Document KJyVvYNMgn7m0qKE1ZLV31Rr2

i 1 lg-/4 pqidvilinn of DOG umi I'oIveIiloriiiaU-cl Ilipltciiyls in Onlvtl Scdimvntii of (lie Santa llnrbarn Hasin Core 265 02M2*N: I2C02'\V. 595 m) was selected for ihc chlorinated hydrocarbon study. It was obtained with a box corer, designed to operate Abstract. Analysis of dated oceanic sediments bom the Santa barbaia basin with the ship's wire slackened and lo r>f the Southern California bight hnt shown that deposition of polychlorinated penetrate slowly into the sediment. The biphenyl* f PC'fl) begun ii/'imt 19-4$ IU</ Pint DDL | t.i-<ti(hlurt>-2-2-bi\(\'-chlvt<>` closing anus of the corer were directly plten)l)ethvlene\ first appeared in sediments deposited about 1952. Conccntra- than of both i/ion- a progressive increase through estimated deposition ratei (in grunts per square meter pet yrari in 1967 of DDL and PCD were 1.9 X 10"* and IJ X 10 K respectively. all.iclied to the collecting box. allowing a tight seal amt minimizing disturbance during rccoveiy and handling. Upon retrieval, the box and core were quick ly frozen And placed in cold storage. I Kauminntion of tinted marine sedi reduction in__their residues as .input Later the frozen eoic was extruded and ments deposited in basins of the south decreases. cut into longitudinal slabs from winch ern California coastal zone has shown The varied anaerobic sediments of x-radiographs were obtained. These t ih.it iIk* present (lux of both lend and the Santa ll.ub.ira Basin present an radioyiaphs were u.ed lo construct I mcrcniy into the sediments exceeds opportunity to determine the rale of varve patient template* which allowed I lh.it of the I9H century. In the Santa deposition of these chlorinated hydro ihc sectioning of the frozen slabs into I llaih.iia Basin, west of Santa Barbara carbons in the sediments within ;m hulk suhsamplvs leprcvmtative of n i ami s.'titlic.ist of Point Conception, the absolute lime framework. The lamina specific .set of years. The slab analysed n<liin|ioiit'M<c lead dux is estimated to tions observed in the sediment arc a was cut from the centra! part of ilv. he twice (hut deriving from natural direct response to the seasonal rainfall core and sectioned, and snbsamrks sources. The inciease of the mercury of the southern California region. The were stored in -lass jars, sealed with flux into the Santa Unibaia Basin began low oxygen content of the bottom wa aluminum foil, both of which had hern about 1900; the present anthropogenic ters of the basin excludes burrowing thoroughly washed with Acetone known input is estimated to be equivalent to organisms and permits the preservation to he free of contaminating substances. I litc natural input (/). Roth lead and of the fine sediment structure. The ac The frozen sample were further mercury arc rapidly precipitated into curacy of the overall time framework chilled with liquid nitrogen and freeze- sediments upon entry to (Ito marine en derived by the counting of the varves dried with a Vir lis lyopbilizer over a vironment from rivers or waste-water litis been confirmed bv the correspon minimum pviiml of 12 hours. A stilv- outfalls (2, .1), In oceanic areas remote dence of rainfall and sedimentation pat sample of approximate*' l.\ g was from these outlalls. a significant hut as yet undetermined fraction of the flus into the basin sediments is assumed to ients (7) nml by -"'pb and --'Th/'-^Th radiometric age measurements (ft. 9). Soxhlct-cxlractcd with 500 ml i f Nano grade {Mitllmkiodl) liosai.o fur 14 derive from aerial fallout (/, /). We report here on the deposition of iwo croups of synthetic orpanochlurincs . Orpanoctikirinc concentration* (pans pci billion (ppb) of the dry wrifllul in dated in the sediments of (tie Santa Barbara Basin. Doth the DDT (5) compounds, principally /i.p'-DDK (.5), and (lie poly chlorinated biphenyls fl'CBl have be come significant components of the m..rinc food webs of i.euihcrn Cali fornia. It has been found ih.il DDI' IHVtl I VOS 1411 Dry weight analyzed (8) 2 61 2.72 1M p.p'-DDI: (Pl*b) P.g'-DDD (ppb) eri pm (<tvy vvii*.bt unat>/nl) (ppb) fieqncMly constitutes more than 0.1 IV2S 2.13 -m percent of the fat of fish-eating birds 1*27 2.61 -no such ns the brown pelican (Pelertttvts IV10 2.59 7\ peeidentaUx) umi of sen lions (/.ulophus ralifornutntts). Hotli DDL' and PC'll arc associated with a high incidence of premature births among these sea lions, and DDL. iicemmis for most if not alt of the in creased variance in the calcium car bonate content of the thus shells of 1912 JVJ5 1917 2.55 2,67 2.64 2.61 2.5* 2.66 (iroiip II e-2.ft --'2.5 '1.0 fi'irmp (. (niaip I) eggs of the fish-eating hints (6). I he I high conci'tUtaliiMis of both DIM: and PCIl encountered in these and other marine ecosystems suggest that the rates of degradation in the marine en vironment are slow; however, depusi- 1955 1957 I von Cioup !'. 24 2.62 It. 2.72 47 lion in the sediment:; provides a prilTi- 2.65 way TnTTTu: return .il TT iTTe>c iW>HiTtrmis H'oin the marine biomass and for the \.V. K MINT 1974 HONS 082^80 if" if- s * IVM Me-M N rob It)) tt0 NM It60 Utt Fig. I. Deposition of (A) DDE and (11) PCD in duleJ sediments of the Simla Bar ham Basin, hours. A 10.2'Cm column of Fiorisil of these compounds to the environment (U j), Incuhulcd at 70Q*C for 5 hours (II). Me:onrjhte amounts of DDE ap to remove compounds producing inter* pear only in the sediments deposited (trlng peak*. topped by 2.5 cm of on* after 1952. We Attribute the higher hydrous sodium sulfate, was used for DDM concentrations in the 1950 sam eiennop. Chlorinated hydrocarbons were ple to spurious contamination during eluted with 200 mi of 6 percent diethyl collection, storage, or analysis. Neither ether (Nnnogrndc) in n-faxAnc. Vol DDK nor PCD shows nnv mqprxrmn umes were reduced to 10 mi or less -hp4 a leveling off in ^ of with a three-ball Snyder column for lion up through 1967. analysis by gas-liquid chromatography. Koidc ct til. (X) estimate from -'"Pb Blank* consisting of 500 ml of n-hexane dating a deposition rate of 0.59 cm/ were refluxed in the Soxhlct apparatus year, in Agreement with the stratigraph for a minimum of 14 hours and then ic estimates of 0.4 cm/year. The mass carried through ail subsequent steps. of dry sediment per cubic centimeter These contained less than the equiva of deposition wax determined to be lent of 5 parts per billion (ppb) of DDE 0.5 g. The 1967 DDE concentrations and 50 ppb of ECU in a 2.5-g sample. of 160 ppb is therefore equivalent to a Concentrations of 10 ppb of DDI; and deposition rale of (160 X 10-") times 50 ppb of PCD were assumed to repre (0.5 g per cubic centimeter of deposit) sent the background within the an limes (0.59 ent/year) times (10* cm2/ alytical procedure. Since PCD has a m-) m T9 X 10 * 8 m-a year-*. The lower electron-capture response than rate of>CB deposition during the same an equivalent mast of DDE. samples tinwr Ihlcrvnl U 1.2 X 10~* g were combined after analysis for the year1. These figures may be as- DDT compounds to determine PCD sumerf to be minimum estimates concentrations, according to the group of the fluxes of these compounds ings in Table ). into the overlying writers. The Dux The profile of the PCD peaks re- of //.//-DDE + />,//-DDD, both of which KmUciI mm ol Arcelor )?M. which may derive from p.p'-DDT. is approxi was used as a reference standard, iticn- mately twice the Atmospheric fallout tiftentmn of p.p'-DDD tl) was con rale of the DDT compounds in precipi firmed on the basis of the disappearance tation over Britain during the period of the peak with saponification (10) and from August 1966 to July l%7 (12). the appearance of a peak with tin* The mean concentration of DDT com characteristic retention lime of (he cth pounds (//.//'-DDL -f- //.//-DDT + />,//- ylcnc derivative. //.//-DDMU (5). ODD) in rnmiull at seven collecting The results of the analyses arc pre stations in Britain of KU parts per IIP-, sented in Table f and in Fig. I. Con assuming an annual rainfall of 100 cm. version of these concentrations, which is equivalent to a deposition of K x arc expressed on a dry weight basis, 10 g nr - year- >. From global pro to an aluminum basis to correct for duction figures it is known that this the salt content in the interstitial water value must be considered a maximum of surface sediments shows no devia estimate of ihc (lux of DDT com tion from the curves depicted in Fig. I. pounds into oceanic systems from the Die deposition of PCD began about almosplictc (12). Local sources for 19-15, following the rapid increase in most of ihc DDT compounds in the PCII Use during World War II as elec Santa Barbara Basin are therefore sug trical insulating fluids, as paint addi gested. tives, and in u variety of miscellaneous The mcasmed deposition rate of Applications which result in I tie release DDT compounds in 1967. if tvnical of other areas In the Southern California Bight, would represent a total deposi tion of 10 metric tons per year over an area 200 km by 200 km. This figure greatly exceeds the estimate of 2 metric Ions of DDI' compounds entering San Francisco Bay from the drainage wa ters of the principal agricultural areas of California in 1967 (N). The esti mated yearly input of DDT compounds from the atmosphere ihio the Southern California Bight in 1971--1972. after cessation of most DDT use in Cali fornia. was 2 metric tons (.?). The rates of atmospheric fallout during the mid1960s, when local use of DDT was extensive, may have been several times higher. Substantially higher concentrations of DDI' compounds are present in sedi ments adjuccnt to the outfall of the Los Angeles County Sanitation Dis tricts* municipal waste-water treatment plant (.?). Input to the sea from that source in 1971 amounted to 19 metric tons (J). A subsurface current, mov ing northward from the Los Angeles area at a depth of approximately 200 m through the Channel Islands (/5), might therefore also be a source of the DDT compounds in the Santa Barbara Basin sediments. The annual inputs of PCB into the Southern California Bight from waste water oullnlls and"from sun ace runoff in 1970-1971 have been estimated to be 10 and^.is mgtric tons. rcspec7ivc- !)- Waste-water treatment plants in the I n* Aiypte%--Orm^Bc County Basin pro vided most of this FCB f.ll. ' N The high rale of local input of both DDI' and PCM compounds into the waters of Ihc .Southern California Bight precludes extrapolation to other oceanic areas. Some recycling of chlorinated hydrocarbons from sediments into bot tom-feeding organisms can be expected (16). hut the concentrations reported in the Santa Barbara Basin suggest that u substantial portion of the chlori nated hydrocarbons entering lire sea from diverse sources is being deposited in the sediments. Wll.SON i|OM'\ HoiM.Kl W. klSMHtOUtill Hutlepu Aforitu l.iilitHtitory, University of Calijotnia, !*.(). Ifo.x 2-17. lUnleKa Huy l Anoavav SimtMt Scripps Imtitutioii of Oceanography, Lit Jolla, California 920.17 Davhi K. Voi'Nrj Southern Califuiiiiu CouMtil Bunt Hesetoeh f'toject, 1200 i.a\t Imperial Hn'hwnv it Sepinuh/ 602-12 11 Vlt MONS 082281 SCIttNCI:. VOJ. HI ' RtftNm m4 Nm I D. R. Yowl. I. M. JoAnwm. A. Soirtat. i. D. Immco. Ninw ItamrU 244. 212 (It22i; T. J. Oww, K. W. Rutland, K. Brrline. A. Stut ter. M, KoMr. E. D. CoWhw*. Si-tmrr III. SSI 0*1)). 2. D. II. Kktfl Wt4 ft. O. notChcr*. En\irem. .Sri. Terhnol. 4 MS 0*70); K. K. TutrUan. in iMfinirwrMf of M** " Oeeam. D, W. Hood, lid. (Wlkr-lnirtwtrncT. Ntw Yoik. 1*21), p. 9. I, Tht Et+btr / tire Southern Cahfoenla Bight: ImpUrmUmt ft* Water (fnmtkr Management (Sotfhrm CaMliwnta CnaM.il Water Rrhcarrti Prnkrt. IMX) Eatf Imperial HiRfcway. Eil Sr- KiaAi. I*2). . V. Wetoa, M. Knide. F.. D. Golilbfr*. Setrnee 1*4. M) <l**li: M. Munvuml. T. J. Qmiw, C. C. PaJimna. frM-Atai. Cawnwcium. Aria 2). I24S 0*6*1. I. A*brc*latlnni: DDT, l,l.1-trlrM'm2.2'W*<r- ftilotophenyhrthafw: p.p-ODF^ i.l-dirhlom- S,t<M*(p`Clilnrophra)i:rtliykne; p.r-tlUD, l.ldlfli)orp-2.J-W0*H'llninphrnyl>f.hane: p.pDDMU, l-ehlivr<>-2.2-niM/-."h)nf*irl>cn>l)fihjl- nc. 4, K. W. llltrbuH'Fti. In PrutTf4/ni An Sixth Bttktlry of thr Muihematteal Sta- Hulca and VtohahiUit. I.. M. L* Cum, 2. Ney- man, U. L. Scott, l.dv (Uni*, of California Freti, Brikclcy and I.n* Anprtci. 1*12). p. 44); K. L. Del-onp. W. 0 Cilmanm. J. O. Slmpion, Sttenct Ml. IIW (t*77). 2. A. Smilar anti J. I>. twines. Oeyn Comm. Hoti. Mar. nth Serf. tilth tittti. II. 257 (1*74). I. M. KnMr, A. SoMar. B. I). Goidb*t. Earth titanel. Sri. I.rti. 14. 442 (1*72). *. M. KoMc. K. W. Bruland. K. I>, Ooldhcrg, Croilim. Ctnntochlm. At-to J), 1171 <19751; S. Krlihtmw.imi. B. S. Amin. I). Lai. A. Sout.it, l.itututl. Oerunttgr. It, 7M (|*75), 10. It. W. NlMrbrouph. P. Kciche. )l. 5. OictMt, Bull, Entlruu. Couiomi. riiil. 4, 192 (I960). 11. M. C. RroadhuiM. Environ. Health I'ertpeei. 2. II (1*72). 12. K. R. Tillf.int and ). 0*0. Tatton. Nature (Lonti.l 21*. 72) <I*6K>. I). E, D. Golilbciy. I*. Butler, F. Meier. O. Menrel. G. Fatilik. R. W. Rischmuph. ).. I . Stickel. Chlorinated tivdrocailHint in the Marine Environment (National Academy i<( Science*, Waxhlnaton. D.C.. 1971). 14. R. W. Hisebrouph. R. J. Muppctt. I. I. Griffin, B. O. Goldtxrp, StUtuf IS*. 12)7 (IW.tt): T E. Bailey and J. R. Ilnnnum, J. Sank. Eng. t)h. Am. Sot. Chit Eng. *.1. 27 (1967). 15. I. If. Joitrc. (icnrrmt emulation ami Water Choratierhtiet In thr Southern California flight (Southern California Coastal Water Research Project. El Sepumht. 1*10. 16. D. R. Niimnn, f*. D. Wilson. R. R. Blackman, A. J. Wilson. Jr., Nature tlumil.tiM, 51) (1971). 17. Supported by NSF pram 0X02*1*5 to the Bodega Marine Laboratory am) NSI: prant GA-27306 to Scrimps Institution of Oeennopra. ptiy and by the Southern California Coastal Water Rrsenrrb Ptojerl (Contribution No. Ift>. Present addrew: Department of OsTaoogrnpliy. University, of Washinpton. Seattle **)*. 50 January 1974 Curvature Detectors in Human Vision? s. McCollough (/) showed that a strik- is adapted to the opposite condition. Bib aftereffect was produced by adapta- The McCollough effect is. in factytye- llonHor several mfiuiics 10 a vertical cific to retinal locus (.?, 4). Now; with graling\of block and orange stripes gaze at the center of the ten-pattern allcrnallnfrvwiih s horlzomal grating of (Fig. ID), concave-up lines appear black and Mbc stripes. Ulack and while pink due to adaptation ty green lines lest gratings wUb retinal orientations of positive slope to thy'right of gar.c similar to those wjthe adapting pat and negative slope lo/fhc left of gaze. terns were tinged wHk colors opposite Similarly, concavcylown lines appear to the adapting eolors\Shc ascribed green. The experiments I describe here these efTccls to "color adaptation of show that this Xypoihcsis accounts for orientation-specific cdfcc-dcicciftrs.'' Riggs' obscrvfllions. Riggs (2) has observed similar cf- High-cfyslrast adapting patterns (Fig. fc..rl.s. with _pa_t_te_r_n_s_o__f_c_u_r_v_e_di iii;nc.sX^Fci;g,,. IA j wcjt projected from the rear on a I, A and U, shows his stimuli. Tt\c diOuMifg screen in magenta light (Wrat- observer views tines that arc concavc\ tcn/.Ma Alter) and green light (Wraitcn up in green light and lines that arc filter). Ihese colors (4) produce concave down in red light, always keep- /vh<y strong McCollough effects. The ing his gaze near the center of cactr pattern (Fig. I A). The test pattern ' (Fig. ID) then appears pink on/con- caveup lines and green on concavedown tines. Adaptation tc/ weakly curved lines produces aftereffects that arc most vivid on pattcrut with sharper curvature. Riggs postulate* curvature detectors, which prefer strong curva ture. y McCollough/simpler idea (the oricntvd-line hypothesis) can explain these effect*. While looking at the ccnicr of the adapting patterns, the rciina to the right of gaze is exposed to green tines of positive slope and red lines of nega tive slope; tile retina to (he left of gaze Fig. 1. (Aj Adapting puttcfvs viewed in mugcnia light tnd gteen ligliiVl'hcse pat(cun hitvc a i.ulitts of curviilul^ of 4.5* when the patterns sublcml uKiul 5.5* across. (IS) Test paitcrn will) n rauiiis of emvature of 4.5", (Courtesy of l\^A. KiDit*! M JUNU |*T4 MGNS 0&4'2d4' mean luminance was approximately J*|0 nitUiJuntbcrl.v The lest p.ilicrns wdre high-contrast prints viewed in while fluorescent room light. All pal- icrn\ were about 5.5* wide, at were RiggsV j ThrVe observer* adapted for 20 min utes lo\hc concave-up pattern inr green and the Voncavc-down one in magenta; the patterns were interchanged every 10 secondAThe observer scanned up and down me vertical midlin^ of each pattern. Witmgaze at the ccrner of the test pattern \(Fig, ID), aoncave-up lines appeared oink and concave-down lines green. Hut, with gaze about \ * beyond the left or right edge, the colors definitely reversed-- concave-up lino* now appeared green and concave-down lines pink. Riggs observed that the col ors did not reverie when gaze was moved somewhat oil the midliitc. The oricnicd-linc hypolhisik predicts that (he colors will appcniVwcaker as gaze moves off the midlincAhut the clearest color reversal will occur only when gaze falls about 1 * iwyond the edges of Ihc pattern. No nbvcrital is expected even when gaze it*/ as much as 1.3* from the midlinc. Tiic concave-up lines will still predominantly Stimulate re gions to the right of gaze with line* of positive slope ana regions) to the tefi of gaze with line* of negative slope, and the concavcidown line* will have the opposite cfljcl. (These \ properties may be seen bv sliding a (racing of Fig. IA across Fig. IB.) \ Riggs observed that each p.ind of the lest pallcr/i (concavc-up or con cave-down lines) appeared pink or green IhroughAut. This spread of color along contour/ within each panel, espe cially to the nnrizonlal tangents of the curves, rcflet/is a general property of the McC\M()Ugh effect (4), and dors not support /the curvature detector hy pothesis in particular, contrar^ to Riggs' argument. I Truly rtirvatiirc-spccilic adaptation was not observed here. Three observers adapted tor 20 minutes us described above while fixating n single point on a horizonljtt train of lighted poum ijt.u moved leftward across the adapting patternj at approximately 1.5* per sec ond. lire irain subtended 20* centered on each pattern, and the observer trucked rcpculcdly from far riglu to far left. Two other observers adapted for ,i hour to the opposite color ton dilion, and Ihc pallcrm were inter changed between each track from tiplM to left. No aftereffects were seen, livery IIV*