Document 4JMnZQGZ4Rm1D1g0xQv5bXdm1

Morins Biology It. tOl--tB7 (1071) O hr Spitas*r*Vrls( 1*71 ' Toxicity and dislrUmlion of Aroclor 1254 in the pink shrimp Penaeus duorarum* , D. R. Nimmo, R. R. Blaokma*, A. J. Wilsoic, Jr. Mid J. Foiutnw Environmental Protootion Agoney, Gulf Breoie Loboratoryi Sabins Island, Gulf Onus, Florida, USA AUtraet Tlie polychlorinated biplionyl Aroclor 1254 wu re leased in an accidental leakage of hoat-oxchango fluid from an Industrial plant, into tho Kscambia Hivor, near Ponaaool*. Florida, USA. This material warn carried downstream, and is nofr found in tho fauna of Etoarabia Bay and Its contiguous waters, prime nursery areas for Qshos and invertebrates such as penaeid shrimp. Tho significance of pollution by this chem ical was assessed by ott&blisbing toxiuty tevola, determining routes of entry, and Investigating its morsment and distribu tion in Tsrious tissue* of shrimp under controlled conditions in the laboratory. Aroclor 1254 added to the water wss toxio to tha juvanils pink shrimp Pno*v* ivorvrum at a oonesatration of 1.0 part par billion within 15 day*, but wss lass Registered trademark, Monsanto Company, St. Louis, Missouri. Mention of oommeroisl products does not constitute endorsement by the Environmental Protection Agency. * Contribution No. 128, Gulf Brea* Laboratory. toxic to adult pink shrimp. Shrimp obtained tho contaminant from water and food and oonoontratod it to 510.0 parts por million in the hopatopancroaa. Aroclor 1254 residue data from shrimp oollected in the estuary are inoluded in the study. Introduction Sinoo I960, pesticide toxicologists and ecologists have become increasingly aware of polychlorinated biphenyls (PCBs). First discovered in fishes, feathers, and human hair (Jxkssn, 1966), residues have since been found in many organisms from diverse areas of the world. Structurally, PCBs resemble ohlorinated hydrocarbon pesticides such os DDT, and are widely used in formulating plastioa, resins for rubber-based lacquers, varnishes, paints, lubricants, heat-transfer fluids and electrical insulators. PCBs are relatively l Martas stilisr. Tot, n DSW 032828 STLCOPCB4016790 1W D. R. Nikmo t ].! Aroelor In Ptnaoui Ji itor. Biol. out' Fig. t. Residues of Aroolor 1254 (in ppm) fimad in sediment* from Bsosmbia B*y uwi eontiauous wotm* during 1969/1970. N.D.: less than 0.03 ppm insoluble in water, but solublo in lipid nnd lipid sol- and distribution of this PCB in the organa of the pink vcnti. In addition to their thormsl stability they are shrimp Ptiuuus dwrarum. also resistant to acid and base, and therefore, persist in the environment. PCBs ore toxio to trout and blue gill (spp. not Materials and methods givon) -- QutTAFtOM, 1070; shrimp (Pmatut duora- Shrimp for laboratory studies were obtained from rum) and oystors (Crastotlrta virginica) -- Dru et al., two sources. Juvenile (2.5 to 3.8 cm) pink shrimp 1070; and a huh (Layodon rhomboid**) -- IIaxskx {Ptnatu* duoraiunt) were collected with a small net et al., 1071. Also, a 1*CB used as a binder in epoxy paint from Sant* Rosa Sound at Pensacola Beach, Florida, was toxic to chickens (Gustatson, 1070). Abnormally in June through September. Adult pink shrimp from thin-shollcd eggs of birds in Great Britain and North Tampa, Florida, wero purchased from a live-bait Amorica woro associated with roakluoe of chlorinated dealer. Background concentrations of chlorinated hy- hydrocarbons including tho PCBs (Risebbouoji et al., drooarbon compounds in tho hcpatopancrcoscs oi all 11)08). In 1900, a 1*011 (Aroolor 1254) waa disooverod shrimp never exooeded 0.6 parts per million (ppm); as a contaminant in water, sodimont and fauna of whole-body residues were less than 0.01 ppm. Escambia Bay, Florida (Duke ot al., 1070). One source All shrimp were acclimated in flowing sea water of this material was traced to an aocidontel leak in a for eovoral days in tho laboratory. Juveniles fed on hcat-oxcliango system of an industrial plant located detritus carried in by tho (lowing unfiltcrcd sea w ater several kilometers upstream in Escambia Kivor. It is and adults were fod mullet (AIvyil cephalit.i) muscle now present in estuarine organisms, including shrimp containing loos titan 0.03 ppnt organochlorinc com captured from Escambia Bay and contiguous waters pounds each day. Beach sand with no dctcctnblc (Fig. 1). Sediments from the rivor and uppor bay appear ' organochlorino compounds was provided os a sub to bo a reservoir for tho oompound (Fig. 2). In oarlior strate for tho ihrimp. cxporimonW, shrimp oxposed to thoso sodimont* for Shrimp wero expoood to Aroelor 1254 (hereafter 80 days accumulated tiro chomioal (Nimho ot al., oaltod Aroolor) in flowing-water systems. The Aroelor 1071). In this paper wo report toxicity of Aroolor 1254 was dissolved in polyethylene glycol 200, infused into in water, rates of accumulation from food and water. tho flowing water with syringe pumps, then mixed by DSW 032829 STLCOPCB4016791 rtt/f, Me. 3. mu 0. R. NlMun <'V *1.: Aroolor in I'twru* <lnornrum ion a scries of balTics a* it (lowed into aquaria. The volume of the aquaria varied from IS to 100 1 commensurate until the number* and sizes of tent animals and flow rate of water. Animal to volmno ratio was 1 animal per 2 1 water. Concentrations of Aroelor wore routinoly measured by gas chromatography. No attempt was roado to control salinities whioh ranged from 25 to 32%,, but o$octrio aquarium boaters wore used U> main tain water temperatures between 20* and 30 *C. Fig. 3. Aroolor chromatograms. (A) Arosior ISM standard, (B) Aroolor 1254, reoovorad from Ptnatut duorarvm bepstopsnersa* after shrimp* had baea fod fish containing material (soe Tabla 4). Concentrations of DDT and its metabolites war* nogligiblo, therefore, no sttempt was mads to separate them from Aroolor isomers. Go* flow 25 ml/min, nitrogen; Injsotion tempsrsturs 210 *C, oven temperature 19o*C, detector tempsrsturs 210 *C; H* electron ospture deteotor; 152.4 v 0.317 cm glsee-oolumn psoked with 2% OV-1 on 100/120 Oee Cbrorn Q Concentrations of Aroelor in shrimp wero deter mined from pooled samples by gss ohromatograpby. When a group of 10 shrimp was exposed to a constant concentration of Aroolor in flowing-water, individual residues differed by a factor of 10. Consequently, laboratory analyses are from composite samples of at least 10 individuals, unless stated otherwise. All analyses on Peruuus duorarum from Escambia Bay and contiguous waters were on composite samples of at 5 individuals. * Depending on type and weight of the .samples, four method* of pro|invtion wero employed, (t) Samples of shrimp or food items larger than 1 g were mixed with anhydrous sodium sulfate in a blender and oxtrncted for 4 h with pctroloum ether in a Soxhlct apparatus. Extracts wero concentrated and eluted from a FJoriail column with 0%'ethyl ether in pctro loum ether. (2) Sample* low than 1 g wero analyzed by a modification of tho micro-method of Enos (private oommunioation). Samples wero woighed in Duall1 tissue grindors and oxtraotod with throe 2.0 mi portions of aootonitrilo. The aootonitrilc extracts were combined and diluted with 6 ml of 2% X'a, SO, in distiilod water, then agitated and oxtractcd with three 2.0 ml portions of hoxano. Thoso oxtracts were com bined and concentrated to about 0.5 ml, then trans ferred to a Size "B" Chromaflcx1 column containing 1.5 g of Florisil topped with 1.5 g of anhydrous sodium sulfate. The residue was eluted from tho column with 20.0 ml of 1 % ethyl ether in hoxanc. (3) Water samples were extracted with petroleum ether, thon the extracts wero dried with anhydrous sodium sulfate and re duced to an appropriate volume. (4) Sediments were analyzed by tho method of Kiumo ct al. (1971). All cluates wore adjusted to an appropriate volume for analysis by cloctron-oapturo gas chromatographs equipped with OV-1 columns. Quantitation of Aroelor 1254, a multiple-peaked compound, was mado by averaging tho heights of 5 major peaks which had retention times relative to aldrin of 1.31 [IV), 1.55 (F), 2.32 (VIII), 2.74 (IX) and 3.27 (A') (Fig. 3). Interference from DDT was nogligiblo duo to tho relatively high residues ofAroelor 1254 in most samples. Laboratory tests indicated rooovery rates abovo 80%, but data in this report do not includo a correction fac tor for recovery. The presence of Aroelor 1254 in shrimp and sediments was verified by mass speotrosoopy at the Environmental Protection Agency La boratory, Athena, Georgia. Results Acute and chronic biosassays Aoute toxicity tests at this laboratory showed that Aroolor was about one tenth as toxic to juvenile Penaeus duorarum as DDT (Table 1). For example, 10.0 parts per billion (ppb) DDT in the water lulled 100% of a population of shrimp in 96 h. whereas 100.0 ppb in tho water was necessary to obtain tho same results with Aroolor. In ohronie flowing-water bioassays, Aroelor at 0.04 ppb killed 51% of the juvenilo shrimp (2.5 to 3.8 cm) within 15 days (Table 2). Juvenile shrimp were more sensitive to Aroolor than adults. Exposure to 3.5 ppb for 35 days resulted in a mortality of 60 % in a group of adult ahrimp (0,5 to 12.5 om). Tbo data 1 Kontos Glass Co., Vineland, N. J., USA. DSW 032830 STLCOPCB4016792 104 D. R. NlXMO t al.; Aroolor in Pimiw iucrantm ' Afar. Hid show the need for challenging eoyeral stegoa In the life cyolo of shrimp with chomJoek such aa Aroolor. Wo have obaonrod that symptoms of Aroolor poisoning in ahrimp art different from thoae of moot organochlorino inaootioidoa. Pink ahrimp which we expoaod to 0.15 ppb or more DDT ahowod norrona impairmcnU such aa tremor*, loaa of equilibrium and, finally, ;>araly*i* as doflnod by coaaation of Iooomotor movements. In testa with Aroolor, regardleaa of ita oonoontration, ahrimp ahowod delayed mortality and died at a rate of one or two per day with no apparent prior aymptoma of poiaoning. Like othore (Dora, at al., 1970; Wildish, 1070), we auggaat that oruataoeana may bo more auaooptiblo to the chemical during molting. Accumulation and transfer of Aroclor in (issues The uptake of Aroclor from water by adult Penasus duorarutn (3.8 to 7.0 om) and the tronslocatlon to the hopatopanoroas, whole body and ab. dominal muscle was measured (Fig. 4). Accumulation was linear with timo in the hepatopancroas (r -- 0.97) and wholo body (rTM 0.90), but a plateau was reached Table 1. Ptnaaos ivorarum. Comparison of tooioitUs of p,p' -- DDT arJ. .-trader 1ZS4 to shrimp in ftowi<w-\oottr tests. ifto* temperature and salinity of too teator in DDT trperimsnt wor* ZJ *C and ZS U rupoetiotlp; for Aroolor 1ZS4,19 *0 and 31X. DDT* Test concentration (ppb) Morulit? 48 h 90 h (%) \Xi Aroclor 1204* teat concentration (ppb) Mortality 48 h 90 h (%) (%) 10.0 1.0 0.5 0.1 Oontrol 100 too 30 80 0 40 10 80 00 100.0 10.0 1.0 Oontrol 80 100 00 00 00 Personal communication, J. I. Lows, Snrironmantal Protection Agenoy, Quit Bren, Florida UMt, DBA. * Doxs *t aL, 1970. Jig. 4. Ptnotui duomrum. Rates of absorption of Aroclor 1254, in various tissues of shrimp exposed to 2.5 ppb of tho chemical in flowing water. Unexpoeed shrimp showed no detectable residue, r - correlation coefficient Table 2. JteswA* of ohronio tianseays with Aroclor ItSi and Ik* pink shrimp Psnaous dnorantm in flowing water Shrimp rostrum* tolaon length (ora) Concentration* Average (Ppb) salinity (X.) Average No. oftMt sr"* individuals I 1 Days exposed Average mortality (%) Level of eignificanoe *.5 - 3.8 8.5 - 8.8 2.5 - 3.8 2.5 - 3.8 2.5 - 3J 4.2 - 7.2 4.8- 7.8 4.2 - IJt 0.0 - 9.0 0.0 - 9.0 7.0 - 83 7.0-83 9.5- 183 03-115 Control 037 0.94 9.4 10.0 Control 8.4 3.1 Oontrol 4.3 Control 4.0 Control 33 32 38 32 23 - 38 29 80 38 30 38 31 31 38 88 39 89 29 38 30 28 28 28 80 SO 20 89 20 80 * Average of at least three determinations, * Student's (.test. * Chi-aquara. 45 5 IS 12 80 2 15 30 0.10* 45 3 15 51 0.005" 20 2 15 00 0.001* 20 2 15 100 0.001* 23 1 32 4 -- 20 1 17 05 0.001* 25 1 32 60 0.001* 43 1 53 20 -- 40 1 53 83 0.001* 00 1 18 8 _ 00 1 18 41 0.001* so 1 35 8 -- BO 1 35 50 0.001* DSW 032831 STLCOPCB4016793 Vet. 11, No. 3, 1071 D. It. NutMO fit *1.: Aroolor in Penotiu duororum too v*"\ *00 3 w too in CM o: aoo 2 oo cc 100 ** <t- too O IQS ELIMINATION TIME (weeks) Fig. 5. Ptnatu* duororum. Rates of elimination from hepstopsnorea* and subsequent inoreaee in remaining titauo. Shrimp were expotod to 7.5 ppb Aroolor 1254 in flowing water for 1C days, then placed in Aroolor-free environment. Compotite tiwue templet from * individual* were analysed for each determination. Unexposed ehrimp ihowed no detectable reeiduet. - r - correlation coefficient in the muscle within 2 days, with little inoreaee there after. Residues in the hepatopanoreae reached 510.0 ppm after 22 days and represented a 2.04 x 10* in crease over the 2.5 ppb Aroolor in the test water. During this experiment, 50% of the exposed and 7% of ths unexposed shrimp died. In a subsequent experiment, most of the Aroolor was lost from the hepstopanoress and transferred to other tissues (Fig. 5). Adult shrimp (0.5 to 11.5 om) were first exposed to 7.5 ppb Aroolor in the water for 10 days, then placed in an Arocior-free environment for 5 weeks. Total weight (|ig) in the hepatopanoreae decreased by 80% in 5 weeks, but that in the remain ing tissues almost doubled. Whole-body loss was from 731 to 456 fig or about 00% in 5 week*. A slightly different pieture exists eonoeraing the loss of Aroolor from the tissues if wo express the amount in parta por million (Fig. 5). Aroolor (in ppm) ihowod little change in tissues other than the hopatopancroaa during post exposure. In contrast, tho rato of elimination from tho hop*topancroon was eonstant and linear with time (r 0.00), the biologioal halflife in this organ being 17 days. Aroolor is more persistent in the othor tissues of shrimp than DDT, ths in secticide being oompletoly eliminated In 8 weeks (Xxmxo st al., 1070). While tho Penatus duororum wero held in tho Aroelor-froe environment, 23% of the expoeod ehrimp diod, with no loss of the unexpoeed. Accumulation in body organs Reeiduee found in laboratory experiments are com pared with thoee in natural populations of shrimps in Esoambia and Pentaoola Bays in Table 3. In all tests, the shrimp incorporated the chemical. The propor tion of Aroolor in tissues of shrimp which were exposed to 0.2 ppb in the water for 50 days was nearest to that found in shrimps osptured alive from the bays. The distribution of Aroolor in the tissues of shrimp is muoh the same as DDT, maximum amounts oc curring in the hepatopancreas and least in abdominal musole or exoskeleton (Nimmo et al., 1970). Generally, the distribution of Aroolor in the tissues of Pinatus duororum corresponded to the amount of lipid in the tissues. We believe water and food are sources of Aroclor to shrimp, but we do not know which contributes more. Farfantb (1000) summarized earlier work on the foeding habits of shrimp and reported that the throe eommoroially-iraportant ponaoid shrimps, pink Penaeus duororum, white P. setiferui, and brown P. axioms, are omnivorous. Somo of the contents found in digestive tracts by othor investigators includo inorganio debris, detritus, and a variety of algao, in cluding diatoms. Aroolor attached to detrital material in aquaria or in field substrates was probably ingested by ths shrimp. QSW 032832 STLCOPCB4016794 100 D. R. NnnfO et *1.: Aroolor In Psnasus duorarum , Har. uiol. Tablo 3. Distribution of Aroclor 1254 in tissuss of exposed Ptnaeue duorarum which had accumulated chtmieal from water and food and in penatid ehritnpe from natural populations in the Pensacola estuary, i'iorida, USA Method* of oxpotura Hopato- Ventral Digestive Itoart Gill* Exo- Abjomma', panoreos norve traot skeloton musclo PPm _________ _ Weler ]'m!< *hrimp oxpoted to 3,5 ppb Aroolor In vmtor for `,15 <lny Pink shrimp exposed to 0.2 ppb Aroolor 1b water for 50 days Food Pink ihnmp fed spot* (43.0 ppm whole body) for 16 day* Pink shrimp fed spot (flold-oaptured, 0.2 ppm whole body) for 10 day* Pink shrimp fod croskor* (0.68 ppm la musole) for 30 days Natural populations Pink shrimp captured 10. I. 1070* Pink shrimp captured 3. IV. 1070* Whito shrimp captured 28. VIII. 1970* Brown shrimp captured 28. VIII. 1970* 108 30 146 0.6 5A 16 4.6 17 08 120 3.3 32 3.2 8 16 0.6 <0.1 2.0 1.0 9.4 1.1 0.6 0.6 4.0 1A 14 0.7 77 60 U 2.8 1.4 0.8 26 38 6.3 0.3 0.3 0.2 IJ 0.9 o.e -- 0.3 1.0 4.2 1.4 0.6 0.3 0.2 0.8 0.8 3.1 2.2 The spot Dtiotlomus xanlhurus were previously exposed to 0.0 ppb Aroolor 1204 in the water for 12 day*. * Atlantic croaker hlieropogon undulatus were oeptured in Esoarabis Bey, Florida. Pensacola Bay. * Escambia Bay. 15 0.7 67 <0.1 0.6 0.9 0.1 1.3 0.0 Table 4. Percentages' of 5 peaks in Aroolor 1254 recovered molecule* or differential solubilities in the various from water, fish and Ptnasus duorarum systems. Item Poak (%) IV V VIII ix X Standard 10.0 18.5 26.0 22.2 20.0 Water (30 X, S) 8.2 15.0 30.0 22.8 23.1 Fish muscle* 6.1 10.8 27.4 27.9 28.4 Shrimp hepstopancress* 2A 10.0 23.0 31.1 31.1 peak height ^ l00 turn of 5 pooka * Tho Atlantic aroskorilieropoqon undulatus were captured from Escambia Bay and oontoined 0.68 ppm Aroolor 1254. Tho shrimp ?imw duorarum were fod Atlantio oraaker muaolo. Wo investigated' di/foronoes in tho proportion of Aroclor peaks with respect o tiio standard; the chango is greatest in tho hopatopancreas of shrimp (Fig. 3; Table 4). lleiglitH of 0 peaks used for quantitation of the chcinicu.1 show tho greatest reduction in peaks IV and V, with sorno increase in IX and X. We do not know whether this reflects actual alterations in tho Results of field studies Distribution of shrimp in the estuary in relation to salinity is a faotor which regulates the Amount of Aroolor in the body (Fig. 1). The brown shrimp Penaeus cutecus from upper Escambia Bay had the highest residues (132.0 ppm in the hepatopancreas). The white shrimp P. setiferus from the mouths of small streams emptying into Escambia Bay had a maximum residue of 50.0 ppm. The highest residue in the pink shrimp P. duorarum captured in Pensacola Bay was 15,0 ppm. P. sttijerus is most abundant in low salinity waters of less than 10%, and P. azteevs occurs mostly in waters of 10%, or more; the abun dance of P. duorarum is not as dependent on salinity (FsnrANTS, 19G9). Although this distribution may vary with localo, types of substrate and seasonal temperaturcs, shrimp with the highest residue* in this study were thoso captured in the lower salinities. Because higher concentrations of Aroclor occur in the sediments of up|>cr Escambia Bay (Fig. 2), it is possible that ` burrowing activities of brown shrimp in these sedi ments could liavo caused additional absorption of lonohod ohomieal through tho gills (Xi.m.mo ct ah. 1071) as well as ingestion of contaminated food. DSW 032833 STLCOPCB4016795 Pol. JJ. .Vo. J. 10T1 D. K. NlMMO ot al.: Aroclor in Peiuietu Juorarum 107 Discussion and conclusion* In our investigations, Micro has liocn no oviilcnco Mint Aroclor in Mio wider, KcdinicnU, or biota in Escambia Day wax toxic to Hhi'iinp. Wo found no dead or dying shrimp in arena of "fish kills" which occurred frequently during summer month* of Uio past- t wo years. Aroclor in walci samples collected 48 cm above t-ho aedimenta in the upper Day wna lielmv (.bat considered toxic to shrimp, but it wu dolcctoblo (0.08 ppb in unfillured water). It probably leached from tho sediment* or was attached to suspended particulate matter. Adult shrimp in livo cages placod directly on sediments in upper Escambia Bay for 3 weeks did not dio nor did tho "oontrola" held 48 om above in an unoontaminatod substratum. Shrimp on lower sediments accumulated almost 3 times more Aroclor (6.7 ppm in the hopstopancreos) than did controls. Nevertheless, our laboratory investigations show that Aroclor 1254 in solution is toxic in the 1 ppb rango to shrimp. Therefore, tho occurrence of this ohcmical in tho water of Escambia Hay or in othor estuarine areas is reason for concern. We also believe the residues found in shrimp from the Escambia Bay are high enough to be of importance, although we have not found a correlation between residues and mortality. If postlarval or juvenile shrimp were exposed direotly to tho sediments in upper Escambia Bay for a period of weeks, a threat could exist because of availability of PCB-laden detritus and also the leaching of the chemical at the water-substrate interface. We are now investigating this possibility. Deaths of shrimp due to this or any othor con taminant in natural environment! would be difBonlt to observe. Except as larvae, shrimp ore primarily benthio, secretive animals, and hide by burrowing in the sediment. If they are active at night, they usually remain bolow the substrate by day. Here, thoy may obtain higher concentrations of Aroolor than when swimming, and if they dio, dead shrimp do not surface after dying an do fish, rather thoy dooomposo rapidly or arc quickly eaten by predators. Aroclor occurs in tho tissues of shrimp wliioh were captured soveral kilometers from the original Bouroos of the material in Escambia Bay (Fig. 1). This suggests the potential of this material to be dispersed through the ecosystem, and it might be available to man through his seafood. We believe this contamination should serve as a warning to increase monitoring of the environment for Aroolor and related industrial mat*, rials. Summary . V A concentration of 1.0 part per billion of Aroolor in the water kills the juvenile pink shrimp PmuuMt duorarvm within 15 days in tho laboratory. Adult shrimp are not ob suHCoplihle, but higher concentra tions of 2.4 to 4.3 ppb kill within 17 to 5:1 days __ defending on tho maturity of test individuals. 2. In inliorntoiy tests in which Aroclor was added to tho water, P. duorumm alworbod the material and concentrated it in the heputopancroas. Subsequently, it was transferred to other tissues, then lost. It was moro persistent in the tissues of shrimp than the ohomioally-rolatod pesticide, DDT. 3. Aroclor woe absorbed from tho water and its subsequent distribution in tissuos was similar to that found, in wild shrimp from contaminated areas. In the laboratory, shrimp also obtained the Aroclor from food, and wo conclude that both sources are available to shrimp in the Ponsaoola estuary. 4. Concentrations of Aroclor in P. duorarum from the estuary appear to rofloot distribution patterns in shrimp. Aroclor in shrimp captured at considerable distances (up to 24 km) from tho original sourco demonstrate the potential for dispersion and concen tration of this material in an ooosystem. Literature cited Dots, T. W., J. I. Lows and A. J. Wilson, Jr.: A poly, chlorinated biphenyl (Aroolor 1254) in the water, sediment, and biota of Escambia Bay, Florida. Bull. Envir. Contam. Toxiool. 6, 171--180 (1070). Faefanti, I. P.: Western Atlontio shrimps of the genus Ptnatui. Fishery Bull. Fish Wildl. Serr. Ui>. 07, 461--491 (1069). GUSTAFSON, C. G.: PCB's.prevalont and persistent. Envir. Soi. Teohnol. 4. 814--810 (1070). Hansen, D. J., P. R. Passish, J. I. Lows, A. J. Wilson, Jr. and P. D. Wilson: Chronio toxioity, uptake, and reten tion of Aroolor9 1254 in two estuarine fishes. Bull. Envir. Contain. Toxiool. 0, 113--110 (1971). Jensen, 8.; Report of a new ohemiosl haoard. New Sci. 32, 612 (1006). Nano, D. R,, A. J. Wilson. Jr. and R. R. Blackman: Localisation of DDT in tho body organs of pink and white shrimp. Bull. Knvir. Contam. Toxiool. 5. 33.1--341 (107(1). --, 1*. D. Wilson, U. R. Blackman anil A. J. Wilson, Jr.: Polyohlorinatod biphenyl absorbed from sediments by fidulor orabs and pink shrimp. Nature, Lond. 231, 50-- 52 (1971). RlSEimouoii, R. W., P. Rieciie, D. B. Pkakall. S. G. Hrn9JAN and M. N. Kikven: Polychlorinated biphenyls in global eootyatam. Nature, fond. 220. 1006--1102 90s). Wildish, D. J.: Tho toxicity of polychlorinated biphonyls (PCB) in soa water to Qammaru* octanieiu. Bull. Envir. Contam. Toxiool. 5, 202--204 (1970). First author's address; Dr. D. R. Nossio Environmental Protection Agency Gulf Breexe Laboratory 8abin Island Gulf Breesa, Florida 32561 USA Data of final manuscript aoosptanoe: Juno 23, 1971. Oommunioatod by J. Bunt, Miami OSW 032834 STLCOPCB4016796