Document 3QXX5vdQng2LK1z2awVJk2O9D

Organochlorine Pollutants in Peregrines and Merlins Migrating through Wisconsin KoniiXT W. Rishurough Department of Nutritional Science* InMiiiiie of Marine Ketourus University of California Berkeley, California 94720 ' GREOORV I.. PlORANT l.nhortnr\ >. Ornithnlop.v, f orneJI VJnivtrv">. tihiici*. New Vork Imniel O. Berger 1328 N. Jefferson ' Milwaukee, Wisconsin 33202 / 1 The discovery that the Peregrines (Falco pertlirlnus) breeding in the eastern Arctic are laying Kjhin-shclled eggs and are showing symptoms of /reproductive failure (Berger rf of., this Issue) ^VHuefcxtithat this population is beginning to be afl|ffni>y the same extinction process that has rcsulled in the extirpation of breeding Pere grines in many areas of North America and Euro^(Hickey.l969; RatclilTe, 1970). The PerejHgs of the eastern United States dlsap- peareTbefore the nature of the extinction pro cess was evident, but subsequent research showed that eggshell thinning had been associatm with the population decline (Hickey and Anjjmon, 1968). In Great Britain there was a bSpsiderable amount of evidence that exces sive mortality of adult birds had been a major reason for the rapid decline that began around 1955, j^Rjding with the introduction of highly toxic insecticides such as dieldrin into agricul tural use (Ralcliffe, 1963; Jefferies and Prestt, 1966). The surviving birds, however, exper ienced reproductive failures that were charac terized by shell thinning, egg breakage, and eal ing of the eggs by the adult birds (Ratcliffe, 1967; Ratcliffe, 1970). Although embryonic mortality may be contributing to the decline in reproductive oapacity of the Ungava Peregrines (Berger**! al., this issue) the pattern of egg breakage associated with shell thinning now observed in this population appears to be iden tical to the symptoms noted previously in touth- ern Canada (Hall, this issue), the United States (Hickey and Anderson, 1968) and Great Britain (Ratcliffe, 1970). At the conference convened in Madison, Wisconsin, by J. J. Hickey in 1963 to examine the causes of disappearance of the Peregrine from the eastern United States, all conceivable factors were considered in detail. Among these, only environmental pollution was consistent with the pattern of extinction observed in Peregrine populations in both Europe and North Amerioa (Hickey, 1969). Since repro ductive failure now appears to threaten the survival of the Arctic populations, it has be come imperative to determine more precisely the particular pollutants responsible. In addition to the evidence relating excessive adult mortality to the use of several of the more toxic of the chlorinated hydrocarbon insecti cides, Ratcliffe (1970) has accumulated a con siderable amount of data relating the shell thinning among British birds of prey to the environmental distribution of organochlorine pollutants, including both insecticides with their derivatives and industrial compounds. The latter consist primarily Of polychlorinated biphenyls which have become widespread and locally abundant pollutants (Jensen ft al., 1969; Kocman el al., 1969; Risebrough et al.. 1968). Other pollutants that might be contribu ting to the decline of the North American Peregrines include mercury and lead. Mercury MONS 097769 248 The Canadian Field-Naturalist Vol. 84 is more widespread in the environment than months old. Seven were biopsied in 1968 and wns previously suspected (Fimreite et a/., this three in 1969. All of the Merlin samples were issue). Waterfowl may accumulate lead from obtained in 1969. Three were adult males, one ingested shotgun pellets (Baglcy and Locke, an adult female, and the remaining three were 1967) and Peregrines preying upon them might immalures of the year. acquire dangerous concentrations. There is as The biopsy technique has been described yet, however, no evidence that links either metal previously (Endcrson and Berger, 1968). There at environmental concentrations to the shell have been no indications that this procedure thinning phenomenon. Proof is rapidly accumu harms the birds in any way. Biopsy samples lating, however, that one or more of the chlor have been obtained from Harriers (Circus inated hydrocarbons, particularly the DDT cyaneus) that have been observed for many compound DDE, may induce shell thinning months afterwards (Frances Hamerstrom, per under both environmental and experimental sonal communication). conditions (Hickey and Anderson. 1968; Porter The adipose tissue biopsy samples were and Wiemeyer, 1969; Heath et al,, 1969; frozon, either in acetone-washed glass vials Anderson et of.. 1969). Very small concentra capped with aluminum (oil, or in sterile packets tions of DDE are associated with significant lined internally with aluminum foil which are changes in shell thickness in eggs of the Brown used in medicine for antiseptic gauzes. The Pelican (Pelecama occidentalis) (Risebrough, samples were weighed in the laboratory to ob Anderson and Schreiber, unpublished observa tain wet weights and then ground in a Waring tions). The role of DDE and of other chlorin blendor with anhydrous sodium sulfate. Lipids ated hydrocarbons found in the environment were obtained by soxhlet extraction for at least such as dieldrin and the polychlorinated bi six hours with a hot mixture of two parts of phenyls in producing additional sublethal effects hexane and one part of acetone. The organic that might interfere with reproduction is as yet solvents were removed by evaporation. When unclear. Delayed breeding or abnormalities in small amounts of sodium sulfate were carried behaviour could be associated with the high over into the extract, the lipid was dissolved in rale of steroid degradation caused by the liver petroleum ether and washed with water. enzymes induced by these compounds (Jefferies, The biopsy samples were small. The Pere 1967; Peakall, 1970). The volume that emerged grine samples averaged 0.49 grams, with a range from the 1965 conference in Madison (Hickey, from 0.0496 to 0.983 gm, and the Merlins 1969) concludes with the statement by Hickey averaged 0.162 gm, with a range from 0.0497 to and Roelle "How much industrial pollutants like 0.5608 gm. Some samples were found to consist the polychlorinated biphenyls have also contri mainly of connective tissue rather than lipid. buted to some of these phenomena promises to The Peregrine samples consisted of an average be an absorbing chapter in the research of the of 69% by weight of extractable lipid, with a immediate future" (Hickey and Roelle, 1969). range from 31% to 91%. One Merlin sample The present paper reports on the polychlorina consisted of only 5% lipid, the average percent ted biphenyls and other ohlorinated hydro lipid among the Merlin samples was 35%, and carbons in fat biopsy samples obtained from ten the highest value was 68%. Peregrines and seven Merlins (Pigeon Hawk, The lipid extracts were dried at 65 for 8-12 Faico columbarius) trapped at the Cedar Grove hours, weighed in the beakers, dissolved in Ornithological Station on the western shore of hexane and divided into one or more aliquots. Lake Michigan during the fall migrations of The aliquot analysed for the DDT and PCB 1968 and 1969. compounds was passed through a modified Materiala and Methods Davidow column (Stanley and LeFavoure, 1965). This column, consisting of celite, sul All of the Peregrines ware immature birds of furic acid and fuming sulfuric acid, permits the year and therefore approximately three rapid cleanup with quantitative recov- i I l I | t I I I i I I i I I i i i i i i i t * i i i i M0NS 097770 1970 RlSfiBROUCH T. At.! POLLUTAKTB IN PEREGRINES AND MERLINS 249 cries of tlic DDT compounds und PCB. of the polychlorinated biphenyls encountered in Allhough not an important factor for the environmental samples. DDE frequently con present study, it permits much larger amounts stitutes 90% or more of the DDT compounds of lipid material to be treated at one time than present in wildlife. The electron capture re docs the (lorisil method. This procedure, how sponse of DDE is considerably greater than 4*1 m ever destroys dicldrin and to determine this that of PCli, and although one of the PCB compound another method must be employed. compounds emerges at approximately the same Another aliquot of the lipid extract, in hexane, time as DDE, the error introduced in the DDE m was partitioned twice with acetonitrile, the determination is less than experimental error in vt combined acetonitrile fractions were evaporated even when the total PCB concentration is up to to tliym'ss, retlissolved in petroleum ether, and five times that of the DDE. Vermeer and Rey y tf* applied to a llorisil column. The column was nolds (1970) have commented upon the diffi rinsed first with 200 ml of petroleum ether and culty in separating the DDT compounds p.p'- n ill tti re he 200 ml of 6% ethyl ether in petroleum ether. Dicldrin was eluted by passing 200 ml of 15% ethyl ether In petroleum ether through the col umn. Controls had indicated that 90% or more of the dicldrin applied to a florisil column eluted DDD and p.p'-DDT from PCB. On the DC-200 column, both DDT compounds emerge at approximately the same time as a PCB peak (Anderson rr al., 1969). On the OF-1 column, however, there is no interference between p.p'- I** in this fraction. DDT and any of the polychlorinated biphenyls Blank samples consisting of redistilled petro usually encountered in environmental samples. H 4i leum ether analysed through the entire proce Although many different chlorinated biphenyl M dure showed no substances that might interfere compounds are released into the environment, of with the determination of any of the chlorinated-' relatively few persist in the higher levels of food le hydrocarbons reported here. chains. Moreover, these are found in approxi The extracts were analysed with a Microtek mately the same proportions in environmental id gas chromatograph equipped with a tritium and samples over wide areas of the world. The In a nickel-63 electron capture detector. Glass chromatograms of the PCB compounds in the columns were used containing 3% QF-I, or a Peregrines analysed in the present study are mixture of 3% QF-1 and 10% DC-200, on therefore similar to the chromatograms of Pere * Chromosorb W, 80-100 mesh, acid washed and grine extracts from Mexico, California, and HMDS treated. Amchitka Island (Risebrough, unpublished re w Other laboratories (Reynolds, 1969; Armour sults). Moreover, the chromatograms are similar it and Burke, 1970) have developed methods for to those obtained from extracts of Brown 1 separating the polychlorinated biphenyls from Pelican eggs from several areas in both North ft* some or all of the chlorinated hydrocarbons of and South America (Risebrough, -unpublished insecticide origin. The polychlorinated biphenyl results). It is frequently possible, therefore, to It compounds emerge at different times from the treat the PCB mixture as a single compound it gas chromatograph and occasionally a peak may and to obtain accurate relative concentiations 4 coincide or interfere with the peak produced of PCB using any one of the several peaks. The by one of the insecticides. We have found it peak emerging at the same time as p.p'-DDD 2 possible, however, to quantify PCB, DDE. on the OF-1 column is almost always of the n p,p'-DDD, p.p'-DDT, dicldrin and endrin on same height as two of the other peaks. It is ai. the basis of the procedure outlined above, with therefore possible to obtain a crude estimate of out any attempt at separating the PCB. Dieldrin the DDD present without initial separation of d and DDE emerge at exactly the same time on the PCB. This assumption may be tested and the j, the DC-200 column, but on the QF-1 column identification of p.p'-DDT and p.p'-DDD con there it no significant interference between firmed by saponification (Anderson tl al., 1969; dieldrin and DDE, or between dieldrin and any Risebrough et al., 1969). An aliquot of the MQNS 097771 250 The Canadian Field-Naturalist Vol. 84 extract, in hexane or petroleum ether, is re fluxed in 5% KOH in ethyl alcohol. The hexane is then separated from the alcohol and potassium hydroxide by the addition of water and a sample Injected into the gas chromatograph. The pro cedure converts both DOT and DDD to their ably a result of interference by PCB in Ihe earlier determinations (Anderson era/., 1969). The dieldrin values arc equivalent to those previously reported and there is no significant difference in the DDE concentrations. On a lipid basis, the average values reported by WARF, respective ethylene derivatives, DDE and DDMU, but leaves the PCB profile of the chromatograms unchanged. Inc. were 19.3 ppm DDE, 0.8 ppm DDD, 1.2 ppm p.p'-DDT and 0.3 ppm dieldrin (Enderson and Berger, 1968). Since the profile of the PCB peaks was First year immature Peregrines migrating similar, but not identical to the profile observed from the Arctic have therefore low residues of in chromatograms of the commercial prepara DDE. Unfortunately little is known about the tion Aroclor 1254, PCB was quantified by relationships among dietary levels of DDE and comparing the total area of the PCB peaks PCB, equilibrium concentrations of these com emerging after DDE with the areas of the same pounds in various tissues, and the times required penks in chromatograms of standard Aroclor 1254. The procedure is therefore arbitrary, but permits the determination of relative. amounts of PCB within the correct order of magnitude of absolute amounts. Moreover, the values ob tained can be readjusted as methodology is Improved. to achieve an equilibrium concentration. The low concentrations found in these Peregrines presumably reflect therefore both the age of the birds, which possibly has not permitted them to accumulate the high concentrations found in adults, and lower levels of contamination found in some of the prey species. An understanding Results and Discussion of the pharmacodynamics of DDE and PCB in birds is one of the conspicuous deficiencies in Enderson and Berger (1968) have previously our knowledge in the field of pollution ecology. reported on the chlorinated hydrocarbon resi Within several ecosystems so far studied, the dues found in biopsy fat samples from immature concentrations of DDE in birds tends to parallel Peregrines that were also trapped during fall the concentrations of PCB. The ratio may be migration at Cedar Grove, Wisconsin. These approximately one to one, as in San Francisco samples, analysed by the Wisconsin Alumni Bay (Riscbrough er of., 1968). DDE is several Research Foundation in Madison, Wisconsin, times more abundant than PCB in several ` contained an average concentration of 19.4 Pacific marine ecosystems (Risebrough er al., ppm of DDE on a lipid basis. DDE concentra 1968), but in Florida, PCB is approximately tions in the fat of females at the Arctic breeding three timet as abundant as DDE in the Brown grounds are much higher, in the order of 300 Pelicans (Risebrough, Gress, Anderson and ppm or higher (Berger er of., this issue). Schreiber, unpublished manuscript). The cor- The ten Peregrine samples analysed in the present study contained 17.9 12.3 ppm DDE, 0.23 0.34 ppm p,p'-DDD. 0.71 r 0.68 ppm p,p'-DDT, 18.8 12.5 ppm total DDT (DDE -)- p,p'-DDD -)- p,p'-DDT), and 52.2 32.3 relation coefficient between the DDE and PCB concentrations is frequently highly significant. These observations have suggested that the ratios observed reflect the local fallout pattern of the DDT and PCB compounds, and that the ppm PCB. Seven samplea were analysed for DDE and PCB show similar patterns of accu dieldrin, which averaged 0.40 0.64 ppm. mulation, concentration and excretion in Ihe All residues are expressed on an extractable birds and possibly other members of the ecosys- lipid basis, with the 95% confidence limits of tern. the standard error of the mean. The values for Among the 10 Peregrinesamples analysed, p,p'-DDD and p.p'-DDT are lower than those PCB was more abundant than DDE by appreviously reported by WARF, Inc., presum- proximately three times. The correlation CO- , I 1 \ '< j 1 1 I ! I , I I i | , j I I t , j | ; i , i [ ! I I j j | i | , I ' wnini) imiiiiiiw. .mu i i RONS 0977 77. . H4 the 69). hose iCRItl lipid RI'. . 1.2 non iling it at the and ilnd The Inet Mhe 'm to 4 in ound Hllng 'll in s in ogy. .the ellcl the itaco ittal trai at., itely end eor- 7CB the tern . the ecuthe ye- ted, P00- 1970 Risebrough ev. al.: Pollutants in Peregrines and Merlins 251 cilicicnt is 0.8H97, which is significant at the 0.001 level. Allhough it is not known from which urea of the Arctic these birds have come, the results suggest that over n considerable area of the lumlra ecosystems occupied by the Pere grines. this ratio reflects the local fallout pattern of DDE and PCB. The four adult Merlins averaged 302 ppm DDE (139-704) in the lipid fraction. This value may be compared with an average concentra tion of 392 ppm in the lipid of 9 breeding Peregrines from the Mackenzie River region (Enderson and Berger, 1968), 72S ppm jn the fat of four adult Peregrines from Alaska (Cade el al., 1968) and 334 ppm in the lipid of 9 adult Peregrines from Ungava (Berger el of., this issue). Merlins therefore may possess al most the same level of contamination as the Peregrines and might therefore be expected to show symptoms of shell thinning. The concen trations of total DDT in the adult Merlins averaged 314 ppm. 96% of the DDT residues in these Merlins therefore consisted of DDE. The PCB concentrations averaged 196 ppm (44-467). The samples were not analysed for dieldrin. In the three immatures, DDE averaged 49.3 ppm (10.8, 18.6 and 119.3), total DDT aver aged S0.3 ppm, and PCB averaged 28.6 ppm (3.7,29.0 and 51.2). With the exception of one immature Merlin that contained 18.6 ppm DDE and 51.2 ppm PCB, a ratio similar to that found in the Peregrines, all other Merlins contained more DDE than PCB. With the one immature excepted, PCB was significantly correlated with DDE (r= 0.9820, p less than 0.001, four degrees of freedom). Most of the Merlins, therefore, appear to be coming from a region of the boreal forest where the pollutant fallout pattern is different from that in the tundra ecosystem occupied by the Peregrine. When PCB was found to be present in Pere grines, occasionally in high concentrations, it seemed likely that these pollutants were con tributing to the reproductive failures associated with population decline (Risebrough et al., 1968). The dominant symptom of reproductive failures of the Peregrines in Britain has been shell thinning associated with egg breakage, disappearance of the eggs, and eating of the eggs by the adult birds (Ralcliflc, 1970). In the Ungava population of Peregrines in the eastern Arctic, shell thinning and egg breakage arc now contributing to reproductive failures (Berger el at., this issue). The evidence available to date suggests, however, that PCB is not a cause of the shell thinning observed in many populations of birds. No correlation between thinning and PCB was found in the eggs of the White Pelican (Pelecanus rrylhrorhynchos) (Anderson ft al., 1969) or in eggs of the Great Blue Heron (Ardea herodias) (Vermeer and Reynolds, 1970). An analysis of approximately 200 eggs of the Brown Pelican from both eastern and western North America has shown that DDE rather than PCB is associated with the shell thinning (Risebrough, Cress, Anderson and Schreiber, unpublished ms.) Whenever corre lations between PCB and shell thinning have been observed, as in Double-Crested Cormor ants (Phalacrocarax aurilus), PCB is also cor related with DDE (Anderson et at., 1969). Peakail (1970) has reported that p,p'-DDT delays egg laying in the Ringdove (Strepiopelia risorla) and (hat the delay is associated with lower concentrations of estradiol in the blood eatly in the breeding cycle. Peakail had earlier reported (in Risebrough el al., 1968) that technical DDT, p,p'-DDE, and PCB induce the synthesis of liver enzymes that degrade estradiol, and that PCB is a more potent enzyme inducer than is DDE. Delayed breeding may therefore be one of the environmental effects of PCB, an effect that could be critical to Arctic-breeding birds which must complete their reproductive cycle within a restricted period of time. A recent investigation in Japan of the "Yusho" or Rice Oil Disease has traced the cause to rice oil contaminated by chlorinated biphenyls (Kauuki, 1969). Both the contamin ated rice oil and the Japanese commercial PCB produce symptoms when fed to chicks similar to those observed in the "chick edema" syn drome (Goto el al., 1969). This disease of chicks was first observed in the United States in 1937, and among the symptoms were accu- MQNS 097773 252 The Canadian Field-Naturalist Vol. 84 mutation of fluid in the pericardial sac and in the abdominal cavity, subcutaneous edema, and liver and kidney damage (Vcrrctl, 1970). Chlorinated dibcnzo-p-dioxins have been shown to be one of the groups of chlorinated synthetic compounds (hat produce this disease (Higgin botham ct. at., 1968). These compounds have also been shown to be present in the herbicide 2,4,5-T and induce both mortality and embry onic deformities in chicks at very low concen trations (Vcrretl, 1970). A similar group of compounds, the chlorinated dibenzofurans, are Im<M us toxic (Schulz, 1970). These resemble the chlorinated biphenyls in structure and might be derived from them. Whether they are now present in the environment and pose a threat to wildlife promises to be "an absorbing chapter in the research of the immediate future" (Hickey and Rocllc, 1969). Acknowledgements The research was supported by the National Science Foundation grants GB 6362 and GB 11649. , Literature Cited Anderson, D. W., Hickey, J. J,, Kimbrough, R. W., Hughes, D. F., and Christensen, K. B. 1969. Sig nificance of chlorinated hydrocarbon residues to breeding pelicans and cormorants. Canadian FieldNaturalist 63(2): 91-112. Armour, J A. and Burke, J. A. 1970. Method for separating polychlorinated biphenyls from ODT and its analogs. Journal of Ihe Association of Official Analytical Chemists 3.1: 761-768. Bagley, G. E. and Locke, L. N. 1967. The occur rence of lead in tissues of wild birds. Bulletin of Environmental Contamination and Toxicology 2: 297-303. Berger, D. D., Anderson, D. W., Weaver, J. D* Kimbrough, It W. and Reynolds, L M. 1970. Shell thinning in eggs of Ungava Peregrines. Cana dian Field-Naturalist 84(3); 265-267. Cade, T. J., White, C. M* and Hagb, J, R. 1968. Peregrines and pesticides in Alaska. Condor 70: 170-178. Enderson* 7. H. and Berger, D. D. 1968. Chlorin ated hydrocarbon residues in Peregrines and their prey species from northern Canada.' Condor 70: 149-153. Ftmrette, N,, Fyfe, R. W,, and Keith, J. A. 1970. Mercury contamination of Canadian Prairie seed eatera and their avian predators. Canadian FieldNaturalist 84(3): 369-276. Com, M-, SitkiiKuehi, K., and Ogawa, K. 1969. Hydmpcric&rdiiim assay of rice oil which caused Yusho and of Konechlor 400 in Chickens (in Jap anese with English abstract). Fukuoka Acta Medica 60: 5.13.538. Hall, C. If. 1953. Great moments in action: Ihe story of the Sun l.ife Falcons. Mercury Pres*. Montreal (Reprinted in the Canadian Field-Natural ist 84< 3 >: 213-250. Meath, M. CL, Spann, J. W,, and KreUser, I. F. 1969. 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Nature 215: 208-210. JUtdiffe, D. A. 1970. Changes attributable to pesti cides in egg breakage frequency and eggihtil thick- nesa in some British* birds. Journal ot Applied Ecology 7: 67-115. MQNS 09777k . H4 jp* The WH, ural* :ikw ,fcon cstiy .win* Ariel fflCt Icon 1970 Riscdkouck et. al. : Pollutant; in Plhegaines and Merlins 233 Reynolds, L. M. 1969. Polychlorobiphenyl* (PCB'i) atid their interference with pesticide residue analysis. Journal of Environmental Contamination and Toxicology, 4: 128*143. Risebrouflh, K. Reirhe, P., Peakall, D. B., Harman, $. G,, and Klrvan, M. N. 1968. Polychlorinated biphenyl* in the global ecoiyilem. Nature 220: 1098. 1102. Rfcehrough, K. W., Rclrhf, P., and Olcott, H. 8. 1969. Current Progress in the determination of the polychlorinated biphenyls. Bulletin of Environ* mental Contamination and Toxicology. 4; 192*201. ScbuU, K. II. 1970. Clinical. picture and etiology of ehtoracne. Reprinted im Effects of 2,4,5,-T on Man and the Environment. Hearings before the Subcommittee on Energy, Natural Resources, and the Environment of the Comrpittee on Commerce, United States Senate. Serial 91*60. U.5. Govern' ment Printing Office, Washington, D.C. Stanley, R. L. and LeFavocre, II. T. 1965. Rapid digestion and clean*up of animal tissues for pesticide residue analysis. Journal of the Association of Offi cial Analytical Chemists. 48 : 666*667. Vermeer, K. and Reynold*. L. M. 1970. Organo chlorine residue* in aquatic birds in the Canadian Prairie Provinces. Canadian Fild*Naluralist #4: 117*130. Verrett, J. 1970. Statement before the Subcom mittee on Energy, Natural Resources, and the Environment. In: Effects of 2,4,}*T on Men and the Environment. Serial 91*60. U.S. Government Print* ing Office, Washington, D.C. Received October, 1970 Accepted October, 1970 Ver. >961. leltd Min. pro* in of t to *64. lad, rom her Ilea. and t in and 26* inm the itin end Me Iht sti* ek* .led ! i ' * :/ I i j [ t ' > ; ' ! ! 1 i : ' ; . N0NS 097775