Document 3e698NZYeErEqzjpdqJMx6GYa

innately result in faster metabolic rates. Tne fact that not only surface-born bacteria (/) but also microorganisms collected at (ho deep-sea floor arc ex hibiting extremely slow metabolic rates when incubated in situ may be inter preted in two ways. Life processes in general may be slower at deep-sea conditions than at surface pressures and temperatures for reasons other than the low nutrient supply. Studies on (he deep-sea benthic fauna (7), have reported (i) extreme diversity of species, (ii) small brood sice, (iii) preponderance of adult in dividuals in most species, and (iv) abun dant cases of endemism. These charac teristics suggest slow growth and long life of the individual animal and could be the result of a relative retardation of ixrtam critical metabolic processes. The slow metabolic rate may also lead to the argument that an active, adapted microflora does not exist in the deep-sea sediment. The high colony counts usually found when deep-sea sediment samples ore streaked on nu trient agar (5) may originate solely from surviving and viable cells that reached the ocean floor with sedimenting detri tus particles. Particulate organic nut ter readily available for microbial de composition will hardly reach the deep ocean. It " ill largely be degraded dur ing the slow sedimentation, estimated to take from several weeks to more than a year per 1000 m of depth (5). The particulate organic matter in deep waters was shown to be '`refractory" < 9). tlut is, no degradability could be demonstrated. The total amount of larger paniculate material (for instance, mimal carcasses) reaching the deep sea imdegraded will probably be very small, dthough of considerable significance for :hc highly diverse hut scanty fauna of x-nthi: scavengers. Nothing is known iboul the quuntity of nonrefractory or ganic matter reaching the deep-sea floor *ii)t the relatively fast-sinking fecal pelds of zooplankton (8). t hus, the top sediment being virtuilly void of nonrefractory organic mat er readily available for degradation, he activity of microorganisms in the lei-p sen may be largely confined lo incslinal iracts of animals, where the nrichcd mtlricnt milieu will enable tticronrganisms lo decompose rcfracory materials (chitin. cellulose, and so orth) in an endosyntbintic fashion. This lotion is supported by ihc finding of m enlarged gut in deep-sea mollusks 10), According to this hypothesis, the ole played by microorganisms in the i may m> mrnover of organic matter in the deep- sea sediments appears to be funda mentally different from that in shallowwater sediments, or, for that matter, in soil. Experiments on incubations of solidified organic materials (agar, starch, gelatin) on the dcep-sca floor in open containers {//) show tlmt after l year of exposure, marks of animal feeding appeared to be almost the only sign of disintegration. No work on the intestinal flora of deep-sea invertebrates has yet been done. Complementing our earlier work (/), the data reported in this study conflrm the conclusion that the deep sea must be considered extremely inefficient with respect to recycling of organic wastes. HoLaea W. Jannasch Carl O. Wirsen Woods Hole Oceanographic Institution, Woods Hole. Massachusetts 02543 R*frn<t ud 1. it. VV. Jarauvib, K lerY./iiMv L. I) Wlrvrn, A. FifmjnfarmuUin. Anr...|71, o'2 (1972). 2. O. H. Lowry. N. S. Rovcbroupti, A. L. Frr, R. J. Randall. /. Biol. Chtm. 193, JM (19)1). 3. Iik-niiiictj by R. Tumtr (Museum <( O-npjrj. uva Zooluiy. University). 4. K. L. Smith and J. M. Teat. Scitncr 179, 212 U97J). 5. C. E. ZoRtll. Hull M,,akl Mar. Hint Inn Kyoto Untv. I], 77 (1961). 6. ------ and L. L. Hittle. Can. /. Microbiol. 13, 1311 (1967). 7. J. F. Grassle and H L. Sanded, Detp-Sra Her., in pres*. 8. T. I. Smayda, Ocronntr. Mar. Blot. Anna. Rev. I, 333 (1970). 9. I). W. Mcnrtl and J. II. Kyilicr, Inn. Mar. Sel. Uitiv. Alaiko I'uht. AV I (1970), p. 31. 10. J. A. Allen nod H. L. Saodcn, Dttp+Sta Rts. 13. 117$ (1964). It. H. W. Jannatch And C. O. Wltxn, In prepara tion. 17. Wa thank P. Holme* for atifMance In one of the Alvin dive*; and J. M. Teal, 3. P. Giasato. and K. L. Situ di for a critical dlacmtion of tha manuscript. Research supported by NSF Riant GA 33*05. This la contribution No. 2987 of the Woods Hole Oceanographic Inultutlon. 4 December 1972 a Polychlorobiphenyls in North Atlantic Ocean Water Abstract, Concentrations of polychlorobiphenyls t PCB's) have been measured at the surface and at various depths in the water of the North Atlantic Ocean between 26N and 63N. The concentrations average about 20 parts per trillion and amount to an estimated 2 X 10* metric tons of PCB's in the upper 200 meters of water. The overage concentrations of PCB's in the surface water of the Sargasso Sea are lower than those in the northern North Atlantic. Seawater is the most abundant solvent available for trapping hydrocarbons, such as the polychlorobiphenyls (PCB's), released into the environment. The volume of the oceans (I0*1 liters) is sufficient to dissolve all the PCB's that have been manufactured (/). Relatively few measurements have been made of PCB coocenirations in open-ocean water to- determine the extent to which it functions as a solvent trap (2). Most analyses have been confined to orga nisms (i), which comprise less than l part per million of the total volume. During the summer of 1972 we analyzed the PCB concentrations of open-ocean water in the eastern and western North Atlantic between 26N and 63N. The stations and analyses arc tabulated in Table I (4). For samples i to 9 and 13 we extracted 19 liters of sea water (5) with 2 liters of a hexane-ether mixture (94: 6), concentrated the extract, and then analyzed it by electron cap ture gas chromatography (ECGC). For the other samples wc pumped 19 lo 80 liters of water through a brass or glass column (16 by 2 cm (inside diameter)) packed with Aniberlitc XAD-2 resin(Rohm & Haas) to a height of 12 cm (r>) at 250 ml/min. The PCB's were eluted from (he column with 300 ml of boiling acetonitrile at full gravity flow. The acetonitrile was then diluted with l liter of water (distilled or seuwater) and extracted with hexane. The con centrated hexane extract was analyzed by ECGC. No cleanup of (he extract was required prior to ECGC. Unfiltercd seawater samples collected and analyzed simultaneously with water filtered through a 0.3-,.m glass fiber Alter or a glass wool plug contained a maximum of 10 percent mute PCB titan the filtered seawater samples. All analyses were completed on shipboard within 4 hours of sampling (7). Three observations can he made front the data: 1) Although the range is very broad, the concentrations of PCB's in the northern North Atlantic average 35 ng/kg (35 parts per trillion (ppt)] in surface waters, and 10 ppt at 200 in. 2) The PCB concentrations decrease with depth. 3) The surface waters of the Sar gasso Sea (stations 25-41) have slightly lower surface concentrations of PCB's (27 ppt) than Mirfaec waters in other parts of the North Atlantic. The widespread distribution of PCH\ ft*) 9 9 T 7 0 O SNOW in the open North Atlantic supports previous observations that the atmo sphere must be the predominant mode of transport (J). The wide range of concentrations observed (< I to J50 ppt), in some cases at points only 80 km upon (stations 29 and 33), may be due to scaslicks (2), localized rainfall, or discharges from ships. No relation ship between PC'li concentration and proximity to land was observed. The presence of measurable PCU concen trations, even to depths of 3000 m, suggests (hat animals which migrate vertically, plus sinking shells, fcccS, and dead organisms, transport PCD's out of the mixed layer (about 150 m) and prevent even higher concentrations from accumulating in the productive /one. The Sargasso Sen is an area of high evaporation and tow rainfall. We sug gest that PC8`s, adsorbed on particu lates falling into this region, are par tially solubilized by equilibrating with the surface water. Evaporative codistil lation then transports some of this material to areas of higher precipitation. The volume of the upper 200 m of the North Atlantic is 10,!* liters, if we as sume an average FCB concentration of 2 x 10"8 g/liter in that volume (8), then there may he about 2 x I0IU g (2 X 10* metric tons) of PCB's in the water (/, 9). The total amount of PCB's produced in the United States in 1971 was 1.8 x 10* metric tons (7). On the basis of quantitative estimates of rates of production and rates of loss to the environment, a SDDT/ PCn ratio [ODT refers to DDT, 1,1,1,lrich!oro-2,2-bis(p-chlorophenyl) eth anes, nnd its major metabolites] of 10 is expected in the North Atlantic, if Table I. Concentration* of PCITs in North Atlantic ocean water. The limit of detection was I X 10 * g/liter for a 19-liter sample. Sta- Position lion North Wevt Date 0972) Depth (ns) PCB con centration" (X 10* ii/liicr) 1 S2; 55' 33* 08' 2 44' 00' 30* 36' 1 40' 33' 29* 16' 4 36' 11' 25* 33' 5 34' 02' 22* 50' 6 35' 00* 18* 59' 7 34 47' 14* 57' 8 38* 20' 11* 23' 9 38' 21' 11* 11' 10 38' 19* 19* 28' 11 r 09' 20* 46' u 43' $7' 22* 13' 1) 43' 20' 21* 57' 14 43* 16' 21* 34' IS 46 31' 21* 43' 16 52* 31' 19* 52' 17 52' IS' 19* 53' ID 53' 41' 15' 02' JV 57* 22' 12* or 20 60* 04* 06' 02' 21 60* 09' 05* 36' 22 60* 29' 04* 43' 21 63* 03* 02* 22' 24 41* 32' 70* 40* 25 19' 40' 70* 03' 26 37* 12' 61* 54' 27 34* 32' 67* or 2d 35* 22' 67* 36' 29 35* 17' 61* 28' 30 35* 56' 66* 34' M 36* 05' 67* 27' 32 36* 24' 68* 24' 3) 15* 37' 67* 49' .14 34* 26' 66* 22' 35 3J 41' 65* 44' 36 28* 42' 58* 39' 37 26* 50' 55* 38' 38 25* 56' 34* 15' 39 26* 58' 53* 57' 40 21' 26' 53* 55' 41 31* 13' 53* 45P 6/30 7/3 7/5 7/7 7/9 7/11 7/J3 7/15 7/22 7/23 7/24 7/25 7/27 7/29. 7/30 8/1 8/2 8/4 8/5 8/6 8/7 8/7 8/8 10/2 9/21 9/22 9/23 9/24 9/24 9/25 9/26 9/27 9/27 9/28 9/28 10/3 10/5 10/6 10/7 10/8 10/9 0 0; 200 0; 200 0; 200 0; 200 0; 200 0; 200 0; 200 0; 200 0 0 0 0 100; 3000 0 0; 100 1500 0 200 200 0 0 0; 200 0 0 0 0 1000 0 0 0 0 0 0 0 0 0 0 0 0 0 150 35; 10 4; 7 11; 3 30; 6 14; 5 67; 39 19; 2 41; 13 77 <1 52 47 45; > It 10 45; 8 > It 3 97 42 82 23 21; 7 30 29 36 12 l 2 5 11 22 9 12 IS 26 36 27 42 88 68 The closest tnauhing commercial mlature n all ca* w. that containing S* percent chlorine. Thu* the commercially available Atoclor 1234 (Monsanio) waa sued as the standard. Procedural blanks ranged from 0 to ) na/tliar und war* subtracted from the tabulated concentrations; DDT and it* metabolites, if present, were present at concentrations less than 1 ns/litar. t Poor mulch (nr Atoclor. C44 MUNS (^167 we assume that the half-fives arc simi far (9). I he observed ratio from ou data (and from (2)] must be less that 0.05 (that is, < l ppt/20 ppt (see firs footnote, Tabic 1)]. Thu* the environ mental half-life of the PCB's appear considerably greater thn that of DDt and its metabolites. G tOHCiF. R. ll.SRVI;* William G. Stv.tNttAUtih John M. Thai. Wvotlx Hole Oceanographic InstiHuinn, Woods Hole. Massachusetts 0254.7 n*(ejrncs and Note* 1. Tlie total US. production o( PC9'* umr IV57 I* about 16 K JO` K \Chem. Fnf. Srw, t6 Dec. tV?l), p, HI which is estimated be about one half o( the iota) world cro 2. C. L`. Olnoy .md J fJ. Quinn, paper pi, tmc-.l .i* (Oil of the deliberation* of u,r Internationat Decade ot Decun Hapiiir.idon Baseline t'anfetence, E. O GoWtsrm. dune, man, Hrookhsven National Laboratory, Ui-ton NY., 24-26 May 1972 (these worker* t.te.i. sum! the PCM concentration* In the nirf.io microlaxr and 2u cm below the Mtrfave m the North Atlantic; their subsutfa^ ^<u centratiuns agree with our surface measuretTWnis, although Uieir sample tin was mucismaller). J. G. R. Harvey, V. T. Dowen, R. H. Backus, G. D. Grice, In Nol/rt S>mp<uru*i 20: The Chaliving Chemistry of the Demur, D. Hymen and D. Jagner, Eds. (Almqvtst k Wlksell. Stockholm, IV72), p. 177; dclibtrtattons ot tli, International Decade of Ocean Exploration Baseline Conference, E. D. Goldberg, tbair man. Srookhavett National Laboratory, L'piun. s.Y., 24-26 May 197:. 4. Stations 1 to 23 were occupied on cruise 1C ot R.V. Chain.- station* 2J to 4| were os*upud on cruise 71 o( R.V. Attentfs-H. Station 24 i, the Woods Hole dock. J. Surface samples were collected In a stalnlr-Keel bucket from the bow of the ship white it was under way. Heap samples were coUccteu ;n a 160-liter Bodman bottle lined with Kel-k. R. It. Dodman, V. T. Bowen, L. W. Stabmigh. f. Mar. Rer. 19, HI (1941). 6. Ta parametets (or the use of this min ;j\en in the teat were developed by ttu authors in this laboratory. The effirifiity oi the adsorptive extraction, when compered with solvent extraciioo. is >95 percent. 7. A Packard cas-liqutd chromatograph, msrdc) 407, equipped wlih a N1 iKtrod-cap'ure Oeteciur was used. No motion irnslnvity we, observed in ttio instrument's response. A shipboard analysis revested that Use ship's Paints, greases, end oils did not contain snr PCS'*. 5. These data and (2). In contrast, TC9 eoacc.itratlorti in coastal northeastern Pacific "iters average t ppi (I. Barrett, paper pre tented as part of the deliberations of the International Decade of Ocean Oaplorstion Baseline Conference, E. D. Goldberg, chair man, Brookhaven National Laboratory Upton. N.Y., 24-26 May 1972). 9. This quantity It rcmnrkably similar to a recently calculated estimate of 1.3 x It)4 metric ton* of PCB'S id tha North Atlantic; nu water data were available el the lime of the calculation |1. C. T. Nisbet and A. F Serofkra, Environ. Health Persperr. 1, 2> (I973)J. IP. We thank Dr. R. H. Backus, chief scienilrt on enuse 103 of R.V. Chain, for allowing us ihc opportunity to collect those sample* jnd Dr. V. T. Bowen for making the deep samples available. Supported by print OX 33112 from the Office of the fmeraadunei Decade of Ocean Exploration. Nitlonu Sci ence Foundation nnd grant G Q t.'-Oin (t-* the finvironmenlai Protection Agency w,v-*tHole Oceanographic Institution cnniriOritiun No. 279g. 10 November 1972 SCIENCE, vot