d e l i n e s . Beginning i n 1 9 7 5 , there have been numerous d i s c l o s u r e s o f " i r r e g u l a r i t i e s " , both d e l i b erate and i n a d v e r t e n t , i n data submitted to FDA to support v a r i o u s regulated food and drug products, and to EPA to support p e s t i c i d e r e g i s t r a t i o n s and food t o l e r a n c e s . Such g u i d e l i n e s are long overdue. Indeed, s e v e r a l Congressional hearings and subsequent r e g u l a t o r y agency i n v e s t i g a t i o n s document d r a s t i c s h o r t comings i n the i n t e g r i t y o f many t o x i c i t y s t u d i e s and r e p o r t s submitted to FDA and EPA. "Unacceptable l a b o r a t o r y p r a c t i c e s " have been found a t several c o n t r a c t l a b o r a t o r i e s , and a t drug and p e s t i c i d e manufacturing p l a n t s , that r a i s e very s e r i o u s questions about the v a l i d i t y o f the data generated there. According to the EPA, 1

"The unacceptable p r a c t i c e s noted included s e l e c t i v e r e p o r t i n g and underreporting o f t e s t r e s u l t s , l a c k o f adherence to s p e c i f i e d p r o t o c o l s , inadequate q u a l i f i c a t i o n and s u p e r v i s i o n o f personnel, poor animal care procedures, poor record-keeping techniques and the general f a i l u r e o f sponsors to monitor s t u d i e s " ' — ' * In a d d i t i o n to these d e f i c i e n c i e s , the data have a l s o o f t e n been so poorly tabulated and summarized that a c o n c l u s i o n as to c a r c i n o g e n i c i t y could not be made. As a r e s u l t o f the problems that were created by these and other methodological shortcomings, such as an inadequate number o f animals, f a i l u r e to r e p o r t f i n d ings on a l l t i s s u e s s t u d i e d , and l a c k o f data on s t a t i s t i c a l d i f f e r e n c e s i n e f f e c t s on treated as compared with c o n t r o l animals, a s i g n i f i c a n t p o r t i o n o f the data supporting p e s t i c i d e t o l e r a n c e s and r e g i s t r a t i o n s has been d i s c r e d i t e d as u n r e l i a b l e . In testimony before a Senate committee i n 1 9 7 6 , EPA Deputy A d m i n i s t r a t o r John Quarles admitted that h i s Agency's i n v e s t i g a t i o n showed that " s e r i o u s problems" might e x i s t with the t o x i cology data supporting p e s t i c i d e r e g i s t r a t i o n s . One example o f such "problems" was the d e l i b e r a t e withholding o f v a l i d r e s u l t s



476

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because a l a b o r a t o r y might be so dependent upon a p e s t i c i d e producer f o r c o n t r a c t work that i t s independent s c i e n t i f i c judgment could be imparled by the c l o s e economic r e l a t i o n s h i p . Quarles a l s o suggested that a l a b o r a t o r y might i n t e n t i o n a l l y misrepresent r e s u l t s at the request o f the manufacturer. A vivid illustration of such a s i t u a t i o n was the 1978 f e d e r a l grand j u r y indictment i n Chicago of six corporate o f f i c e r s o f V e l s i c o l Chemical Corporat i o n f o r a l l e g e d l y withholding s t u d i e s i n d i c a t i n g the c a r c i n o g e n i c i t y of heptachlor and chlordane from the Environmental P r o t e c t i o n Agency. Other l a b o r a t o r i e s ' procedures have a l s o been found to be so questionable by a j o i n t EPA-FDA a u d i t program that some o f the audited f a c i l i t i e s have been r e f e r r e d to the Department o f Just i c e f o r p o s s i b l e prosecution. Thus, p u b l i c confidence i n Agency r e g u l a t o r y d e c i s i o n s based upon t o x i c o l o g y data generated and submitted by drug manufacturers and p e s t i c i d e r e g i s t r a n t s , o f t e n the same companies, has been s e r i o u s l y undermined. The p u b l i c a tion and implementation of Good Laboratory P r a c t i c e requirements by EPA and FDA should help to a l l e v i a t e some o f the p u b l i c ' s misgivings about the v a l i d i t y o f data generated by the p e s t i c i d e and drug i n d u s t r y , but i t i s c l e a r that r i g o r o u s enforcement o f these requirements w i l l be necessary i f the r e g u l a t o r y process i s to f u n c t i o n e f f e c t i v e l y to p r o t e c t p u b l i c h e a l t h and the environment. Perhaps the major area o f disagreement between environment a l i s t s and the p e s t i c i d e i n d u s t r y i s the question o f how much evidence of r i s k i s necessary to j u s t i f y r e g u l a t o r y a c t i o n . I t i s not merely a question o f b a l a n c i n g r i s k s and b e n e f i t s , but o f d e f i n i n g r i s k s i n the f i r s t p l a c e . Much o f the p u b l i c debate surrounding the r e g u l a t i o n o f c a r c i n o g e n i c p e s t i c i d e s , and o f a l l environmental carcinogens, f o r that matter, has focused upon the h i s t o p a t h o l o g i c a l d e f i n i t i o n of what i s a carcinogen, the extrapol a t i o n o f animal c a r c i n o g e n i c i t y evidence to humans, and the q u a n t i f i c a t i o n o f cancer r i s k i n humans. The science involved i n these determinations i s so imprecise and so subject to v a r y i n g i n t e r p r e t a t i o n s that d e f i n i t i v e c o n c l u s i o n s cannot be drawn. The debate i s f u r t h e r complicated by the background o f m i s t r u s t and s u s p i c i o n about the q u a l i t y o f i n d u s t r y - s u p p l i e d t o x i c i t y data, that r e s u l t e d from the aforementioned d i s c l o s u r e s o f improprieties i n laboratory practice. The task o f balancing r i s k s and b e n e f i t s i s extremely d i f f i c u l t when there i s no agreement about what i s on e i t h e r side o f the equation. The evidence o f p o t e n t i a l hazard to humans i s very o f t e n h y p o t h e t i c a l or suggestive r a t h e r than c o n c l u s i v e . Often the r e g u l a t o r y agencies are d e a l i n g with reasonable medical theory or e p i d e m i o l o g i c a l evidence suggesting, but not proving, a s s o c i a t i o n s between exposure to p a r t i c u l a r chemicals and increased incidence o f disease. At the same time, the b e n e f i t s o f continued use of the compound i n question, be i t a p e s t i c i d e , drug or i n d u s t r i a l chemical, are u s u a l l y claimed by the a f f e c t e d


29.

WARREN

Environmentalist's

View of

Toxicology

477

i n d u s t r y and users to be very extensive. Government o f f i c i a l s charged with p r o t e c t i n g p u b l i c h e a l t h and the environment must t h e r e f o r e make d e c i s i o n s which w i l l have measurable economic impacts i n order to prevent p o t e n t i a l harm, the magnitude o f which cannot be r e a d i l y a s c e r t a i n e d . In such s i t u a t i o n s , the manufacturer and users o f a p e s t i c i d e , f o r example, argue f o r continued use, while e n v i r o n m e n t a l i s t s , consumers and p u b l i c h e a l t h o f f i c i a l s s t r o n g l y urge a preventive approach. Based on past experience, Agency d e c i s i o n s to take prot e c t i v e a c t i o n w i l l g e n e r a l l y be upheld by the c o u r t s . In a long l i n e o f cases l i b e r a l l y c o n s t r u i n g the A g e n c i e s a u t h o r i t y to a c t to p r o t e c t p u b l i c h e a l t h , the c o u r t s have recognized that the s o c i a l cost of a wrong d e c i s i o n i s f a r l e s s where only the benef i t o f use o f a product has been foregone; i r r e p a r a b l e i n j u r y to h e a l t h or the environment cannot be so r e a d i l y recouped. These are some of the concerns that have d i r e c t e d EDF* s involvement i n the p e s t i c i d e r e g u l a t o r y process. EPA faces an immense task i n reviewing the t o x i c o l o g i c a l support f o r tens o f thousands o f p e s t i c i d e r e g i s t r a t i o n s , which c o n s i s t s o f more than a m i l l i o n s t u d i e s . Only time and c o n s c i e n t i o u s e f f o r t w i l l enable the agency to complete the j o b . To ensure that past abuses w i l l not occur i n the f u t u r e , however, the generation o f t o x i c o l o g i c a l data should be guided by c a r e f u l compliance with the Good Laboratory P r a c t i c e standards c u r r e n t l y being developed by EPA f o r the t e s t i n g of p e s t i c i d e s . S c i e n t i s t s have a r e s p o n s i b i l i t y to t h e i r p r o f e s s i o n and to f u t u r e generations to f a c i l i t a t e the o b j e c t i v e and complete e v a l u a t i o n of the p o t e n t i a l h e a l t h and environmental hazards o f p e s t i c i d e s . We are a l l l i v i n g today with the consequences o f the f a i l u r e s o f the past. I t i s time to put i n t o p r a c t i c e the o l d adage that "an ounce o f prevention i s worth a pound o f c u r e . "


1

Literature Cited 1.

Guidelines for Registering Pesticides in the United States; Proposed Good Laboratory Practice Guidelines for Toxicology Testing, 45 Fed. Reg. 26373 (April 8, 1980).

2.

Good Laboratory Practices Standards for Health Effects, 44 Fed. Reg. 27364 (May 9, 1979). [EPA Standards for Testing under §4 of the Toxic Substances Control Act].

RECEIVED March 31,

1981.


An Environmentalist's View of Toxicology and Pesticide Regulation

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