Document baxaME577rzybvq8xKnNdee13

NATURE. VOL. 220. DECEMBER 1*:. 1900 Polychlor inated Biphenyls in the Globa! Ecosystem by R. W. RISEBROUGH P. RIECHE . institute of Marine Pvesourccs, University of California, Berkeley 9-1720 D. B. PEAKALL Division of Ecology and Sysiematlcs, Corneil University, Ithaca, New York 14750 S. G. HERMAN Department of Zoology, University of California, Davis 956!6 M. N. KIRYEN San Diego Natural History Museum, PO Box 1390, San Diego, California 92112 Polychlorinated biphenyls arc widely dis persed in the global ecosystem, and are powerful inducers ofhepaticeri7.yir.es which degrade oestradiol. Together with other chlorinated biocides, such as DDT, they could account for a large part of the aberration in calcium meta bolism which has been observed in many species of birds since the Second World War. I DecijnTkg populations of raptorial and fish-eating birds iti Great Britain1 and North Amorioa* have producod thin-shellcd eggs sinco tho period after tho Second World War. A widespread chango in tho chemical environment which affected tho calcium physiology of theso species evidently occurred at that timo. Tho chlorinated hydro carbons, which camo into general uso in tho 1040s, may now be the most abundant synthetic pollutants present in the global environment3. Thin eggshells have been found only in species which, accumulate) high concen trations of those compounds: relatively uncontaminated populations of theso species continue to produco normal eggs1-5. . Calcium metabolism in birds is intimately related to reproductive metabolism and is to a largo extent regulated by steroids such as oestrogen and vitamin Dh Tho deposition of medullary bouo, tho chief source of calcium during egg cud eggshell formation, is controlled by tho steroid sox hormones'-7, and hens deficiont in vitamin D lay eggs with lower eggshell weights8. Steroids aro hydroxylated and thereby degraded in vivo and in vitro by hepatic enzymes induced by exogenous, lipitl-solublo substances, including tho chlorinated hydrocarbons5-11. Tho relatively small amounts of chlorinated hydro carbons required to produco this effect3'11'15-'3, and tho discovery that small amounts of some of tho DDT compounds are oestrogenic3'13'", have mado irrelevant much of the parts per million approach to pollutant ecology based on toxicity data alono. In both Great Britain51-31 and North America33 it was tho decline of tho poregrino falcon which initiated concern about tho extent of tho harmful effects of environmental contamination. In tho United States tho eastern popu lation was extinct before competent observers wore ewaro of a general, widespread decline35. Brooding peregrines persist in apparently normal numbers in British Columbia38 and in tho Arctic37'38. In 1907 we collected an unhatched, abandoned egg of a peregrino falcon in south-western North America, where a 6ma.ll remnant population remains (unpublished work of M. N. K., Pv. W. It. and S. G. II.). Analysis of this egg (Table 1) showed that it contained almost o mg of p.p'-DDN (dich!oro-2,2-tw(p-chiorophcnyl) othylono). Unknown peaks present in tho chromatograms of the extract of tho egg were unidentified until polychlorinated biphenyls (l'CU) were detected in European wildlife33-31. Positive confirmation of the identification was accom plished by mass spectrometry in Sweden3'1. Tho retention times of the unknown peaks in the poregrino extracts proved to bo identical with tiioso of sovoral PCB com pounds on DC-200 and QF-l columns3 and on a mixed V/f-30 1 column. Other species of birds and fish were subsequently analysed for PCB. The chlorine content of several extracts and standards was determined with a Dohniiau microooulometric detector and a method of quantification of tho PCB compounds was devised based on peak heights produced in the electron.capture detector related to standard DDE3. The DDT compounds am destroyed by nitration33 niul p,//-DDT (1,1,1-tricbloro- 2,2-&js(j>-chlorophenyl)cthauo), DDD (l,l-dichloro-2,2-bt> (p-chlorophenyl)othane) and toxapbeno aro dohydrocblorinated by saponification with alcoholic KOH. PCB is not degraded by either procedure. Table 1. cucosixatsd nvur.ocAr.noss ik south Americas rrr.scr.i.si: EALCOXS Per Sample Dieidrin Total centage PCB DDT / DDT* DDE PCB 1. Unmatched 1 Baja California (wet) 0-11 102 87 10*2 10 2. Second year $ mistant front Arctic Breast nui sole (v.et) N'M 99 81 28 3*5 Breast muscle (dry) SDG 81 Brain (wet) NM 85 88 21 t*7 Carcass (wet) Carcass (lipid) 0-S7 02-5 70 5,000 83 19*7 1,420 3*5 3. Immature, California Breast muscle (wet) NM 14*4 80 9*4 1*5 Llver (wet) XM 7-7 92 4*5 1*7 Brain (wet) Brain (lipid) 0-04 0-50 2-8 3G 89 1*5 19-3 1*9 Carcass (wet) Oil 20*2 82 10*8 1*0 Carcass (lipid) 1-0 300 160 4. Adult, California!] Breast muscle (wet) N.M 127 87 98 1*3 Liver (wet) N.M 77 60 ` 57 . 1*4 Brain (wet) 0-31 49*5 80 34*0 1*4 Brain (lipid) 3-7 505 415 Carcass (wet) 1-7 65 87 05 1*3 . Carcass (lipi-l) 50 2.C00 1,930 5. Immature*; migrant from Arctic Breast muscle (wet) N.M 2*3 81 0-16 14 Breast muscle (dry) 7*8 - 0-54 Llver.(wct) N.M 1*0 92 0*10 10 llralu (wet) N.M 0-13 63 0*037 12 - Body fat (wet) N.M 50*3 82 3*2 1C Carcass (wet) 0-07 0*3 82 0*80 12 CarcaM (lipid) 0-14 03*7 5*5 fl. Immature Arctic migrant* * Breast muscle (wet) N.M 1*9 89 0*6 3*4 Breast muscle (dry) G*0 1*9 Concentrations !n parts per million wot weight, dry weight- or liplil weight. * DDT residues Include.: p.ji'-DDT, jup'-DDB, p.p'-DDD (p.p'-TDD), p,pt'-CDhDloMriUna, toe.dp'h-DydDrTocaanrbdoon,pc'o-DntDenDt.s NM. >'ot of the egg measured. were: 4,700 pg p.p'-DDB; 40 pg o.p'-DDU; 20 ;ig P,P'-DI>T; 7-4 pg p.p'-DDD; 37 pg ;).j>'-DDMlr; 5 pg tli-ldrin; 12 pg hcptnchlor epoxide. Concentrations wer- ca!cu'..it. d by assuming a volume of 47-3 ml., the average value obtained by measuring eleven clutches of peregrine eggs from California in the Museum of Vertebrate Zoology, University of California, Berkeley, and by assuming a density of DO. t Second year female, captured in October on tile Texas coast during migration. Died in captivity shortly afterwards, no apparent cans- ofd-ath. No body fat. Total body content of chlorinated hydrocarbons; 33 mg DD L', 10 mg I'Cli, 0-41 mg dicldrin, 0-18 mg liepiaohlor epoxide. Total body lipid. 7 g. Blunngo characteristics of both 3 and 4 were intermediate between those of typically resident California birds and the Arctic race l\untrin.<, .as described by White". No. 3 was an immature female of the year trapped in tho southern San Urancisro l'.ay area in the winter of t Odd. Observed feeding in the area for a week before capture. Died suddenly after eating a dead gull. Moderate body fat. Total body chlorinated hydrocarbon content: 13 mg DDT, tl-8 mg TCC, 0-07 mg dicldrin. 0-U9 mg heptaebiur epoxide. Total body lipid, 43 g. t! Adult fern lie. Trapped in the southern San Francisco Bay area in the whiter of D.iikh Observed feeding in the area for a month before capture. Died shortly afterwards with no apparent cause of death and no bo ty fat. Total body chlorinated hydrocarbon content: 52 mg Dili', 40 mg l'OB, 1-0 mg dieidrin, DO mg h-ptuchlnr epoxide. Total body lipid. 20 g. I, first year female trapp-d on the Texas coast in October, host .at Tt Mugu, Cnlifurnin. the following January ami was stmt by a sportsman 3 weeks later. Abundant body fat. Total body content: 7 mg DDT. 0-0 mg l'Cli, 0*05 mg dieidrin, 0-17 mu heptarldnr epoxide. Total body lipid, 110 u. First year female trapp-d on the Texas coast in October. Died sla-rtly afterwards of heat prostration. In Table 1 aro presented tho results of anolysos of poregrino falcons which died from a variety of causoa ; i DSW 201137 Vr STLCOPCB4059201 . j ;oo NATURE. VuL. 220, DECEMBER 14. 1963 Table 3. ret) and put in the ci.oh.il ecosystem Specks White crapplo (1) Black cmnnlc (2) Bh'.esill(3) Adelie penguin (4) Eggs Western grebe (5) Breast muscle ` Fulmar (G) A 11 C Vink-footed shearwater (7) Sooty shearwater (8) B C' Slendei-bIHed shearvoter (0) Ashy petrel (10) Brown pelican (11) Eggs, Panama Eggs, Baja California Frigate-bird (12)cggs, Panama Brown booby (13) eggs, Panama " * ~ Brandt's cormorant (14) eggs Pelagic cormorant (15) eggs Cinnamon teal (10) White-tailed kite (17) Eggs, clutch A Vnhatchcd egg 11 Unhatched egg C Clutch D Clutch K Clutch F Cooper's hawk (IS) Cclden eagle (19) egg Osprey (20), Baja California Merlin (21) American kestrel (22) Whylr* hody, n.'hilt Eggs, twy diitcli'.s Black-crownu.I night heron (23) >E-gSSg Western gull (21) Eggs,San Trandsco . Kay.tl iroc clutches Lpgs, Far.dlonls.. ten clutches 17' 10 0`S) Total ])DT (p.p.m.) 1-83 (V) 2-10 OV) 5-5 OV) 0-78 (0-39-1-01) 0-128 (L) 20-4 (IV) 10.475 2.000 0-41 OV) 3-4 <\V) 17-5 (\V) 3-0 (\V> 1,205 12-3 OV) 10-3 (\V) 2-3 (IV) 32-0 OV) 2.158 (1,611-2,820) 69-3 (\V) 59 (18-183) 53 (17-50) 0 0. 8-7, 30 0 11-5 (L) 10-0 (L) 29-S (10-4-24-5) 320 8-2 (L) 128 (125-130) 4,310 10-0 (W) 11-4 (9-8-12*0) 5-1 5-3 8-3/ec:4 10-2/egg 31-0/egg 8.500 150 127 (30-204) 435 0-76 OV) 0-34 OV) 0-35 OV) 9-0 (I,) 25-20V) 2-0 (\V) 65 (I,) 2-9 OV) 5-1 .2-4/egg 0-014 0-20 (W) 511 809 803 (032-1,123) 412+ 102 Percentage J>1)E 6 6 6 74 0'S) -- --- -- PCD <0-041 pg/c-gg (p.p.m.) 0-001 (AV) 0-003 0-C05 5-- 70 _ 89 -- G ' 8,000 03 277 04 -- 8G -- 85 KM . 02 -- 5 . 889 (293-482) 61 (47-78) . 81 88 23 1 (18-30) 10-4 (o-o-n-7) 6-4, 5-7, 84-0 89 12-2 (G-5-18-9) 1 113 0 . 62 1 (48-75) 70 -- ` 77 . 6-4 (G-5-7-8) 82 i 0*84 73 3-0 82 4-3/eps 57 4-0/ess 60 ! 3-S/ecs 90 .-- 93 17-5 83 (7-3, 3*0, 103) (24, 7-0, 19) 1 55-4 39 : 3-7 93 PO/ci'g - 0-093 (W) 0-03 (VO) 0-34 ('.V) 0-5 (\V) 0-42 OV) 1-2 OV) 0-9 <\V) 2-1 OV) 8-8 OV) l-- ~ 4*8 <L) -- 0*01 .-- __ __ .-- ._ .-- 6-3 0-23 (\V) --- 0-39 (W) 0-031 0-00 (W) 89 330 09 i 23 85 805 (5S9-1.310) 89 , 136 i 55 -- --' -- BDT.TCB 475 CGij 1,200 >18 270 5 10 2-7 7-2 10 12 15 5-5 1-55 <0 97-3 2) 6-5. 4-0 M, 1-5,0-4 1-7 2-9 2*1 12 P8 60 1-5 2-0 2-G 8-5 4-0 8-5 8-5.10-1, 1-3, 11-2, 9-7.11-1 12-7 1-4 2-3 1-G 36 1*0 3-0 Kggs. Baja Calif, seven clutches 335+ 230 ` 07 45 30 -- 9-1,10-5, 5-0, 12-3,10-6, Forster's ter:: (25) eggs Ca3pi.ui tern (2G) 605 (508-732) 89 114 (91-137) 107.10-5 5-8 Eggs, San Francisco liny Eggs, San Diego Bay Bed piiaiarope (27) . Common lmirre (23) eggs Cassin's uuldet (20) Ancient mnrreiet (30) KhinoecrcisauV.l-t (31) Mourning dove (32) Barn owl (33) 1,209 (1,210-1,322) 1,430 (901-2,430) 1.945 (932-3,021) 12-0, 33-1 0-78 OV) 151 (L) 6-8 (W) 0-75 2-7 0-10 OV) 89 83 * 79 90 03 90 97 77,93 605 (CCO-950) 1,010 (550-1,600) -- 558 (3G4-1,010) .-- -- :-- Kot detected -- '-- 0-10 45 (M 0-10 015 0-3G -- 1*7 1*4 6 3-5 30 5 8 -- Eggs, one clutch Eggs. nm: clutch Meadowlark (34) 27-7/rgg 143/egg 21-2,418 1-25 OV) 6-0 OV) 0-18, 3-3 OV) 95 6 77,93 ` 10-4/ec2 . 14-4/ei.;s 2-5, 281 0-47 (W) 0 GG (\Y) -- -7 10 8*4,15-9 Content In pg and concentrations in p.p.m. wet weight (tV) or lipid weight (I,). I ntc-ss oth<:rwise specified, analyses were of whole bodies. columns. ` ' - - t were Identlfliid on the basis of rete ntlon times on both QF-1 end 1. 1`OM'irU annularit, 231 g, Clear I.akc, Lake Co., Calif., Mav 1908. ' 2. Pumiirii niijrumar.ulatin, 212 c. Clear Lake, Lake Co.. Calif, Mav 1903. 3. Jspomii mam,chin'-. 229 g, Clear Lake, Lake C'o., Calif. May lilOS. 4. 1`i/jn-irrim.'.-hue, Cap-.- Crozier, Ant.-iretiea, October 1907. . 5. Arehmi,ph,,nii orrbUidalix. Clear fake, fake: Co., Calif, .May 1908. 6. Pid.-a.-tM.-v tj'.nrinUt, A and B: Monterey Day, Calif, November 1, 1900. C: Folnt Keyes, Calif, December 1907. Fulmars breed in Alaska. 7. /I'JTiii't, Breeds in Chile. Collected in May 1908, in the Onlf of California. , 8. I'nijinm c/rjseifv. breeds ir, New Zealand and Chile. .4 ami ]!: Monterey Day. November 1, 1000. C: Culf of California. May 1903. NM, Not measured, interO-ring peaks. J 0. fkrfi/m* t,:iwiri,,trU. Dreeds In Australia. Monterw Dav, December 1900 '' 10. ib-t nnr,jfima hann.rl.uM. Farullnn Islands. Calif, May 1903. 11- oeee/eotn.'M. Panama eggs were collected on Isla Paeheea ami Isla TarhcqtiHla. Culf of Panama. February 1908. One eg: contained O-tJ P-lJ.ni. dicldrin and 0-0o p.p.m. ci.drin, another contained 0 16 p.p.m. di'-idrin and 0-07 :*.p.m. endrin (lipid weight). Ilaja Cediioruia eevs were ....... .. at Bahia no Ins Ana-l.-s, March 190s. One egg contained 0-24 p.p.m. dieldrin and 1-13 p.p.m. endrin (lipid weight). 12. h.:j,i!n ,,:,ij,!,/;,(,!. Ida PuclicCa. Panama. l-Vbruarv 19GS. 1- * 1,,. Au/a L-ae.,t.-r. Isla Paeln-ea and Isla Pacti.-.iuilln, Panama. February 190S. Two eggs were analysed for dk-ldriu and endrin. Dieldrin: 0-03. ,, r./*', s endrin: 0-00 and Old 1 p.p.m. (lipid weight). 14. /hal.vt'jrurui j'.-ninUntn.i. Earallon l.siawl-i May 1907 1.7. Fh'ihirrorr.rur firhi-ttrn*. San Mat'-o Co,, CaMf. * 10. Artu rv'U'upt.-nt. San l)ic"o, April 190s. Adult male. .` : 1*. FhtpH-i UtL-n,tt< A ; ('iiidra Co-ta f'n.. Calif., April 1U0H. JJ arul C: Contra Costa Co., May 19CS. two and three.ynuns raf?cd, rospectivrly. V: Aharu.nTt. il. ( omra Costa Co., May 1907. 11 ami F\ Destroyed nest*. Contra Costa Co., March 1`JCS. DSW 201138 STLCOPCB4059202 I :I > i i 1*4 3. M 9. '3. 0-3 5 ICO .cl ;?a 03. D: NATURE, VOL. 220. DECEMFrR M. 196S 1 301 Tablo 3 {continued) is. Ir.-ipi.Vr ir.njn-rii. I'.all".n I'arfc. San llirp'. liV\ l\inrn11a. 1r1 y> 1993. jF'liir.-si,t yiie_.allr ificiinii'Ualai,, utilieudj uoif 1ir1lcm_n< ;owr..iia./iiili.>'.iis>l.s:i.. I ft. * San I.uis OW.-j") Co., Calif.., .AApprirlil1...0..5..5.........U...p..h..a...t.c..h...c..J....c..^..:.:..in nes't wl'toro ilir lilrin.' 1-9 ;ig nf la'ptaolilor Imt no rmlriti. one j'uun^ . was raibc.l. ]'c.; olio conUiincJ -i-T /i~ of s*. /nia'ioii hnUntliu. Cuir of California, March lOaS. _Onc czz also contained 0-10 p.p.m. dieklrin and 0-2.7 p.p.in. endrin (L). ei. /',:AvciiltailcrKi. Immature, Utah, Dcci'!iil'.'t 19u7. 0.1 Ft: V.i s wivriii*. Adult was hilled on road, Mendocino Co., Calif., IVcemhcr 1997. F-ks from Davis, California, 1903. tz. V'/rtirornj- i'i<-'knr'ai. Fees from did'ermt clutch,'3, San Francisco Day, May 1007. "A. ihriK n-rit,V;:fIi. Standard errors, 9.7 per cent confidence limits. ' y.':ur.jt,r.i, n. San Piezo Day. May 1907. lhii"'Prv}rj n.ipia, 1907. * /Ari/nraptu fvtknrrjs. Monterey Day. Fovember 1, 19C0. r.Viu on.'i/f. Farallnn Islands. May lfli". 2ft. :o. I't'/chifrtwphii* a!-'utini(i. FataHon Is.anus, April 1. uG. Frn.miUjTdwpltn nntkii"in. Monterey Day, November 1,lOuO. m. Ctt<.r!.\r.ra T-.r.mc'ratn. Monterey Day, November 1. 1000. 32. Tt'rmi'hira wr.rro'irc*. Sail Diego, .Inly 1903. 33. Tvt" ntha Clutch A from Contra Costa Co., Calif,, Match 1935. 3*. Fttini'lla r.riWIa. Davis, Calif., December 1937. Clutch li from Yolo Co.. Calif., April 10G8. In these, however, the amount of DDT was very low; species of raptors do not accumulate high amounts of with a DDT:PCB ratio of IS, no PCB would hnvo been tha organo-chlorine compounds (Table 3), a result of the detected. A larger amount of fat material from Antarctic very low residuo lovels usually found in their prey. organisms, which would contain moro DDT, would American kestrels and barn owls arc common residents of therefore have to be analysed beforo concluding that PCB California cities. The white-tailed kite, which was has not yet reached the Antarctic. near extinction 40 years ago in California, is now abundant Individuals of species resident in industrial areas have, in areas where insecticide use is intense, yet because it m expected, higher PCB levels than individuals of the preys primarily upon tho short-lived and herbivorous same species from more remote regions. Analysis of vole, Microlws, the species accumulates very little DDT 1,-11 eggs from ten clutches of the western gull from the or PCB (Table 3). Fiirnlkm Islands showed an average PCB content of Previous work38 lias shown that both DDT and dieklrin 13ti55 ug (95 per cent confidence level). PCB content induco hepatic enzymes in tho pigeon which, in an in of four eggs from three clutches from an island in San vitro preparation, increaso tho metabolism of progesterone Francisco Bay averaged S05 pg with a range from 5S0 and testosterone. This work has now boon extended to > 1,310 (Table 3). Seven eggs from soven clutches in study the metabolism of ocstradiol by enzymes induced (lie Gulf of California contained 4530 p.g of PCB. by p.p'-DDE, technical DDT (Dupont) and PCB (`Aroclor The DDT content of the eggs from the Farallons was not 12G2'). The experimental procedure previously described13 significantly different from that of the Baja California was followed except that the chlorinated hydrocarbons eggs. were injected intramuscularly ratiicr than given orally, Birds from the Gulf of California also contain dieklrin and in the separation of ocstradiol and its metabolites ami enrhin (Tables 2 and 3), but the number of analyse the solvent system used was the upper layer of a mixture is us yet insufficient to compare their relative abundance of benzene:heptane: methanol: water 7:3: S: 2. The strips with that- of DDT and PCB. Despite the inability of the were monitored with an autographic strip scantier. The Shell Chemical Company to find any chlorinated hydrocar profiles obtained for the various inducing agents are bons in the. Gulf of California and at the mouth of the shown in Fig. 1. It will be noted that the profiles of the Colorado River35, which drains into the Gulf, it is likely metabolites obtained after enzyme induction using DDE that some do enter from the Colorado River and from and DDT are identical, but that a different metabolite agricultural areas in western Mexico. A significant ' is produced by tho enzyme induced by PCB. The amount fraction, however, must come from the atmosphere36, of metabolites formed was calculated from the radio anti air transport best explains the presence of PCB in activity of the peaks. The results obtained are given in remote areas. In extracts from the Gulf of California Tablo 4. one PCB compound ivas present in relatively small concentrations. This compound is readily degraded by ultraviolet light irradiation in laboratory experiments, and may therefore be selectively degraded in the atmosphere. Although PCB is not soluble in water, it lias a low but finite vapour pressure33. Incineration of materials containing PCB would greatly increase the rate of entry into the atmosphere. PCB is used in the manufacture of many industrial products, so the high amounts found in San Francisco Bay, Puget Sound3 and San Diego Bay presumably result from direct discharge Table 4. INCREASE or OHSTKADIOL 1! ETA HOLISM BY NGEOX LIVER HOMO GENATES FROM MUDS TREATED WITH VARIOl'S CHLORINATE1) IIVDROCARHO.VS Control DDK (40 mg/kg) DDT (40 mg/kg) PCB (20 mg/kg) Amount of polar metabolites formed in m/'molcs 20-3 6*3 ?5*2 13*1 ic9o3-*o1i1o1*r*>2 Each figure is the average with standard deviation of a croup of four birds. In nil eases 500 m/miolcs of o*`5tradiol-0,7-T (500 inCi/mm'/Ic) was present in the incubation mixture. Incubation time 30 min, weight of microsomal fraction ua-.d 300 mg. All chlorinated hydrocarbon# were injected intramuscularly into the pectoral muscle 7 days before d^ath. of industrial wastes into theso waters and from local fallout. Body concentrations of 40 p.p.m. of p,p'-DDE signifi The presenco of PCB in the few land birds and fresh cantly increased the rate of ocstradiol degradation by water fish analysed indicates that it is also distributed tho induced enzymes in the experimental conditions. among continental ecosystems in North America. Pere On a weight basis tho PCB preparation had an ocstradiol grines could therefore acquire PCB, as well as the other degrading potential approximately fivt> times that of chlorinated hydrocarbons, over all their global range. p,p'-DDE or technical DDT. Both DDE anti PCB, No PCB residue data arc available for prey species from which are apparently tho most abundant of the chlorinated (he Atlantic, but compounds which seem to bo PCB hydrocarbon pollutants in tho global ecosystem, have have been isolated from seals33. A second year male therefore tho capacity to produce sublethal physiological peregTino spent, the winter of 1067-GS on Isla Pacheca, effects in birds. Panama, where the peliean, booby and frigate-bird eggs of Studies on tho activity of induced enzymes in the rat Table 3 were collected. The Cooper's hawk which was at various times after a single injection of DDT or analysed, a species which also preys upon birds, contained dieldrin havo been made by Ghnzal ct aI.3*. lie found high residues of both DDT and PCB (Tablo 3). Cooper's that it took 70 days for the activity to fall to half its hawks have declined in eastern North America and in maximum value in tho ease of DDT and 15 days in the some regions havo produced th,in-shelled eggs31. Several caso of dieklrin. Experiments with dieldrin on pigeons siv 201139 STLCOPCB4059203 1 102 NATURE. . ... 220. DECEMBER 14. 1DGC This work was supported- by the US National Scu'ium Foundation, the Bureau of Sport Fisheries and Wildlife and tho US Public Health Service. Pure p.yj'-DDK was supplied by tho Federal Drug Administration, and saniufes of `Aroelor' by tho Monsanto Chemical Company. Received August 20; revised Xovcmbcr 14,1003. 4 KatciifiV, D. A., Kr.lurt.Z15, 203 (1007). Hickey, J. J,, and Aiuler.-on, D. W., Science, 102, 271 (1003). Kisebrough, K. V"., In Chcmical Fallout, First FochcsUr Confercr.cc on Toxicity (in the pro's, 1003). 4 Simkiss, 1C., Calcium in Feproductiie Fhyciulo'jy (Rtinhoid, Xe-.v York, 1907). Simkiss, K., Fiol. F,ei\, 30, 321 (1001). .. Clavcrt, J., and llenoit, J.. CR Sac. Riot.. ru.-is.T30, 503 (1942). 4 Kyes, P.. and J'otter, T. S., ,4nnf. Fee., 60, 377 (1931). Hart, K. B,, Stocnboek, II., Lcpkovsky, S,, Kictr.icii. S. \V. 1'.. llalpln, J. G., and Johnson, O. X., J. Jliol. Chun., 65. 579 (1925). Welch, R. M., Levin, W,, and Conney, A. H., Chemical Fallout, Fire1 r.ochrtfcr Conference on Toiicily (in the press). Hart, L. 0., Sclmitice. It. W., and Fonts. J. B,, Toxicol. Appl. FI,amatol.. 5, 371 (1903). 11 Ilart, L. G., and Fonts, J. It., Fautiyn-Schmiedebcry's Arch. F.ip. Pc.lh. Pharniakol.,2',9. 450 (19`35). Conney. A. H., Welch. R. XL, Kuntzman, It., and Burns, J. J., Clin Pharmacol. Thcrap., 8, 2 (1900). > Conney. A. H.. Pharmacol. P.ec.,10, 317 (1907). 14 Knpfcr, D.. Residue Fee., 19. 11 (1907). 11 Gerhoth. G., and Sclnvabe, U., Arch. Pip. Pathol. Pharmalco!., 240. 409 (1904). Gillett, J. W,, J. Ayric. Pood Chcm.,16, 293 (1903). ' Schtvabe, U.. Arzncim.lltcl-Forsch.,li, 1205 (1904). 41 Peakaii, J. It.. Xn'we.215, 595 (1907). * Weleli, It, M,, Levin, W-, and Conney, A. II., Toxicol Appl. Pharmacol. (In Fig. l'. Chromatographic separation of oee'.rndiol anil Us metabolites. The large peak Is unaltered oestradiol. tlie prc=3). " Bitunn, J., Cecil, H. C.. Harris, S. J., and Fries. G. F,, Science, 1G2, 371 (1903). 41 Ratcliffc, H. A., Frit. Flrdsfbl, 23 (193S). show that only a quarter of maximum activity remains 44 llatclifie, 13. A.. P.ird Study,11. 50 (1903). after a month. Tlius there is cviclcnco that the effects of these induced enzymes can persist over a long period of time although more studies are needed to determine the steroid degrading potentials of livers of those species 11 ltatcliRe, D. A.. Fird Study, 12, CO (1905). Itr.tchfre, I). A., Fird Study. 14, 233 (1907). _ 11 Hickey. J. J., Peregrin: Falcon Populations: Their Fioloyy end Fecline (University of Wisconsin Tress, in the rress). 44 Beebe, F. L., Condor, 61, 1-15 (1900). contaminated with chlorinated hydrocarbons. The ' Cade, T. J.,White, C.:H,, and Ilauah.V.Tt.'Contfor/IO/TTO (190?). profile of the metabolites should be some indication of the history of exposure to chlorinated hydrocarbons. . The reductions in eggshell thickness and eggshell weight increase the chances of egg breakage11-24, and 1! Hriderson, J. IT., and Berrarfll.111..fCordor,[7 0,[149 tl'003). 41 Jensen. S,, Pen- Sc!., 321012 (1906). Witlmark, G., J. AssocJOff. Anal. Chcm.,[50,11009 (1907). _ 11 Holmes, I). C., Simmons, J. II., and Tatto.n, J. 0*G., Future, 216. 22. (1907). _ water retention, which affects hutching success40-41, might bo impaired. The environment in which birds now exist is therefore no longer tho same as that in which 41 Hrro, F., Revenue,rA., and Becianan, H.. Full. Environ. Cord. Toxicol.. 372 (1907). 44 White, C. XL, Auk, SS. 170 (19GS). Jefferies, 13. J., and Brest'., I., Frit. Finds, 59. 49 (1900). they evolved; it is unlikely that any species lias the genetic capacity to meet the selection pressures resulting from the abrupt environmental chango which has produced the thin eggshells. The peregrine falcon is a species 44 Al'Jrin. DiclJrin, Endrin (A Status Feport) (The Shell Chemical Company. 1907). 44 Riscbrough, R. W.. Hnrcet, R. J.. Griffin, J. J.. and GoMbenj, F.'I4.. Scicnce.lbO, 1253(10 03). . 44 Tech. Full. PF-390 (Monsanto Chemical Company). long highly revered and respected. G. H. Thayer45 has described it as "the embodiment of noble rapacity and lonely freedom". An irony therefore exists in the fact that tho peregrine may be the first species to bo extirpated 44 Holden, A. Y., and Ilursden, K., Future, 216, 1274 (1907). ' 44 Ghazni, A., Koranskv, XV., Port's, J., Yohiar-.d, H.LW., and Klcmpau, I.. Arch. Exp. PathoL Phuruiakot., 249, 1 (1904). 44 Jones, R. F.,, nml Leopold, A. S.. J. IVildl. Uanajement, 37, 221 (1907). 44 Mayhem,'\V. W,, J. Veildl. Mana-jeracnt.lZ. 30 (1955). by global contamination. 44 Thayer, G'H., Fird Lore. 6. 47 (1901). Tsunamis on the Moon? by W. G. VAN DORN Scripps Institution of Oceanography. University of California, San Diego, California . i The spacing of the five annular mountain rings around Mare Orientals fas a dispersion curve for gravity waves on a 50 km "liquid" layer overlying a rigid basement. Thh question whether tho multiple ring-like mountain structures surrounding most of tho lunar craters larger thnn 120 miles in diameter might bo "frozen tsunamis", sot in motion by the shock wavc3 caused by impacting plauetcsimals, was first brought to my (attention by IB B. Baldwin (personal communication). Baldwin points out that in several cases (including the giant Mare Imbriiim) two or more rings can be made out DSW 201140 STLCOPCB4059204