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Organochlorine Pollutants in Peregrines and Merlins Migrating through Wisconsin Robert W. Risebrouoh Department of Nutritional Sciences Imtitute of Mat ine Rctouroet University of California Berkeley, Califo nia 94720 * Gregory L. "lorant Laboratory of OrniiMccy. Cornell University, lihac*. New York Daniel D. Birger 1)21 N. Jelfenoi Milwaukee. Winomia 3)202 , . * - ' - The diicovery that the Peregrines (Falco pere- ern Canada (Hall, this issue), the United Stairs trlnut) breeding in Hie eastern Arctic are laying (Hic';ey and Anderson, 1968) and Great thin-thclled eg >s and are ihowing symptoms of Britain (Ratdiffe, 1970). reproductive failure (Berger et a/., this issue) At the conference convened in Madison. suggests that tliis population is beginning to be Wisconsin, by J. J. Hickey in 1963 to examine - affected by tha same extinction process that the ci uses of disappearance of the Peregrine hat resulted in the extirpation of breeding Pere from the eastern United Stales, ail conceivable grines in man/ areas of North America and factors were considered in detail. Among these, Europe (Hickey,1969; Ratdiffe, 1970). The only environmental pollution was consistent Peregrines of the eastern United Slates disap with the pattern of extinction observed in peared before the nature of the extinction pro Peregrine populations in both Europe and cess was evident, but subsequent research North Ameitea (Hickey, 1969). Since repro showed that eggshell thinning had been asso ductive failure now appears to threaten the ciated with the population decline (Hickey and survival of the Arctic populations, it has be Anderson, 1968). In Great Britain there was come imperative to determine more precisely a considerable amount of evidence that exces- the particular pollutants responsible. . slve mortality of adult birds had been a major In addition to the evidence rdating excessive reason for the rapid decline that began around adult mortality to the use of several of the mote 1935, coinciding with the introduction of highly toxic of the chlorinated hydrocarbon imecti- toxic insecticides such as dieldrin into agricul ridej, Ratdiffe (1970) has accumulated a con tural use (Ratdiffe, 1963; Jefferies and Prestt, siderable amount of data relating the shell 1966). The surviving birds, however, exper thinning among British birds of prey to the ienced reproductive failures that were charac environmental distribution of orgsnochlorine terised by (hell thinning, egg breakage, and eat pollutants, induding both insecticides with thdr ing of the eggs by the adult birdt (Ratdiffe. derivatives and compound. The 1967; Ratdiffe, 1970). Although embryonic latter consist primarily 6f polychlorinated mortality may be contributing to the decline in _biphenyls which have become widespread end reproductive oapadty of the Ungava Peregrines "locally abundant pollutants (Jensen et at., (Berger el at., this issue) the pattern of egg 1969; Koeman et til., 1969; Risebrough et at., breakage associated with shell thinning now 1968). Other pollutants that might be contribu observed in this population appears to be iden ting to the decline of the North American tical to the symptoms noted previously in south- Peregrines include mercury and lead. Mercury 247 MUNS 085146 241 The Canadian Field-Na tuaalist Vol. *4 b more widespread in the environment than months old. Seven were biopsied in 1968 and ' was previously suspected (Fimrcite el (., this three in 1969. All of the Merlin samples were issue). Waterfowl may accumulate lead from obtained in 1969. Three were adult males, one 1 ingested shotgun pellets (Baglcy and Locke, an adult female, and the remaining three were 1967) and Peregrines preying upon them might inimatures 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 .he birds in any way. Biopsy samples lating, however, that one or more of the chlor have been obtained from Harriers (Cfmr inated hydrocarbons, particularly the DOT cyaneus) that have been observed for many ' compound DDE, may induce shell thinning months afterwards (Frances Hamcrstrom, per - under both emfronmental and experimental sonal communication). conditions (Hickey and Anderson, 1968; Porter The. adipose tissue biopsy samples were , and Wiemeyer, 1969; Heath er of., 1969; frozen, either hi acetone-washed glass vials Anderson el of., 1969). Very small concentra capped with aluminum foil, or in sterile packets tions of DDE i re 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 (Pelecarus occidentalii) (Risebrough,. samples were weighed in the laboratory to ob ' 'Anderson and Srhreiber, 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. Liphb 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 vet solvents were removed by evaporation. When unclear. Delayec 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 rate 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; Pcakall, 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 Roeile "How much industrial pollutants like 0.3608 gm. Some samples were found to consist the polychlorinated biphenyb have alto contri mainly of connective tissue rather than lipid. buted to tome 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 Roeile, 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 chlorinated 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 Felco cotumbarhu) 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 Materials and Methods 1 Davidow column (Stanley and LeFavoure, 1965). This column, consisting of edits, sul _ ' All of the Peregrines were immature birds of furic acid and fuming sulfurie add, permits the year and therefore approximately three rapid cleanup with quantitative mcov- MQNS 065147 rfijiu m * ? 5 fc l3 9511531 m i u 1970 R/stROUCM BT. ai .r Pot mutants in PrnrcKiNKs and Merlins 249 , erics of the DDT compounds ;>n<l PCB . ' Although not an important factor for the present study, it permits much larger amounts . of lipid material to be treated at one time tlvm ' . docs the flonsil method. This procedure, how ever destroys dietdrin and to determine this . compound a.iolher method must he employed. . Another aliquot of the lipid extract, in hexane. , was parlitioicd twice with acetonitrile, the combined act lonitrilc fractions were cvnpoi ated to dryness. redissolved in jxjlrolcum ether, and i - applied to a florisil column. The column w:i5 rinsed first with 200 ml of petroleum ether and 200 ml of 6% ethyl ether in petroleum ether. | Dieldrin was eluted by passing 200 ml of 15% j ethyl ether in petroleum ether through the col| umn. Control* had indicated that 90T or more ) of the dieldrir applied to a florisit column eluted in this fraction. Blank samples consisting of redistilled jwtio leum ether analysed through the entire procc- ' dure showed no substances that might interfere with the determination of any of the chlorinated hydrocarbons reported here. . The extracts were analysed with o MiciotcU gas chromatograph equipped with a tritium ami | - a nickel-63 electron capture detector. Glass columns were used containing 3% 01' t. or a | mixture of 3% QF-J and 10% DC-200, on : Chromosorb W, 80-100 mesh, acid washed and HMDS treated. v - Other laboratories (Reynolds, 1969; Aimour and Burke, 1970) have developed methods for . separating the polychlorinated biphenyls fiom ' . some or all of the chlorinated hydrocarbons of insecticide origin. The polychlorinated biphenyl compounds emerge at different times fmm the . gas chromatograph and occasionally a pc.? I. may coincide or interfere with the peak produced ' by one of the insecticides. We have found it . possible, however, to quantify PCB, DDR, p,p'-DDD, p,p'-DDT, dieldrin and ernlrin on the basis of the procedure outlined above, irh- out any attempt at separating the PCB Dieldrin and DDE emerge at exactly the same timi* on the DC-200 column, but on the QF-T column there is no significant interference between dieldrin and DDE, or between dieldrin and any of die polychlorinated biphenyls encountered in environmental samples. DDE frequently con* siiiufcs 90% nr more of the DDT compounds picscnt In wildlife. The electron capture re sponse of DDR is considerably greater than dun of PCB, and although one of the PCB compounds emerges at approximately the same time as DDR, the error introduced in the DDE determination is less than experimental erw even when the total PCB concentration is up to five times that of the DDE. Vermeer and Rey nolds (1970) have commented upon the diiB* culty in separating the DDT compounds p,y DDD and p,p'-DDT from PCB. On the DC-200 column, both DDT compounds emerge at approximately the same lime as a PCB peak (Anderson et al., 1969). On theOF-l column, however, there is no interference between p,/~ DD r and any of the polychlorinated biphen/Is usually encountered in environmental sampler Although many hiph*t y[ compounds arc released ijitojlft qiyifonmc!isr rrfativefy few persist injhe higher levels of fond chains. Moreover, these are*found In appro imafely the same proportions in environmental samples over wide areas of the world. T.ie rfuomafograms of the PCB compounds in the Peregrines analysed in the present study are therefore similar to the chromatograms of Pere grine extracts from Mexico, California, and Amchitfca Inland (Risebrough, unpublished re sults). Moreover, the chromatograms are similar to those obtained from extracts of Brown Pelican egg* from several areas in both North and South America (Risebrough, unpublished results), ft is frequently possible, therefore, to treat the PCB mixture as a single compound and to obtain accurate relative concentrations of PCB using any one of the several peaks. The peak emerging at the same time as p.p'-DDD on the OR-1 column is almost always of the same height as two of the other peaks. It is therefore possible to obtain a crude estimate of the DDD present without initial separation of the PCB. lliis assumption may be tested and the identification of p.p'-DDT and p.p'-DDD con firmed by saponification (Anderson etti., 1969; Risebrough et at., 1969). An aliquot of the I iiMNm.ira.Ww r*wy MONS 085148 . 2S0 :; 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 DDT and DDD to their respective ethylene derivatives, DDE and DDMU, but leaves the PCB profile of the chromatograms unchanged. Since the profile of the PCB peaks was similar, but not identical to the profile observed in chromatograms of the commercial prepara tion Aroclor 1254. PCB was quantified by comparing the total area of the PCB peaks emerging after DDE with the areas of the same peaks 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. Results and Discussion Enderson and Berger (1968) have previously reported on the chlorinated hydrocarbon resi dues found in biopsy fat samples from immature Peregrines that were also trapped during fall migration at Cedar Grove, Wisconsin. These samples, analysed by the Wisconsin Alumni Research Foundation in Madison, Wisconsin, contained an average concentration of 19.4 ppm of DDE on a lipid basis. DDE concentra tions in the fat of females at the Arctic breeding grounds are much higher, in the order of 300 ppm or higher (Berger ef a/., this issue). 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 0.68 ppm p,p'-DDT, 18.8 * 12.3 ppm total DDT (DDE + p.p'-DDD + p.p'-DDT), and 32.2 32.3 ppm PCB. Seven samples were analysed for diddrin, which averaged 0.40 0.64 ppm. All residues are expressed on an extractable lipid basis, with the 93% confidence limits of the standard error of the mean. The values for p,p'-DDD and p.p'-DDT are lower than those previously reported by WARF, Inc., presum ably a result of interference by PCB in the earlier determinations (Anderson er a/., 1969). The dicldrin values are equivalent to those previously reported and there is no significant difTcrence in the DDE concentrations. On a lipid basis, the average values reported by WARF, Inc. were 19.3 ppm DDE, 0,8 ppm DDD, 1.2 ppm p,p'-DDT and 0.3 ppm dicldrin (Enderson and Berger, 1968). First year immature Peregrines migrating from the Arctic have therefore low residues of DDE. Unfortunately little is known about the relationships among dietary levels of DDE and PCB, equilibrium concentrations of these com pounds i.t various tissues, and the times requited 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 or the prey species, ^ajudcnttndillg of the pi armacodynamics of DDE and PCB in birds is nne of the cnnsnlciinm ft-fiejenriee in our knov'ledge in the field of pollution ecology. * Within several ecosystems so far studied, the concentrations of pDE in birds tends to parallel the cone mirations of PCB. The ratio may be approximately one to one, as in San Francisco Bay (Risebrough ef at., 1968). DDE is several times more abundant than PCB in several Pacific marine ecosystems (Risebrough at at., 1968), but in Florida, PCB is approximately three times as abundant as DDE in the Brown Pelicans (Risebrough, Grets, Anderson and Schreibcr, unpublished manuscript). The cor 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 DDE and PCB show similar patterns of accu mulation, concentration and excretion in the birds and possibly other members of the ecosys tem. Among the 10 Peregrine samples analysed, PCB was more abundant than DDE by ap proximately three times. The correlation co HONS 005149 f r t f I T in H Cif^ \i\ 1970 Risebrouoh it. al.: Pollutants in Peregrines and Merlins 25; efficient is 0.8897, which is significant at the shell thinning associated with egg breakage, 0.001 level. Although it is not known from disappearance of the eggs, and eating of the . which area of the Arctic these birds have come, eggs by the adult birds (Raldiffc, 1970). In the .' the results suggest that over a considerable area Ungava population of Peregrines in the eastern of the tundra ecosystems occupied by the Perc- Arctic, shell thinning and egg breakage are now grines, this ratio reflects the local fallout pattern contributing to reproductive failures (Berger el of DDE and PCB. "t- this issue). Thr^rtitlrncr iyiiliWl6 m.jtolf : The four adult Merlins averaged 302 ppm DDE (139-704) in the lipid fraction. This value may be compared with an average concentra- lion 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 era/., 1968} and 334 ppm in the lipid of ' 9 adult Peregrines from Ungava (Berger el at., (PelecanujeiyihmrHynchos) (Anderson el al.. 1969) or In era of the Great Blue Heron (Ardea herodlas) (Vermeer and Reynolds 19701. An analysis of approximatelg^JOOjgi; of ths Brown Pelican from both eastern and this issue). Merlins therefore may possess al western North America has shown |1)ILJ2QE - . most the same level of contamination as the rathe than PCB Is associated with the she!l tninnmg (ffMWpTor^An^im and .. Peregrines and might therefore be expected to show symptoms of shell thinning. The concen- bcnreiocr. unotlbliaaciL-mal.) Whenever cone ' {rations of total DDT in the adult Merlins lations between PCB and thSTthinnlni have . averaged 314 ppm. 96% of the DDT residues been observed, as in UoutHe-CretteTCormor in three Merlins therefore consisted of DDE. ants ' Phatacroearax aurilusl. Pt*T> is U, we. matea with lib* lAnamn. nJ town ' . The PCB concentrations averaged 196 ppm. ' (44-467). The samples were not analysed for Pe tkall (1970) has reported that p.p'-DDT dleldtin. delays egg laying in the Ringdove (Strepiopeiia In the three immatures, DDE averaged 49.3 . ppm (10.8, 18.6 and 119.3). total DDT aver aged 30.3 ppm, and PCB averaged 28.6 ppm (3.7,29.0 and 31.2). With the exception of one immature Merlin thal 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, risorla) and that the delay is associated with lower concentrations of estradiol in the blood early in the breeding cycle. Peakall 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 f mom ~u>Uitn-w-PDBa Delayed breeding mv thgtgfaw be one ofThe environmental rfTeclt at PCft effect that could be critical to Arctic-breeding birds which must complete their reproductive therefore, appear to be coming from a region of cycle within a restricted period of lime. the boreal forest where the pollutant fallout A recent investigation in -limn of the pattern is different from that in the tundra "Yusho" or Rice Oil Disease has traced the ' ecosystem occupied by the Peregrine. cause to Qggjyi contaminated by chlorinated Whan PCB was found to be present in Pete* biphenyls (Katsuki, 1969). Both the contamin , grines, occasionally in high concentrations, it ated rice oil and the Japanese commercial PCB ' seemed likely that these pollutants were con produce symptoms when fed to chicks similar tributing to the reproductive failures associated to those observed in the "chick edema" syn with population decline (Risebrough el al.. drome (Goto el al., 1969). This disease of - 1968). The dominant symptom of reproductive chicks was first observed in the United States failures of the Peregrines in Britain has been in 1957, and among the symptoms were accu- 11 ff!Fan l i HUNS 085150 2S2 The Canadian Field-Naturalist Vol. 14 . mutation of fluid in the pericardial sae and in . the abdominal cavity, subcutaneous edema, and liver and kidney damage (Vcrrett, 1970). Chlorinated dibcnzo-p^jjoxins have been shown to be one of the groups of chlorinated synthetic compounds that produce this disease (Higgin botham et. <rf., 1968). These compounds have ' also been shown to be present in the herbicide jiAtind induce both mortality and embry- onlc deformities in chicks at very low concen trations (Verrctt, 1970). A similar group of compounds, the chlorinated dibenzofiiraits, are almost as 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 Roclle, 1969). Acknowledgements The research was supported by the National - Science Foundation grants GB 6362 and GB 11649. . ., Literature Cited . AMww, D. W, Hkkey, I. J., WuhmaL R. W., Hughes, D. F,, and Christrnwa, R. E. 1969. Sig nificance of chlorinated hydrocarbon residues to ' breedinf pelican* ami cormorant*. Canadian Field- Naturalist 13(2): 91-112. Armour, J. A. and Burhe, 2. A. 1970. Method for separating polychlorinated biphenyls from DDT and Ms analogs. Journal of the Association of Official Analytical Chemists 53: 7*1-761. letfley, G. E> and Loch*, L. N. 19*7. The occurreace of Iced in tissues of wild birds. Bulletin of Environmental Contamination and Toxicology 2: 297-305. Berger, D. D., Anderson, D. W* Weaver, V. D., . . Kimbrough, R. W. and lUynoMs, L. M. 1970. Shell thinning in eggs of Ungava Peregrines. Cana dian Field-Naturalist 14(3): 2*5-267. Cede, T. in White, C. M* and Hough, J. R. 196S. Peregrines and pesticides in Alaska. Condor 70: 170-171. . EadereM, I. H. and Bergar, D. D. 1961. Chlorin- aled hydrocarbon residues In Peregrines and their prey epeties from northern Canada.* Condor 70: 149-153. Flmrefta, R, Fyfe, R. W,, and Keith. J. A. 1970. . Mercury contamination of Canadian Prairie seed eaten mid their avian predators. Canadian Field- Naturalist 14(3): 2*9-27*. , Goto, M* Sahaguchl, K* and Ogawn, K. 19*9. Hydropericardinm assay of rice oil which earned Yusho and of Kanechlor 400 in Chickens An Jap- anew with Baglith abstract). FukuokaActa Medka Mk 533-5)8. Hall. C. II. 1955. Great moments in action: Tie Story of the Sun Life Falconi. Mercury Free*. Montreal (Reprinted in the Canadian Field-Natural1st *4(3): 213-230. Heath, K. G., Spann, J. W* and KreHarr, J. F. I9*n, Maked DDE impairment of Mallard rrprnductio i in r ontrolled studies. Nature 224: 47-41. Hkkey, J. J,, editor. 19*9. Peregrine FiIcm Populations: Their Biology and Decline. University. of Wisconsin Press, Madison. 59* pp. Hlehey, J. J. and Anderson, D. W. 196*. CMorln- ted hydrocarbons and eggshell changes in raptorial and Ash-eaiing birds. Science 1*2: 271-273. Hkke i, J. and Raelle, t. E. 19*9. Conference sunmary and conclusion*, in Peregrine Falcon Populations: Their Biology and Decline, J. J. Hickey, ed. University of Whcbnsia Press, Madkor. pp. SH-W. Hlggh botham, G. 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B. 1970. p.p'-DDT: Effect on calcium metabolism and concentration of estradiol hi tht blood. Science 16*: 592-594. Porter, R. D. and Wkmryer, S. N. 19*9. DkMrin and DDT: Effects on Sparrow Hawk eggshells and reproduction. Science 165: 199-200. Ratcliff*, D. A. 19*3. The status of the Peregrine in Great Britain. Bird Study 10: 56-90. Ratcliff*, D. A. 1967. Deercom in eggshell weight in certain birds of prey. Nature 215: 206-210. Ratcliffe, D. A, 1970. Changes atiributabk So pesti- ' rides in egg breakage frequency and eggshell thick ness in soma British* birds. Journal of Applied Ecology 7: *7-115. 1 ! : ? | * . , J 1 ! | f! j ` 1 | | I t ; I | ( i . ' k / I I I > ! I [ 1 J ; I I V, MGNS 085151 i l l i I it it Hr! H mu h Itl* r-H I t U M ( M i * 'I1.' 1970 Risebrough et. al.: Pollutant^ in Peregrines and Meruni 353 . HijmMi. L. M. 1969. PolychlofoWphenyls (PCB's) United States Senate. Serial 91*60. UJL Govern ' and their interference with pesticide residua analysis. ment Printing Office. Washington. D.C. . Journal of Environmental Contamination and Stanley, It L. and UFavoure, II. T. 1965. Rapid Toxicology. 4: 121*143. digestion and dean*up of animal tissues for pntlcida V RJsrbroogb, R. W., Rekhe, P,, Peahall, D. B Harman, residue analysis. Journal of the Association of Offi \ : l{. $. G* and Kirven, hi. N. 1961. Polychlorinated cial Analytical Chemists. 41: 666*667. biphenyls in the global ecosystem. Nature 220:1091* Vermeer, K. and IteynoMa, U M* 1970. Orgsno- 1102. chlorina residues in aquatic birds in the Canaiflsn Rbebroogh, R. W,, Rekhe, P., and Okott, H. & I'rairk Provinces. Canadian PJeM*Naturalisl 14: . 1969. Current Progress in the determination of . 117*150. . the polychlorinated biphenyls. Bulletin of Environ* Ver-ert, I. 1970. Siatemcnt before the Subavu* . mental Contamination and Toxicology* 4: 192*201. n Ittee on Energy. Natural Resources, and tha I! .: ~, Behai* K. H. 1970. Clinical picture and etiology of chloraene. Reprinttd In: Effects of 2,44*T on Man and the Environment Hearings before the Subcommittee on Energy, Natural Resources, and Environment. In: Effects of 2,44-Ton Mm and the Environment. Serial 91*60. U4. Oovermnent Pm*. irg Office, Washington, DC. Received October, 1970 ' the Environment of tbe.Conupittee on Cemmeroc, Acc spied October, 1970 MOMS 00515^ f