Document B5nn4Vvvy0D6jGq82wdYg3J2j

. ..... tDginvector 8) (2) *iay y w better in water depleted in v.Aygen 18.and deuterium where the numerical coeflicie..iS arc taken from equation rj;. Similarly, the tree-growth anomaly pattern correspond ing to the year following a high percentage of albaeore caught north of San Francisco can -be represented as: While growing oals ai dilTereni temperatures in waicr of ddveieni **0 and deuterium (D) abundances, wc noticed- tint oats grown in Antarctic water in which is depleted in >-o and D by --49%, and -400%,, relative to standard mean ocean water map 6=8.56 (eigenvector 4)-6.17 (eigenvector 9) + 11.54 eigenvector 10) (3) (SMOW used as u comparative reference in hydrogen and oxygen isotope studies), showed initial growth 1-2 weeks sooner than did oats grown in water containing greater uO and D These maps arc presented in Fig. 4. The ring-width data were mostly from trees sited in arid localities, so that a aide ring would generally he associated with anomalously cool, cloudy weather and above normal precipitation whereas a narrow ring would reflect warm, sunny and dry conditions. . Below normal tree growth in the Pacific North-west (big. 4) is indicative of dry conditions associated with below normal cyclonic activity during the fishing season. Sunny and mild weather would favour albacore fishing ' in adjacent waters, as would above normal insolation regard less of weather. The resulting excess of stored heat in the ocean would be given up through evaporation during the following autumn and winter and lead to increased cyclonic activity and precipitation along the coast north of San Francisco. These conditions would lead to increased tree growth during the following growing season (Fig. 4). Autumn and winter climatic anomaly features, com bined with spring dimate and the year-to-year autocorrela tion of tree-ring widths, produce the other ring-width anomaly features in Fig. 4 for the following growing season. Narrow ring widths south of San Francisco, for example, imply below normal precipitation--an expected feature since winter precipitation in the Pacific North-west is negatively correlated with winter precipitation in southern California'. concentrations. The oats seemed to grow better in water which was most depleted in the stable isotopes throughout (he growth period, The oats were grown from the same batch of seeds in two sealed glass-covered glass jars (approximately 10 I). Twentyfive oat seeds were added to each jar, containing the sameamount of vermiculite and 500 ml water to which 5.0 g Etpid. Gro, a commercial fertiliser, had been added. One jar contained melted glacial ice from the Antarctic with isotope concentra lions of -49%6"0 (SMOW) and -400%. 6D (SMOW). The other jar contained distilled ocean water with + 1.0%, 6'*0 (SMOW; and 4 17%. 6D (SMOW). Both jars were placed in the chamber at the same time. ''Theexperiment was repeated three times with new materials: once the growth chamber was maintained between 1.7 and 3.3 C; once between 24 and 26.6'C; and once the temperature fluctuated between 1.7 and 26.6`C. Each time-iheoats in the jar containing water depleted in the heavy isotopes showed germination 1-2 weeks earlier and seemed to grow better throughout the growth period, than oats grown in distilled ocean water. Using oats grown at 15 `C, the first sign of germinal ion "in the jar containing water depleted in the heavy isotopes was 4 d after planting. On the day 6, eight plants (out of 23) had attained a height of 6 cm. The first sign of germination in the jar with water containing the heavier isotope concentration, was after The reconstructed values of albacorc catch distribution data (Fig. 3) and inferred population distribution also seem to exhibit long term changes over intervals of 100 yr or 17 d. By the time five plants had attained a height of 6 cm in this jar, in that with water depleted in the isotopes, 23 plants that had reached the top of the jar (approximately'25 cm). more, which suggest the possibility that long term fluctua Kashutin1 observed that snow-water depleted in D increases tions in the occan-aimosphere system may be involved. the yield of cucumbers, radishes and spring-wheat compared The success of the calibration of tree-rings with albacore with controls grown in ordinary water of unspecified isotopic catch indicates the possibility of relating tree-ring varia composition. He cites experiments on the egg productivity of tions to any type of biological variations which are affected hens and the weight gain of suckling pigs, in both cases water by large scale climatic fluctuations. Such relationships may depleted in D was especially efficient in promoting productivity. be quantified and used to reconstruct objectively other Although much has been done on the effect of D-enriched climatically-caused biotic variations in the past. water on biological systems, we suggest that research on the effect D-deplcted water on plant and animal growth may prove N. E, Clark National Oceanic anti Atmospheric Administration, Natiunut Marine Fisheries Service, Southwest Fisheries Center, fruitful. A major source of water depicted in D by over 400";-, (40%) compared with SMOW is snow and ice from the Antarctic polar plateau. Water depleted by 150-180%, is readily available in the USA from Rocky Mountain snow precipitating above La Jolla, California 92037 10,000 feet elevation. Jim D. Gleason Laboratory of Tree-Ring Research, T. J. Blasiko H. C. Fkitts US Geological Survey, Denver, Colorado 80223 Irving Friujman University of Arizona, Tucson, Arizona 8S721 Received February 10; accepted June I* 1973. I Kt-hulln, K,, rrltoda (t/SSAl SI, 107 (I9A9K K<U<d OfitmtKf 5. 1974; accepted May 6, 1975. < V. C-. IU. IfW.MCWI (1974). * Kami**. Alim. Wrath, Art,, U.5. />*, Agrh., 97. I7J. 192 <l9(rt|. * Lurt. ft. M., rt *i/,, ArtHitt of fsAnt A'WrWn/ Murfnr FUhetirt SrrrUr-Amrtfrun f'sthetttim'i ftrlrunh PuutuUnkm Athwart Slurliet CnaUtutrtf During I9t$ {National Marine Fibltcrlei Service, t'fcheifc* Center, Li Jolla. 4 Clrntcnr, H. P., and Oaff, W. L. CalifDtpt f'iik wut Ctmie, fi*k DhII., )28 * (196?). Soif. O. L-. Col>/. Coot*. Otftfolt dth, Atf*t, 7. tlt-144 (I94A). * IVW. C- (I . .<n tau HtRottn* af tome peenpUutian puUtrot in Culifoihta unit oti/tueM tefton* (Umc(Hy California Water Rcuwm Center, 7946). Identification of chlorinated dibenzofurans in American polychlorinated biphenyls Mortality of embryos has contributed to the reproductive failures of several bird species, including the sparrowlunvks (Areipitrr nisus) of southern Scotland1, the white-tailed eagles (UuUueetus albicitln) of Schleswig Holstein', and the herring n'ev 019294 727349 WATER_PCB-00052544 306 I'.vilU {l.artn aryriitnttii) of Luke Ontario*. Suspected causes include (2,2-/m-(p-chlorophen),l)-l,l-dichloroethy- kne), other chlorinated biocides and/or their derivatives, and the polychlorinated biphenyls (rCHs). all of which are pie-nil as contaminants in the eggs'-5. PCBs are present in high concentrations in the bird populations which suffer embryonic mortality1-*. Other orgunoehlorine compounds which may be present in food webs include the chlorinated dibenzodioxins and the chlorinated dibenzofurans (Fig. 1), which are toxic to embryos in amounts'-' less than 1 pg. They arc therefore among the most toxic substances known and are possible causes of the observed mortality. The chlorinated dibenzodioxins and chlorinated dibenzo- furnns, however, have proved exceedingly difficult to detect in environmental samples in the concentrations at which they arc expected to be cmbryotoxic'-10. The chlorinated diben zodioxins enter the environment as contaminant s in preparations of (he herbicide 2,4,5*T (refs 5 and JJ) and the fungicide pcntachlorophenol1*-1*. Chlorinated dibenzofurans have been found in a French (l'henoclor DP6) and a German fClophen AnOj PCIl and were shown to be the active cmbryotoxic agent in these preparations'. The techniques used, however, did not detect chlorinated dibenzofurans in an American PCB, Aroclor 1260. We report here the presence of chlorinated dibenzofurans in Aroclor PCB, widely used in North America and Great Britain, and in the same Aroclor 1260 preparation examined previously with negative findings'. ' Samples of PCB examined include: Aroclor 1248, J254, and 1260 (1969); Aroclor 1254 (1970); Aroclor 1016 (1972); and die same three preparations studied by Vos ei a/.': Aroclor 1260, lot No. AK-3; Clophen A-60, lot No. 912434; and Phcnoclor DP-6, lot not specified. The latter three PCBs were obtained from Dr Vos, the others from the Monsanto Company in the years indicated in parentheses. PCBs extracted from environmental samples most often have gas chromatographic profiles similar to those of PCB formula tions containing approximately 48, 54 or 60% chlorine. In the Aroclor series, the former two -PCBs are equivalent to Aroclor 1248 and Aroclor 1254, respectively. Aroclor 1260, Phcnoclor DP6, and Clophen A60 all contain approximately 60% chlorine. Chlorinated dibenzofurans were identified in all Aroclor preparations except Aroclor 1016, as well as in Clophen A60 and Phcnoclor DP6. Aroclor 1016 is a PCB mixture containing Fig. 1 Skeletal structures of: o, chlorinated biphenyl, x-y -- 1-10; b, chlorinated dibenzofurans, x-f y - 1-8; c, chlorinated dibcuzcdiuxiiis, x-f-/ = 1-8. Nature Yal. ?S6 July JJ /<j7 <, Inkle 1 Chlorinated dibenzofuian concentrations* in Arovtor _____ Clophen and Phcnoclor ' l'CU Aroclor 1248(1969) Aroclor 1254 (1969) Aroclor 1254 (1970) Aroclor 1260.(1969) Aroclor 1260 (lot. AK3) Aroclor 1016 (1972) Clophen A-60 Phcnoclor DP-6 4-CI 0.5 (25) 0.1 (6) 0.2(13) 0.1 (10) 0.2 (25) ND 1.4 07) 0.7 (5) 5-01 6-Cl 1.2 (60) 0.3 (15) 0.2 02) 1.4 (82) 0.4 (27) 0.9 (6(1) 0.4 (40) 0.5 (50) 0.3 (38) 0.3 (38) NO NO 5.0 (59) 2.2 (26) 10.0 (74) 2.9 (21) 1 otal 20 1.7 15 1.0 08 ._ 8.4 13.6 Expressed as pgg*1 PCD. Values in parcnlhcses represent quantity as percentage total dibenzofttran. NO, not delected (<0.00l pg g*1). Amounts of PCB ranging from J.O to 2.0 g were dissolved in 400ml hexane, placed on a florisil column (180 g. internal diameter 31.5 mm), and eluted with: an additional 1,600 ml hexane, and successive 800 ml volumes each of 5% diethyl-cther-hcxanc, 25% dfcthyf-ether-hexanc and acetone, at a race of approximately 7 ml min-'.Themajor portion of the PCB was eluted in the hexane fraction, which was discarded. On addition of the.5% mixture, the eloalcx were ,collccted in-six successive 4(0 ml volumes. To eliminate the polar solvents, each dilate was evaporated twice just to dryness and ijIcii up each time in a minimal amount of hexane. Each fraction, in 1 ml hexane, was placed on a microalumina column" and eluted with 10 ml each of 1 % and 20% methylene chloride in hexane. These were also taken twice just to dryness and made to up a volume of I ml in hexane to eliminate the methylene chloride before gas chromato graphic analysis. Aliquots of all fractions obtained before and after partitioning on alumina were- injected into a six foot glass column containing 3%OVI on 100-120 mesh Supelcoport in Tracor MT220 and Hewlett-Packard 5700 gas chromatographs equipped with "Ni electron-capture detectors. PCBs were found to be present in each fraction eluted from the Florisil column in amounts sufficient to interfere with the detection of trace contaminants. Partitioning on the alumina columns separated most of the PCB interference into the 1 % methylene chloride fractions. On removal of this interference, different peak patterns appeared in the chromatograms of the 20% methylene chloride fractions. Compounds eluting in the 20% methy lene chloride fraction were collected for mass spcctrometric analysis using a 20:1 effluent splitter, and a trap consisting of a capillary tube (I mm internal diameter, 100 mm long) bent to a U shape, immersed in a liquid nitrogen bath. Methylene chloride (20%; 4 pi) in hexane was injected into the capillary as a rinse, removed with a 1.0 pi micropipctte, and placed directly on the mass spectrometer probe. The probe was inserted into a GF.C AEI MSV02 high resolution mass spectrometer and the solvent removed by the force pump. 1 he probe was rapidly inserted inlo the ion source and multiple scans were recorded in the on-line high resolution mode". approximately 42% chlorine and has replaced Aroclor 1242 in many applications, principally as the dielectric fluid in capacitors". Values reported in Table 1 represent the total of those compounds found in 400 ml Florisil fractions 2-6. A total of 10-12 isomers was identified in each PCll. Two chlorin ated dibenzofuran contaminants have been reported for the Clophen and Phenoclor previously*; our first analyses of the Clophen revealed an additional five chlorinated dibenzofurans*. The structures contained four to six chlorine atoms. Other diben zofurans including those chlorinated to a lesser extent may have been present in the first 400 ml fraction but this was not examined in detail as it contained substantial PCB interference. Recently synthesised 2,3,7,8-tetra-, 2,3,4,7,8-pemn- and 2,3,4,6,7.8hcxachlorodibenzofuran were used to quantify tetra-, penta-, and hexachlorodibenzofurans, respectively. The former two authentic standards had retention times on the CAM column the same as those of two dibenzofurans isolated from the PCB Vos et at.1 detected no chlorinated dibenzofurans in an Aroclor 1260 preparation at a detection limit of 1 p.p.m. Fractionation and examination of the identical Aroclor 1260 in our study confirm their findings based on the stated limit, but reveal the presence of 11 chlorinated dibenzofurans in the preparation, having a total concentration of 0.8 jig g ' PC'!! (Table 1). The same workers also found diethyl ether extracts of the Clophen A60 and Phenoclor DP6 to be much more toxic to chick embryos than diethyl ether extracts of Aroclor 1260. Our study confirms those findings on the basis of chloiinaied 727350 WATER PCB-00052545 h'uiurc Vol. 256 July 24 1975 b ,-~'n*7^rJi-vr'x'11 vV ~nT^T--r-^r iT'-t* 4...r'-:i'ii 150 200 250 300 350 Hr. 2 a, Gas chromatogram of a fraction of Aroclor 1254 containing a mixture of chlorinated biphenyls, dibenzofurans, amt naphthalenes. Identities of peaks ore given in the text. 6, Mass spectrum of peak 2, a telrachlorodibcnzofuran. dibenzofuran content: the identical Clophcn and Phenoclor contain It and 17 times more total chlorinated dibenzofurans, respectively, titan the Aroclor 1260. A gHs chromatogram showing components derived from the Aroclor 1254 obtained in 1969 is represented in Fig. 2. The components were eluted in the Second 400 ml Florisil fraction and recoveted front the alumina column in 20% methylene chloridc-hcxanc. Fach of the numbered peaks was trapped as described here, and identified by mass spcctronietric analysis. A nominal mass plot of the high resolution mass spectrum of peak 2 is shown in Fig. 2. lire plot includes all the ions with elemental compositions ranging to the maximum empirical formula C|i(H0MCl,,CI,*Ct. The molecular ion cluster nt nominal m/c 304-310 fragments by successive losses of Cl to yield the ions at m/e 269-275 and CO to the ions at ;/ 241-245. A minor loss of Cl front the peaks at m/e 269 -275 also occurs to yield the ions at mle 234 -238, followed by CO elimination to m/c 206-210. The group of peaks at m/e 152-154 arc the doubly charged molecular tons. An identical spectrum was obtained from an authentic standard of 2,3,7,8-tclrachlorodibenzofurnn. Thb latter compound has a retention time identical to that of peak 4. Peak 2 is, therefore, a positional isomer. The nccuratc mass measurements for the characteristic ions are within 2 p.p.m. oftlic calculated exact masses. Peaks identified on this chromato gram and their retention limes relative todieldrin areas follows: h mixture of ictra- and pcntachlorobiphcnyl (1.02); tctrachloro- dibenzofuran (1.30); pcntachlorobiphcnyl (1.46); tctrachlorodi- hctmifurnn (1.57); hcxachloronaphthulcnc (1.75); penta- clilorcbiphcnyl (1.86); hcxachloronaphthalcnc (2.00); and licptaclilnronaplitlialcitc (3.46). An aliquot of combined fractions derived from the same Aroclor 1254 was treated with diuzontcthanc to assess whether any chlorinated orlhu-ltydroxy- biphenyls (pre-furans) were present. Cas chromatographic analysis of the sample before mul after ticatmenl resulted in identical chromatograms. As large quantities of PCBs have entered the global environ ment1^", it may be assumed that (lie contaminant dibenzofurans 307 also have been released in proportional amounts. Their per sistence, effects, and significance remain to be determined. We thank .1. A. Buikc, M. L. Porter and J. Ci. \'o^ for discussions; A. S. Kende for standards of chlorinated di benzofurans; and F. C. Walls for assistance with the mass spectrometry.. This work' was supported by the Canadian Wildlife Service, National Science Foundation, and NASA. Canadian Wildlife Service, Toxic Chemicals Section, Ottawa, Canada K!A OH3 Gl KALD W. Jlowis* Micum.i, J. Mui.viiiti.u . Space Sciences Laboratory, University of California, Bcrno R. T. StMostn A. L. Burlingame Berkeley, California 94720 Bodega Marine Laboratory, U, W, Risfbkougii ' University of California, Bodega Bay, California 94923 Reserved February t J; empted My 28,1975. flyvent eddrees: CeMfoiniti Weiet Reioutcei Control Board. Hiviiion of Pltnui wl Reveereh, IS16 Ninth Siteet. Sacramento, California 9JII4 Newton, I., end Bofen, J,, .Ventre, 149, *82-583 (1974), Koeman. t. It., HaOdetinth, R. H., and BtjleveW, M. F. J. J., Blot. C'ontrrr.. 4, 777-377(1972). . Gilbertson. M,, and Hale, R.. Cam. FW.Ver.. 91. 734-356 (1974). Iliccinbolhant. O. R., et *1.. S'xtmt. 370, 702-70) (1961). Sparvehu, G. L, Dunn. F. L, and Roe, V. K, FeJ Cumin. Toxit., 9, 40' 412 (1971). Vnt,3,G..Kneman 3. tl,, Vender Meet. )l. L, ten Noever de Breuw, M. C., and de Vot, R. II, FW Comitf. Tusk., I. 62S-6J3 (1970). Vol, J. G,, Binron. Htlh Ptnp., I, lOS-t 1711972). ` Rowei. G. W, Stmoitelt, B. R,, Burlinflmt. A. L, de l erpc, B. W, ami Ritebrouili, R. W,, 6n.lt(.<1. Htlh Cenp..!. 191-198 (1971). Bauchman, R. and Meuluin, M,6nWrwi. Htlh Ptnp.,i. 27-33 (197?). Bauihman. R,,and Mexlken. M, Atlr, dim.. 120, 92-104 (1973). Report on 2.4,S.T (Ettecutke Office ofthe President, Science Advkory Committer, Office of Science end Terhnolocy, Match. 1971). Ictucn, S, and Renbetg. L,, Amble. 1,62-67 (1972). Firestone, D, Ret, J.. Blown, N. L, Barton. R. P., and Damien, 3. N, J. All. Off. Anxtyi, Chtm., SS, 85-92 (19:1,. Potter, M. (-.end Botke. J. A ..J. Att. Of. Axjlyl. Chm.. 54. 1426- 1428 (1971). Burhnramc. A. I... OUen. R. W, and MePhetton, R. Vq-rWr. Mon Spttir., 6. 1033-1059(1974). Nlahel. I. C. T, and Sarof.m. A. F, Fm/ow. Hllh Ptnp.. I, 21-38 (19721. Bowei, G. W, and 3onkel, C.J..J. fhh An. DilCtn. (in the pretv). iettven. S.. JohneH. A. G, Okenn, M, and Oittfliod, G.v/u,,f 224, 247--2S0 (1969). i* Knemait, 3. H,, ten Noe.rr de Brauw, M. C,, and de Vo>, R. H, S'aunt. 221, 1126-1128(1969). re Rltrbrouch, K. W, Kekhr. P,, Peekell, D. B,, Herman, S. G, and Kitven, M. N, Neturr. 220, 1095-1102 (19681. Niche breadth in Bryozoa . as a test of competition theory Competition theory predicts that intraspecific and inter specific competition should often have opposite effects on the use of resources by a population, the former increas ing, the latter decreasing, the range of resource actually used1''. Field data supporting these predictions are well known for the interspecific case''* but arc scarce for the inlraspccific condition, and we have been unable to find any reference demonstrating both effects within a single species. We therefore report here the verification of both predictions In respect or competition for space by the epiphytic hryozoan Alcyonidiutn hirsulum: less extensive data suggesting the same effects within other hryozoans are also reported. ' tniraspccifie competition should result in an increase in the range of a resource spectrum used by a species, as at Itiglt population levels the advantages to any individual of being at the competition-free optimum of a resource gradient arc offset by the intense intraspecific competition found there (Fig. lu); this is the `principle of equal oppor tunity' of MacArthttr'. Interspecific competition, on the other hand, should tend to restrict the range of the resource spectrum used by a species, as individuals attempting to exploit marginal resources cannot do so as efficiently as 727351 NEV 0 1 9 2 9 6 WATER_PCB-00052546