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The Love Canal: Issues and problems
Chemosphere,Vol.12,No.4/5,pp P r i n t e d in Creat B r i t a i n
705--712,1983
THE LOVE CANAL:
Nicholas
0 0 4 5 6535/83/050705-.08503.00/0 © 1 9 8 3 ~ e r g a m o n Press Ltd.
ISSUES AND P R O B L E M S
J. Vianna,
M.D.,
M.S.P.H.
N e w York State D e p a r t m e n t of H e a l t h D i v i s i o n of H e a l t h Risk C o n t r o l Albany, N e w York 12237
The Love Canal has come to s y m b o l i z e the m a n y p r o b l e m s and u n r e s o l v e d s c i e n t i f i c issues r e l a t i n g to the d i s p o s a l of i n d u s t r i a l w a s t e p r o d u c t s in landfills. S i t u a t i o n s of this type are e x c e e d i n g l y c o m p l e x since they d i r e c t l y impact on the social, psychologic, and e c on o m i c w e l l - b e i n g of the involved community. U n d e r l y i n g all of these issues is the f u n d a m e n t a l q u e s t i o n w h e t h e r r e s i d i n g in c l o s e p r o x i m i t y to an i n d u s t r i a l w a s t e s i t e r e p r e s e n t s a h e a l t h h a z a r d for area residents. A clear u n d e r s t a n d i n g of the Love C a n a l p r o b l e m n e c e s s i t a t e s a c h a r a c t e r i z a t i o n of the types of c h e m i c a l s located in the d u m p s i t e and p o s s i b l e paths of migration. T h e s e factors m u s t in turn be i n t e r p r e t e d in light of the t e m p o r a l d e v e l o p m e n t of the area. This r e p o r t will r e v i e w the h i s t o r i c a l d e v e l o p m e n t of the Love Canal area and the c h e m i c a l and e p i d e m i o l o g i c a l e f f o r t s that were i n i t i a t e d by the State of N e w York. M a j o r e m p h a s i s will be p l a c e d on some of the m a j o r s c i e n t i f i c issues e n c o u n t e r e d in each of these i n v e s t i g a t i o n s .
HISTORY
OF THE LOVE C A N A L
The Love Canal is a r e c t a n g u l a r , sixteen-acre, b e l o w - g r o u n d level landfill site located in a r e s i d e n t i a l section of the s o u t h e a s t corner of N i a g a r a City, N e w York (1,2). In the late n i n e t e e n t h century, the site was e x c a v a t e d as part of a p r o p o s e d canal linking the N i a g a r a River and Lake Ontario. The p u r p o s e of the Canal was to p r o d u c e h y d r o e l e c t r i c power for use in a model city. In 1938 the Canal was a p p r o x i m a t e l y 3000 feet long and 100 feet wide and there was no e v i d e n c e of w a s t e disposal. The Love Canal p r o j e c t was a b a n d o n e d and was s u b s e q u e n t l y used for d i s p o s a l of c h e m i c a l w a s t e s (e.g., c h l o r i n a t e d h y d r o c a r b o n residues, p r o c e s s e d sludges, flyash) until about 1953 (1,2). A e r i a l p h o t o g r a p h s of the study area from 1938 show h o u s i n g c o n f i n e d a l m o s t e x c l u s i v e l y to 101st, 102nd, and 103rd Streets in the form of s i n g l e - f a m i l y houses and farms (Figure i). By 1951, there were still no homes on 197th Street, but a few new houses were p r e s e n t on the s o u t h e a s t e r n sections of 99th through 103rd Streets. H o u s i n g c o n s t r u c t i o n p r o c e e d e d t h r o u g h the 1960's and was m o s t l y c o m p l e t e d on 99th Street by 1965, but c o n t i n u e d on 97th Street through 705
706
•I// //.d
;ATMt ~At,
\
Figure 1
707
1973. Presently, the site is c o n t a i n e d w i t h i n the area b o r d e r e d by C o l v i n Avenue, F r o n t i e r A v e n u e and 99th Street (Figure i). S o u t h e r n and n o r t h e r n sections of the o r i g i n a l Love C a n a l are b o r d e r e d by the b a c k y a r d s of s i n g l e - f a m i l y homes on 97th and 99th Streets, w h i l e the m i d d l e section is o c c u p i e d by an e l e m e n t a r y school. By 1972 v i r t u a l l y all houses w h o s e b a c k y a r d s d i r e c t l y abut the Love Canal were completed. An i m p o r t a n t feature for the c o r r e l a t i o n b e t w e e n i l l n e s s e s and c h e m i c a l leachates were the natural d r a i n a g e ways o f f e r i n g p r e f e r e n t i a l routes for the m o v e m e n t of liquids underground. In fact deep d e p r e s s i o n s or swales (Figure i) t r a v e r s e d the area, some i n t e r s e c t i n g the Love C a n a l itself. These swales w e r e shallow, g e n e r a l l y no m o r e than six feet deep, and c o n t a i n e d water p r i m a r i l y d u r i n g the wet season. The m a j o r swale i n t e r s e c t e d the C a n a l ' s n o r t h e r n section and p a s s e d to the east of it along a n o r t h w e s t - s o u t h e a s t line to 103rd Street (Figure i). The p r e c i s e l o c a t i o n of these swales was d e t e r m i n e d from aerial p h o t o g r a p h s taken in 1938, 1951 and 1966, as i n d e p e n d e n t l y i n t e r p r e t e d by the C o r n e l l School of Civil and E n v i r o n m e n t a l Engineering. As the area was developed, the contour and e x t e n t of these swales was s u b s t a n t i a l l y modified. D e v e l o p m e n t of the area b e t w e e n 1951 and 1956 e l i m i n a t e d the m a j o r swale w h i c h i n t e r s e c t e d the Canal as a c o n t i n u o u s c o n d u i t of surface water flow from the Canal to p e r i p h e r a l areas (Figure i). In 1953 Hooker C h e m i c a l C o m p a n y sold the Love Canal to the N i a g a r a Falls Board of Education, and one year later an e l e m e n t a r y school was built on this p r o p e r t y (Figure i).
CHEMICAL
INVESTIGATION
E x t e n s i v e e n v i r o n m e n t a l testing was r e q u i r e d to i d e n t i f y m o s t of the c h e m i c a l c o m p o u n d s p r e s e n t in the Love Canal at the time N e w York State H e a l t h D e p a r t m e n t studies were initiated. T a b l e 1 lists some of the m o r e than 200 c h e m i c a l s thus far i d e n t i f i e d in this w a s t e s i t e (2). Table
1
Some of the more
important
chemicals
identified
Chloroform
Pentachlorobenzene
Carbon
Allyl
tetrachloride
phenols
l.l-dichloroethane
Hexachlorobenzene
1.2-dichloroethane
Tetra,
penta,
hexa
l.l.l-trichloroethane
chlorinated
Trichloroethylene
or p h e n a n t r a c e n e s
Tetrachloroethylene
2,3,7,8-TCDD
Chlorobenzene Dichlorobenzene
at Love Canal
antracenes
and other T C D D s
Hexachlorodibenzodioxin (2 isomers)
Dichlorodibenzodioxin
1,2-dichloropropane
Chlorinated
Chlorotoluene
Trichlorophenols
(2 isomers)
naphthalenes (isomers)
708
Chlorobenzaldeyde Dichlorotoluene
(isomers) (3 isomers)
Dichlorobenzaldeyde Trichlorobenzene
PCBs
(isomers)
Octachlorocyclopentane
(isomers)
(3 isomers)
1,2-dibromoethane Trichlorotoluene
(5 isomers)
Tetrachlorotoluene
(isomers)
Tetrachlorobenzene
(3 isomers)
Benzene Toluene v.s.p.
Xylenes
Benzaldeyde Chlorotoluenes
The first 21 c h e m i c a l s have been i d e n t i f i e d by both the EPA and by the N e w York State H e a l t h Department. The r e m a i n i n g c o m p o u n d were identified by the N.Y. State H e a l t h D e p a r t m e n t Dioxin (2,3,7,8 t e t r a c h l o r o d i b e n z o - p a r a d i o x i n ) was one of the c h e m i c a l s found in the landfill. Its p r e s e n c e was p r o b a b l y due to the fact that the Hooker C h e m i c a l C o m p a n y buried a p p r o x i m a t e l y 200 tons of t r i c h l o r o p h e n o l s in the Love Canal between 1942 and 1953. It is well e s t a b l i s h e d that d i o x i n is a c o n t a m i n a n t b y p r o d u c t formed d u r i n g the m a n u f a c t u r e of t r i c h l o r o p h e n o l s . Several a n a l y s e s have d e m o n s t r a t e d the p r e s e n c e of this c h e m i c a l in soil samples from the landfill, the b a c k y a r d s of nearby homes and the sediment and m a r i n e life of two oceans b o a r d e r i n g the Love Canal neighborhood. To date the highest c o n c e n t r a t i o n of d i o x i n found is a p p r o x i m a t e l y 300 parts per b i l l i o n in a storm sewer a d j o i n i n g the Canal area. This o b s e r v a t i o n is of great p o t e n t i a l importance since a v a i l a b l e evidence suggests that between 1957 and 1960 at least two sewer pipes were laid right through the Canal ten feet b e l o w the surface The gravel bed g e n e r a l l y used around these pipes could provide a p o t e n t i a l conduit for the m i g r a t i o n of certain c h e m i c a l s buried w i t h i n the wastesite. The chemical i n v e s t i g a t i o n s at the Love Canal have raised m a n y u n r e s o l v e d issues. C l e a r l y all of the c h e m i c a l s d e p o s i t e d in the site have not been identified. Of the hundreds of c h e m i c a l s found, w h i c h ones should be m o n i t o r e d and what types of samples should be o b t a i n e d (e.g., air, water, soil)? Special care m u s t be taken in the c o l l e c t i o n of e n v i r o n m e n t a l samples and the issue of specimen h o m o g e n e i t y must o b v i o u s l y be a d d r e s s e d (3). C l e a r l y c e r t a i n c h a r a c t e r i s t i c s of soil can influence chemical analyses. The humic f r a c t i o n in m a n y a g r i c u l t u r a l soils is c o m p o s e d of lipids w h i c h can i m m o b i l i z e f a t - s o l u b l e o r g a n o c h l o r i n e pesticides. C e r t a i n inorganic c h e m i c a l s may p e r c i p i t a t e out in soil water as oxides. D e t a i l e d c o n s i d e r a t i o n m u s t also be g i v e n to the m o d e s d e g r a d a t i o n and half life of c h e m i c a l s s e l e c t e d for
of
709
surveillance. This is an i m p o r t a n t issue p a r t i c u l a r l y w h e n c u r r e n t c h e m i c a l a n a l y s e s are being used to gain some insight into the types of c o m p o u n d s d e p o s i t e d in prior years. F u r t h e r i n v e s t i g a t i o n of the date and r e s i d e n c e times of c h e m i c a l s in d i f f e r e n t types of soil is an i m p o r t a n t p r i o r i t y in future research. Still o t h e r p r o b l e m s became e v i d e n t in the c o u r s e of our investigations. The h u m a n t o x i c i t y of c o m p o u n d s such as tetrachlorodibenzo-p-dioxin (TCDD) has not been fully d e l i n e a t e d and there are m a r k e d v a r i a t i o n s in the s u s c e p t i b i l i t y of d i f f e r e n t animal species to this compound. In c e r t a i n animal m o d e l s TCDD p r o m o t e s c a r c i n o g e n i c i t y . G i v e n the large number of c h e m i c a l s found in the Love C a n a l the p o s s i b i l i t y of synergistic, a d d i t i v e or a n t a g o n i s t i c r e a c t i o n s m u s t be considered. Ideally these issues are e v a l u a t e d in l a b o r a t o r y s e t t i n g s under c o n t r o l l e d c i r c u m s t a n c e s . U n f o r t u n a t e l y it is e x c e e d i n g l y d i f f i c u l t to s i m u l a t e the field c o n d i t i o n s of a c h e m i c a l w a s t e s i t e in a laboratory. Perhaps a partial answer to this d i f f i c u l t y is to c o n d u c t t o x i c o l o g i c studies on the wild animal life i n d i g e n o u s to the area u n d e r investigation. The use of n a t i v e plants in such studies m i g h t be somewhat limited since u p t a k e of m a n y c h e m i c a l c o n t a m i n a n t s m i g h t be only temporary.
HEALTH
INVESTIGATIONS
The f u n d a m e n t a l q u e s t i o n u n d e r l y i n g all toxic w a s t e s i t e s is w h e t h e r they r e p r e s e n t a h e a l t h hazard to man. U n f o r t u n a t e l y this is a m o s t d i f f i c u l t issue to fully address. W i t h o u t some k n o w l e d g e about the c h e m i c a l c o n t e n t s in a wastesite, it is v i r t u a l l y i m p o s s i b l e to c o n d u c t m e a n i n g f u l studies. In s e t t i n g s w h e r e there is no r e c o r d of the c h e m i c a l s deposited, it is e x c e e d i n g l y d i f f i c u l t to d e t e r m i n e what to test for. Even w h e n such d e c i s i o n s are made, the c o n f o u n d i n g i n f l u e n c e of c h e m i c a l s found in h o u s e h o l d and lawn p r o d u c t s (e.g., detergents, fertilizers, pesticides) has to be considered. In addition, m o s t sites d i f f e r with r e g a r d to some i m p o r t a n t v a r i a b l e s including their c h e m i c a l c o n t e n t s and their method(s) of storage, the m o d e of c o n s t r u c t i o n of the site, soil and h y d r o g e o l o g i c a l c h a r a c t e r i s t i c s , routes of p o t e n t i a l m i g r a t i o n that are manmade, and p r o x i m i t y to w a t e r supplies. D e s p i t e these and other m a j o r d i f f i c u l t i e s , the central issue of human h e a l t h m u s t be addressed. C l e a r l y this is the r e s p o n s i b i l i t y of the c l i n i c a l and e p i d e m i o l o g i c d i s c i p l i n e s . H e a l t h risk a s s e s s m e n t e s t i m a t e s based on animal studies, w h i l e p a r t i c u l a r l y useful in s i t u a t i o n s w h e r e there is no h u m a n data, will never fully satisfy the c o n c e r n s of p o t e n t i a l l y e x p o s e d residents. The s e l e c t i o n of h e a l t h end points m u s t d e p e n d to a large extent on the types of c h e m i c a l s p r e s e n t and their e s t a b l i s h e d effects on man. M a n y c o m p o u n d s found in the Love Canal are e s t a b l i s h e d skin i r r i t a n t s (e.g., benzene, b e n z o i c acid, t r i c h l o r o e t h y l e n e and chloroform) (i). O t h e r s such as carbon t e t r a c h l o r i d e can c a u s e toxic h e p a t i t i s (i). Still others (e.g., lindane) can p r o d u c e frank c o n v u l s i o n s if s u f f i c i e n t amounts are ingested
(i)
.
710
Accordingly, these d i s o r d e r s are good "acute end points" to study in this setting. Greater d i f f i c u l t y is e n c o u n t e r e d when one attempts to identify a p p r o p r i a t e d i s e a s e states w h i c h m i g h t be i n d i c a t i v e of "chronic e x p o s u r e to toxic chemicals". The c a r c i n o g e n i c effect of m a n y chemical compounds is well e s t a b l i s h e d in certain o c c u p a t i o n a l settings. In addition, d e a th c e r t i f i c a t e s g e n e r a l l y provide a r e a d i l y a v a i l a b l e m e a n s of m o n i t o r i n g various cancers in specific g e o g r a p h i c areas. These facts suggest that m a l i g n a n t d i s o r d e r s m i g h t r e p r e s e n t end points for e n v i r o n m e n t a l monitoring. This is e s p e c i a l l y true of children, since the s e l e c t i o n of this age g r o u p e s s e n t i a l l y eliminates the influence of o c c u n a t i o n a l factors. But there are some serious l i m i t a t i o n s in selecting this g r o u p of disorders. The induction period for m a n y c h e m i c a l c a r c i n o g e n s is u s u a l l y fifteen years or greater (4). Very little is known about the health effects of long term, low dose r e s i d e n t i a l e x p o s u r e to c a r c i n o g e n i c agents. The low incidence rates of certain c h i l d h o o d m a l i g n a n c i e s (e.g., lymphomas) in i n d u s t r i a l i z e d c o u n t r i e s suggests that e x p o s u r e to toxic c h e m i c a l s m i g h t not be a m a j o r e t i o l o g i c factor. F i n a l l y the rarity of most c h i l d h o o d m a l i g n a n c i e s in well d e v e l o p e d countries, such as the United States, suggests that "small numbers" m i g h t confound e p i d e m i o l o g i c i n v e s t i g a t i o n s w h i c h use these end points. D e s p i t e these difficulties, the q u e s t i o n of the risk of certain m a l i g n a n c i e s in c o m m u n i t i e s n r o x i m a t e to industrial wastesites must be addressed. Still another group of p o t e n t i a l l y good end ooints for health i n v e s t i g a t i o n s are certain adverse p r e g n a n c y o u t c o m e s (5). S p o n t a n e o u s abortions are e x c e e d i n g l y d i f f i c u l t to study other than in a w e l l - c o n t r o l l e d clinical, p r o s p e c t i v e fashion. This is largely due to the fact that almost half of these events go u n r e c o g n i z e d by patients and/or p h y s i c i a n s (5). Thus, hospital surveys and p h y s i c i a n records are of limited use in ascertainment. A n o t h e r end point with fewer l i m i t a t i o n s is c o n g e n i t a l defects, e s p e c i a l l y the co_mmon major ones. While it has been well e s t a b l i s h e d that these d i s o r d e r s are greatly u n d e r r e p o r t e d in vital records systems, hospital based r e p o r t i n g systems are effective. However one m u s t be selective in the types of m a j o r defects selected for investigation. For example, c o n g e n i t a l heart d i s o r d e r s and cleft palate often go u n r e c o g n i z e d d u r i n g early life. This raises a p o t e n t i a l probelm when e p i d e m i o l o g i c i n v e s t i g a t i o n s are initiated due to the v a r i a b l e age of c h i l d r e n in a given study area (5). In c o n t r a s t spina bifida aperta, a n e n c e p h a l y and cleft lip are rarely m i s s e d at birth (5). Low birth w e i g h t r e p r e s e n t s yet another p o t e n t i a l l y good end point, and in this case vital records g e n e r a l l y provide an excellent v e h i c l e for surveillance. R e g a r d l e s s of the end points selected for health studies, d e t a i l e d c o n s i d e r a t i o n must be given to the wide v a r i e t y of p o t e n t i a l l y c o n f o u n d i n g factors such as past m e d i c a r e and theraputic histories, smoking and alcoholic ingestion.
711
THE E N V I R O N M E N T A L D I S E A S E S U R V E I L L A N C E P R O G R A M IN NEW YORK STATE The p o t e n t i a l health impact of e x p o s u r e to e n v i r o n m e n t a l and o c c u p a t i o n a l toxins has become a m a j o r issue for the public and all levels of government. Faced w i t h i n c o m p l e t e and some times c o n t r a d i c t o r y e v i d e n c e c o n c e r n i n g the health hazards of various chemicals, an aroused public turns to g o v e r n m e n t to a s c e r t a i n whether a hazard exists in their c o m m u n i t y and to e l i m i n a t e it if it does. G o v e r n m e n t a l policymakers, in turn, look to their scientific advisors for answers. However, e f f e c t i v e and sound scientific e v a l u a t i o n of these p r o b l e m s is a lengthy and costly u n d e r t a k i n g b e c a u s e of the inherent d i f f i c u l t i e s in c o l l e c t i n g n e c e s s a r y data. F r e q u e n t l y this process cannot be c o m p l e t e d w i t h i n the time frame a v a i l a b l e for d e c i s i o n making. Thus, p o l i c y m a k e r s are often forced to make d e c i s i o n s of c o n s i d e r a b l e c o n s e q u e n c e based on incomplete information. The Love Canal is a prime example of this f r u s t r a t i n g syndrome. It has taken m o r e than three years at a cost of thousands of d o l l a r s to collect only p r e l i m i n a r y data on people r e s i d i n g near the Canal. In order to address the growing need for health hazard a s s e s s m e n t on toxic w a s t e s i t e s and the growing c o n c e r n s about c o n t a m i n a t i o n of d r i n k i n g water, the New York State Health D e p a r t m e n t i n i t i a t e d the E n v i r o n m e n t a l D i s e a s e S u r v e i l l a n c e P r o g r a m in 1980. The purpose of this p r o g r a m is to d e v e l o p r e g i s t r i e s w h i c h will s y s t e m a t i c a l l y a c c u m u l a t e i n f o r m a t i o n in four broad e n v i r o n m e n t a l areas: heavy metals, e n v i r o n m e n t a l lung disease, c o n g e n i t a l defects, and the use of c o m p o u n d s known or highly s u s p e c t e d to be human carcinogens. A l t h o u g h the effects of acute e x p o s u r e to m e t a l s such as lead, mercury, c a d m i u m and arsenic are well recognized, i n s u f f i c i e n t data exists r e g a r d i n g the effects of l o n g - t e r m chronic exposure. The number of c o m p o u n d s capable of causing p u l m o n a r y fibrosis is rapidly growing, p a r t i c u l a r l y in the p l a s t i c s industry. A v a i l a b l e e v i d e n c e suggests that c o m p o u n d s d e p o s i t e d in the Love Canal are capable of causing r e s p i r a t o r y symptoms if e x p o s u r e is sufficient. Accordingly, some s u r v e i l l a n c e m e c h a n i s m m u s t be d e v e l o p e d to m o n i t o r a s t h m a t i c type syndromes in both the industrial and r e s i d e n t i a l settings w h e r e d u m p s i t e s are present. M a n y c o m p o u n d s some of w h i c h are e s t a b l i s h e d c a r c i n o g e n s have been d e p o s i t e d in v a r i o u s d u m p s i t e s in N e w York State. Benzene and vinyl c h l o r i d e are but two examples. However, the full s p e c t r u m of health effects of these and other substances remains to be determined. The p o s s i b l e i n t e r r e a c t i o n b e t w e e n c o m p o u n d s of this type and agents such as d i o x i n r e q u i r e s further d e t a i l e d investigation. Only by identifying settings similar to the Love Canal and c o n d u c t i n g clinical e p i d e m i o l o g i c a l and t o x i c o l o g i c a l investigations, will we begin to a p p r o a c h answers to m a n y of these u n r e s o l v e d questions. It is well e s t a b l i s h e d that the fetus is highly s u s c e p t i b l e to certain c h e m i c a l agents (6). There is great p o t e n t i a l value in studying the i n c i d e n c e of various c o n g e n i t a l defects and other adverse p r e g n a n c y o u t c o m e s in both industrial and chemical d u m p s i t e settings. All of these i n i t i a t i v e s will h o p e f u l l y provide a m e a n s of e f f i c i e n t l y e v a l u a t i n g the central issue of human health hazards in p o t e n t i a l l y harmful settings.
712
REFERENCES i. Love Canal, Public Health New York State D e p a r t m e n t 2. Love Canal, A Special Legislature, New York
Time Bomb, of Health,
September, Albany.
1978,
Report to the G o v e r n o r and State D e p a r t m e n t of Health,
Albany
3. C h e m i c a l C o n t a m i n a t i o n in the Human E n v i r o n m e n t by M. L i p p m a n and D. Collins, Oxford U n i v e r s i t y Press,
1970
4. Monitoring, Birth Defects and E n v i r o n m e n t by E. Hook, D. J a n e r i c h and I. Porter, Sec. III A, pp. 85-96, A c a d e m i c Press, 1971. 5. Monitoring, Birth Defects and E n v i r o n m e n t D. J a n e r i c h and I. Porter, Sec. II B, pp. A c a d e m i c Press, 1971.
by E. Hook, 65-81,
6. Persons at High Risk of Cancer, An A p p r o a c h to Cancer E t i o l o g y and Control; J. Fraumeni, Jr., ed., Chap. ii, pp. 167-184, A c a d e m i c Press, 1975.
705--712,1983
THE LOVE CANAL:
Nicholas
0 0 4 5 6535/83/050705-.08503.00/0 © 1 9 8 3 ~ e r g a m o n Press Ltd.
ISSUES AND P R O B L E M S
J. Vianna,
M.D.,
M.S.P.H.
N e w York State D e p a r t m e n t of H e a l t h D i v i s i o n of H e a l t h Risk C o n t r o l Albany, N e w York 12237
The Love Canal has come to s y m b o l i z e the m a n y p r o b l e m s and u n r e s o l v e d s c i e n t i f i c issues r e l a t i n g to the d i s p o s a l of i n d u s t r i a l w a s t e p r o d u c t s in landfills. S i t u a t i o n s of this type are e x c e e d i n g l y c o m p l e x since they d i r e c t l y impact on the social, psychologic, and e c on o m i c w e l l - b e i n g of the involved community. U n d e r l y i n g all of these issues is the f u n d a m e n t a l q u e s t i o n w h e t h e r r e s i d i n g in c l o s e p r o x i m i t y to an i n d u s t r i a l w a s t e s i t e r e p r e s e n t s a h e a l t h h a z a r d for area residents. A clear u n d e r s t a n d i n g of the Love C a n a l p r o b l e m n e c e s s i t a t e s a c h a r a c t e r i z a t i o n of the types of c h e m i c a l s located in the d u m p s i t e and p o s s i b l e paths of migration. T h e s e factors m u s t in turn be i n t e r p r e t e d in light of the t e m p o r a l d e v e l o p m e n t of the area. This r e p o r t will r e v i e w the h i s t o r i c a l d e v e l o p m e n t of the Love Canal area and the c h e m i c a l and e p i d e m i o l o g i c a l e f f o r t s that were i n i t i a t e d by the State of N e w York. M a j o r e m p h a s i s will be p l a c e d on some of the m a j o r s c i e n t i f i c issues e n c o u n t e r e d in each of these i n v e s t i g a t i o n s .
HISTORY
OF THE LOVE C A N A L
The Love Canal is a r e c t a n g u l a r , sixteen-acre, b e l o w - g r o u n d level landfill site located in a r e s i d e n t i a l section of the s o u t h e a s t corner of N i a g a r a City, N e w York (1,2). In the late n i n e t e e n t h century, the site was e x c a v a t e d as part of a p r o p o s e d canal linking the N i a g a r a River and Lake Ontario. The p u r p o s e of the Canal was to p r o d u c e h y d r o e l e c t r i c power for use in a model city. In 1938 the Canal was a p p r o x i m a t e l y 3000 feet long and 100 feet wide and there was no e v i d e n c e of w a s t e disposal. The Love Canal p r o j e c t was a b a n d o n e d and was s u b s e q u e n t l y used for d i s p o s a l of c h e m i c a l w a s t e s (e.g., c h l o r i n a t e d h y d r o c a r b o n residues, p r o c e s s e d sludges, flyash) until about 1953 (1,2). A e r i a l p h o t o g r a p h s of the study area from 1938 show h o u s i n g c o n f i n e d a l m o s t e x c l u s i v e l y to 101st, 102nd, and 103rd Streets in the form of s i n g l e - f a m i l y houses and farms (Figure i). By 1951, there were still no homes on 197th Street, but a few new houses were p r e s e n t on the s o u t h e a s t e r n sections of 99th through 103rd Streets. H o u s i n g c o n s t r u c t i o n p r o c e e d e d t h r o u g h the 1960's and was m o s t l y c o m p l e t e d on 99th Street by 1965, but c o n t i n u e d on 97th Street through 705
706
•I// //.d
;ATMt ~At,
\
Figure 1
707
1973. Presently, the site is c o n t a i n e d w i t h i n the area b o r d e r e d by C o l v i n Avenue, F r o n t i e r A v e n u e and 99th Street (Figure i). S o u t h e r n and n o r t h e r n sections of the o r i g i n a l Love C a n a l are b o r d e r e d by the b a c k y a r d s of s i n g l e - f a m i l y homes on 97th and 99th Streets, w h i l e the m i d d l e section is o c c u p i e d by an e l e m e n t a r y school. By 1972 v i r t u a l l y all houses w h o s e b a c k y a r d s d i r e c t l y abut the Love Canal were completed. An i m p o r t a n t feature for the c o r r e l a t i o n b e t w e e n i l l n e s s e s and c h e m i c a l leachates were the natural d r a i n a g e ways o f f e r i n g p r e f e r e n t i a l routes for the m o v e m e n t of liquids underground. In fact deep d e p r e s s i o n s or swales (Figure i) t r a v e r s e d the area, some i n t e r s e c t i n g the Love C a n a l itself. These swales w e r e shallow, g e n e r a l l y no m o r e than six feet deep, and c o n t a i n e d water p r i m a r i l y d u r i n g the wet season. The m a j o r swale i n t e r s e c t e d the C a n a l ' s n o r t h e r n section and p a s s e d to the east of it along a n o r t h w e s t - s o u t h e a s t line to 103rd Street (Figure i). The p r e c i s e l o c a t i o n of these swales was d e t e r m i n e d from aerial p h o t o g r a p h s taken in 1938, 1951 and 1966, as i n d e p e n d e n t l y i n t e r p r e t e d by the C o r n e l l School of Civil and E n v i r o n m e n t a l Engineering. As the area was developed, the contour and e x t e n t of these swales was s u b s t a n t i a l l y modified. D e v e l o p m e n t of the area b e t w e e n 1951 and 1956 e l i m i n a t e d the m a j o r swale w h i c h i n t e r s e c t e d the Canal as a c o n t i n u o u s c o n d u i t of surface water flow from the Canal to p e r i p h e r a l areas (Figure i). In 1953 Hooker C h e m i c a l C o m p a n y sold the Love Canal to the N i a g a r a Falls Board of Education, and one year later an e l e m e n t a r y school was built on this p r o p e r t y (Figure i).
CHEMICAL
INVESTIGATION
E x t e n s i v e e n v i r o n m e n t a l testing was r e q u i r e d to i d e n t i f y m o s t of the c h e m i c a l c o m p o u n d s p r e s e n t in the Love Canal at the time N e w York State H e a l t h D e p a r t m e n t studies were initiated. T a b l e 1 lists some of the m o r e than 200 c h e m i c a l s thus far i d e n t i f i e d in this w a s t e s i t e (2). Table
1
Some of the more
important
chemicals
identified
Chloroform
Pentachlorobenzene
Carbon
Allyl
tetrachloride
phenols
l.l-dichloroethane
Hexachlorobenzene
1.2-dichloroethane
Tetra,
penta,
hexa
l.l.l-trichloroethane
chlorinated
Trichloroethylene
or p h e n a n t r a c e n e s
Tetrachloroethylene
2,3,7,8-TCDD
Chlorobenzene Dichlorobenzene
at Love Canal
antracenes
and other T C D D s
Hexachlorodibenzodioxin (2 isomers)
Dichlorodibenzodioxin
1,2-dichloropropane
Chlorinated
Chlorotoluene
Trichlorophenols
(2 isomers)
naphthalenes (isomers)
708
Chlorobenzaldeyde Dichlorotoluene
(isomers) (3 isomers)
Dichlorobenzaldeyde Trichlorobenzene
PCBs
(isomers)
Octachlorocyclopentane
(isomers)
(3 isomers)
1,2-dibromoethane Trichlorotoluene
(5 isomers)
Tetrachlorotoluene
(isomers)
Tetrachlorobenzene
(3 isomers)
Benzene Toluene v.s.p.
Xylenes
Benzaldeyde Chlorotoluenes
The first 21 c h e m i c a l s have been i d e n t i f i e d by both the EPA and by the N e w York State H e a l t h Department. The r e m a i n i n g c o m p o u n d were identified by the N.Y. State H e a l t h D e p a r t m e n t Dioxin (2,3,7,8 t e t r a c h l o r o d i b e n z o - p a r a d i o x i n ) was one of the c h e m i c a l s found in the landfill. Its p r e s e n c e was p r o b a b l y due to the fact that the Hooker C h e m i c a l C o m p a n y buried a p p r o x i m a t e l y 200 tons of t r i c h l o r o p h e n o l s in the Love Canal between 1942 and 1953. It is well e s t a b l i s h e d that d i o x i n is a c o n t a m i n a n t b y p r o d u c t formed d u r i n g the m a n u f a c t u r e of t r i c h l o r o p h e n o l s . Several a n a l y s e s have d e m o n s t r a t e d the p r e s e n c e of this c h e m i c a l in soil samples from the landfill, the b a c k y a r d s of nearby homes and the sediment and m a r i n e life of two oceans b o a r d e r i n g the Love Canal neighborhood. To date the highest c o n c e n t r a t i o n of d i o x i n found is a p p r o x i m a t e l y 300 parts per b i l l i o n in a storm sewer a d j o i n i n g the Canal area. This o b s e r v a t i o n is of great p o t e n t i a l importance since a v a i l a b l e evidence suggests that between 1957 and 1960 at least two sewer pipes were laid right through the Canal ten feet b e l o w the surface The gravel bed g e n e r a l l y used around these pipes could provide a p o t e n t i a l conduit for the m i g r a t i o n of certain c h e m i c a l s buried w i t h i n the wastesite. The chemical i n v e s t i g a t i o n s at the Love Canal have raised m a n y u n r e s o l v e d issues. C l e a r l y all of the c h e m i c a l s d e p o s i t e d in the site have not been identified. Of the hundreds of c h e m i c a l s found, w h i c h ones should be m o n i t o r e d and what types of samples should be o b t a i n e d (e.g., air, water, soil)? Special care m u s t be taken in the c o l l e c t i o n of e n v i r o n m e n t a l samples and the issue of specimen h o m o g e n e i t y must o b v i o u s l y be a d d r e s s e d (3). C l e a r l y c e r t a i n c h a r a c t e r i s t i c s of soil can influence chemical analyses. The humic f r a c t i o n in m a n y a g r i c u l t u r a l soils is c o m p o s e d of lipids w h i c h can i m m o b i l i z e f a t - s o l u b l e o r g a n o c h l o r i n e pesticides. C e r t a i n inorganic c h e m i c a l s may p e r c i p i t a t e out in soil water as oxides. D e t a i l e d c o n s i d e r a t i o n m u s t also be g i v e n to the m o d e s d e g r a d a t i o n and half life of c h e m i c a l s s e l e c t e d for
of
709
surveillance. This is an i m p o r t a n t issue p a r t i c u l a r l y w h e n c u r r e n t c h e m i c a l a n a l y s e s are being used to gain some insight into the types of c o m p o u n d s d e p o s i t e d in prior years. F u r t h e r i n v e s t i g a t i o n of the date and r e s i d e n c e times of c h e m i c a l s in d i f f e r e n t types of soil is an i m p o r t a n t p r i o r i t y in future research. Still o t h e r p r o b l e m s became e v i d e n t in the c o u r s e of our investigations. The h u m a n t o x i c i t y of c o m p o u n d s such as tetrachlorodibenzo-p-dioxin (TCDD) has not been fully d e l i n e a t e d and there are m a r k e d v a r i a t i o n s in the s u s c e p t i b i l i t y of d i f f e r e n t animal species to this compound. In c e r t a i n animal m o d e l s TCDD p r o m o t e s c a r c i n o g e n i c i t y . G i v e n the large number of c h e m i c a l s found in the Love C a n a l the p o s s i b i l i t y of synergistic, a d d i t i v e or a n t a g o n i s t i c r e a c t i o n s m u s t be considered. Ideally these issues are e v a l u a t e d in l a b o r a t o r y s e t t i n g s under c o n t r o l l e d c i r c u m s t a n c e s . U n f o r t u n a t e l y it is e x c e e d i n g l y d i f f i c u l t to s i m u l a t e the field c o n d i t i o n s of a c h e m i c a l w a s t e s i t e in a laboratory. Perhaps a partial answer to this d i f f i c u l t y is to c o n d u c t t o x i c o l o g i c studies on the wild animal life i n d i g e n o u s to the area u n d e r investigation. The use of n a t i v e plants in such studies m i g h t be somewhat limited since u p t a k e of m a n y c h e m i c a l c o n t a m i n a n t s m i g h t be only temporary.
HEALTH
INVESTIGATIONS
The f u n d a m e n t a l q u e s t i o n u n d e r l y i n g all toxic w a s t e s i t e s is w h e t h e r they r e p r e s e n t a h e a l t h hazard to man. U n f o r t u n a t e l y this is a m o s t d i f f i c u l t issue to fully address. W i t h o u t some k n o w l e d g e about the c h e m i c a l c o n t e n t s in a wastesite, it is v i r t u a l l y i m p o s s i b l e to c o n d u c t m e a n i n g f u l studies. In s e t t i n g s w h e r e there is no r e c o r d of the c h e m i c a l s deposited, it is e x c e e d i n g l y d i f f i c u l t to d e t e r m i n e what to test for. Even w h e n such d e c i s i o n s are made, the c o n f o u n d i n g i n f l u e n c e of c h e m i c a l s found in h o u s e h o l d and lawn p r o d u c t s (e.g., detergents, fertilizers, pesticides) has to be considered. In addition, m o s t sites d i f f e r with r e g a r d to some i m p o r t a n t v a r i a b l e s including their c h e m i c a l c o n t e n t s and their method(s) of storage, the m o d e of c o n s t r u c t i o n of the site, soil and h y d r o g e o l o g i c a l c h a r a c t e r i s t i c s , routes of p o t e n t i a l m i g r a t i o n that are manmade, and p r o x i m i t y to w a t e r supplies. D e s p i t e these and other m a j o r d i f f i c u l t i e s , the central issue of human h e a l t h m u s t be addressed. C l e a r l y this is the r e s p o n s i b i l i t y of the c l i n i c a l and e p i d e m i o l o g i c d i s c i p l i n e s . H e a l t h risk a s s e s s m e n t e s t i m a t e s based on animal studies, w h i l e p a r t i c u l a r l y useful in s i t u a t i o n s w h e r e there is no h u m a n data, will never fully satisfy the c o n c e r n s of p o t e n t i a l l y e x p o s e d residents. The s e l e c t i o n of h e a l t h end points m u s t d e p e n d to a large extent on the types of c h e m i c a l s p r e s e n t and their e s t a b l i s h e d effects on man. M a n y c o m p o u n d s found in the Love Canal are e s t a b l i s h e d skin i r r i t a n t s (e.g., benzene, b e n z o i c acid, t r i c h l o r o e t h y l e n e and chloroform) (i). O t h e r s such as carbon t e t r a c h l o r i d e can c a u s e toxic h e p a t i t i s (i). Still others (e.g., lindane) can p r o d u c e frank c o n v u l s i o n s if s u f f i c i e n t amounts are ingested
(i)
.
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Accordingly, these d i s o r d e r s are good "acute end points" to study in this setting. Greater d i f f i c u l t y is e n c o u n t e r e d when one attempts to identify a p p r o p r i a t e d i s e a s e states w h i c h m i g h t be i n d i c a t i v e of "chronic e x p o s u r e to toxic chemicals". The c a r c i n o g e n i c effect of m a n y chemical compounds is well e s t a b l i s h e d in certain o c c u p a t i o n a l settings. In addition, d e a th c e r t i f i c a t e s g e n e r a l l y provide a r e a d i l y a v a i l a b l e m e a n s of m o n i t o r i n g various cancers in specific g e o g r a p h i c areas. These facts suggest that m a l i g n a n t d i s o r d e r s m i g h t r e p r e s e n t end points for e n v i r o n m e n t a l monitoring. This is e s p e c i a l l y true of children, since the s e l e c t i o n of this age g r o u p e s s e n t i a l l y eliminates the influence of o c c u n a t i o n a l factors. But there are some serious l i m i t a t i o n s in selecting this g r o u p of disorders. The induction period for m a n y c h e m i c a l c a r c i n o g e n s is u s u a l l y fifteen years or greater (4). Very little is known about the health effects of long term, low dose r e s i d e n t i a l e x p o s u r e to c a r c i n o g e n i c agents. The low incidence rates of certain c h i l d h o o d m a l i g n a n c i e s (e.g., lymphomas) in i n d u s t r i a l i z e d c o u n t r i e s suggests that e x p o s u r e to toxic c h e m i c a l s m i g h t not be a m a j o r e t i o l o g i c factor. F i n a l l y the rarity of most c h i l d h o o d m a l i g n a n c i e s in well d e v e l o p e d countries, such as the United States, suggests that "small numbers" m i g h t confound e p i d e m i o l o g i c i n v e s t i g a t i o n s w h i c h use these end points. D e s p i t e these difficulties, the q u e s t i o n of the risk of certain m a l i g n a n c i e s in c o m m u n i t i e s n r o x i m a t e to industrial wastesites must be addressed. Still another group of p o t e n t i a l l y good end ooints for health i n v e s t i g a t i o n s are certain adverse p r e g n a n c y o u t c o m e s (5). S p o n t a n e o u s abortions are e x c e e d i n g l y d i f f i c u l t to study other than in a w e l l - c o n t r o l l e d clinical, p r o s p e c t i v e fashion. This is largely due to the fact that almost half of these events go u n r e c o g n i z e d by patients and/or p h y s i c i a n s (5). Thus, hospital surveys and p h y s i c i a n records are of limited use in ascertainment. A n o t h e r end point with fewer l i m i t a t i o n s is c o n g e n i t a l defects, e s p e c i a l l y the co_mmon major ones. While it has been well e s t a b l i s h e d that these d i s o r d e r s are greatly u n d e r r e p o r t e d in vital records systems, hospital based r e p o r t i n g systems are effective. However one m u s t be selective in the types of m a j o r defects selected for investigation. For example, c o n g e n i t a l heart d i s o r d e r s and cleft palate often go u n r e c o g n i z e d d u r i n g early life. This raises a p o t e n t i a l probelm when e p i d e m i o l o g i c i n v e s t i g a t i o n s are initiated due to the v a r i a b l e age of c h i l d r e n in a given study area (5). In c o n t r a s t spina bifida aperta, a n e n c e p h a l y and cleft lip are rarely m i s s e d at birth (5). Low birth w e i g h t r e p r e s e n t s yet another p o t e n t i a l l y good end point, and in this case vital records g e n e r a l l y provide an excellent v e h i c l e for surveillance. R e g a r d l e s s of the end points selected for health studies, d e t a i l e d c o n s i d e r a t i o n must be given to the wide v a r i e t y of p o t e n t i a l l y c o n f o u n d i n g factors such as past m e d i c a r e and theraputic histories, smoking and alcoholic ingestion.
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THE E N V I R O N M E N T A L D I S E A S E S U R V E I L L A N C E P R O G R A M IN NEW YORK STATE The p o t e n t i a l health impact of e x p o s u r e to e n v i r o n m e n t a l and o c c u p a t i o n a l toxins has become a m a j o r issue for the public and all levels of government. Faced w i t h i n c o m p l e t e and some times c o n t r a d i c t o r y e v i d e n c e c o n c e r n i n g the health hazards of various chemicals, an aroused public turns to g o v e r n m e n t to a s c e r t a i n whether a hazard exists in their c o m m u n i t y and to e l i m i n a t e it if it does. G o v e r n m e n t a l policymakers, in turn, look to their scientific advisors for answers. However, e f f e c t i v e and sound scientific e v a l u a t i o n of these p r o b l e m s is a lengthy and costly u n d e r t a k i n g b e c a u s e of the inherent d i f f i c u l t i e s in c o l l e c t i n g n e c e s s a r y data. F r e q u e n t l y this process cannot be c o m p l e t e d w i t h i n the time frame a v a i l a b l e for d e c i s i o n making. Thus, p o l i c y m a k e r s are often forced to make d e c i s i o n s of c o n s i d e r a b l e c o n s e q u e n c e based on incomplete information. The Love Canal is a prime example of this f r u s t r a t i n g syndrome. It has taken m o r e than three years at a cost of thousands of d o l l a r s to collect only p r e l i m i n a r y data on people r e s i d i n g near the Canal. In order to address the growing need for health hazard a s s e s s m e n t on toxic w a s t e s i t e s and the growing c o n c e r n s about c o n t a m i n a t i o n of d r i n k i n g water, the New York State Health D e p a r t m e n t i n i t i a t e d the E n v i r o n m e n t a l D i s e a s e S u r v e i l l a n c e P r o g r a m in 1980. The purpose of this p r o g r a m is to d e v e l o p r e g i s t r i e s w h i c h will s y s t e m a t i c a l l y a c c u m u l a t e i n f o r m a t i o n in four broad e n v i r o n m e n t a l areas: heavy metals, e n v i r o n m e n t a l lung disease, c o n g e n i t a l defects, and the use of c o m p o u n d s known or highly s u s p e c t e d to be human carcinogens. A l t h o u g h the effects of acute e x p o s u r e to m e t a l s such as lead, mercury, c a d m i u m and arsenic are well recognized, i n s u f f i c i e n t data exists r e g a r d i n g the effects of l o n g - t e r m chronic exposure. The number of c o m p o u n d s capable of causing p u l m o n a r y fibrosis is rapidly growing, p a r t i c u l a r l y in the p l a s t i c s industry. A v a i l a b l e e v i d e n c e suggests that c o m p o u n d s d e p o s i t e d in the Love Canal are capable of causing r e s p i r a t o r y symptoms if e x p o s u r e is sufficient. Accordingly, some s u r v e i l l a n c e m e c h a n i s m m u s t be d e v e l o p e d to m o n i t o r a s t h m a t i c type syndromes in both the industrial and r e s i d e n t i a l settings w h e r e d u m p s i t e s are present. M a n y c o m p o u n d s some of w h i c h are e s t a b l i s h e d c a r c i n o g e n s have been d e p o s i t e d in v a r i o u s d u m p s i t e s in N e w York State. Benzene and vinyl c h l o r i d e are but two examples. However, the full s p e c t r u m of health effects of these and other substances remains to be determined. The p o s s i b l e i n t e r r e a c t i o n b e t w e e n c o m p o u n d s of this type and agents such as d i o x i n r e q u i r e s further d e t a i l e d investigation. Only by identifying settings similar to the Love Canal and c o n d u c t i n g clinical e p i d e m i o l o g i c a l and t o x i c o l o g i c a l investigations, will we begin to a p p r o a c h answers to m a n y of these u n r e s o l v e d questions. It is well e s t a b l i s h e d that the fetus is highly s u s c e p t i b l e to certain c h e m i c a l agents (6). There is great p o t e n t i a l value in studying the i n c i d e n c e of various c o n g e n i t a l defects and other adverse p r e g n a n c y o u t c o m e s in both industrial and chemical d u m p s i t e settings. All of these i n i t i a t i v e s will h o p e f u l l y provide a m e a n s of e f f i c i e n t l y e v a l u a t i n g the central issue of human health hazards in p o t e n t i a l l y harmful settings.
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REFERENCES i. Love Canal, Public Health New York State D e p a r t m e n t 2. Love Canal, A Special Legislature, New York
Time Bomb, of Health,
September, Albany.
1978,
Report to the G o v e r n o r and State D e p a r t m e n t of Health,
Albany
3. C h e m i c a l C o n t a m i n a t i o n in the Human E n v i r o n m e n t by M. L i p p m a n and D. Collins, Oxford U n i v e r s i t y Press,
1970
4. Monitoring, Birth Defects and E n v i r o n m e n t by E. Hook, D. J a n e r i c h and I. Porter, Sec. III A, pp. 85-96, A c a d e m i c Press, 1971. 5. Monitoring, Birth Defects and E n v i r o n m e n t D. J a n e r i c h and I. Porter, Sec. II B, pp. A c a d e m i c Press, 1971.
by E. Hook, 65-81,
6. Persons at High Risk of Cancer, An A p p r o a c h to Cancer E t i o l o g y and Control; J. Fraumeni, Jr., ed., Chap. ii, pp. 167-184, A c a d e m i c Press, 1975.