Document vBR10aQEzgMjjgRnqgNJyaVMR

The Toxily of Polychlorinated Biphenyls (PCB) in Sea Water to Gratnmurus Oceanians by D. J. Wii.nisu Fisheries Research Board of Canada Biological Station St. Andrews, N. B. This work was undertaken to investigate some lethal and sublethal effects of PCB following direct uptake from sea water. The dosing system devised by Zitko (1) has been employed. One of the commercially available PCB preparations, Aroclor 1 254 , was tested on Gammarua oaeaniaua. Methods and Materials ' Stock solutions of Aroclor 1254 and Corexit 7664 in various weight ratios were made up in dis tilled water. Test solutions were then prepared by pipetting known volumes of the stock into glass beak ers and making up to 2 litres with sea water. Con trol beakers contained Corexit 7664 in sea water and sea water alone. Five Gammarua were added to each beaker which was maintained at 5 + 0.5 C and the survival time (+ 6 hours) of each animal recorded. Bioassays were continued for 30 days and solutions changed weekly. Resuits and Discussion Apart from some deaths caused by cannibal ism, no mortality occurred In sea water alone or Corexit 7664 in sea water in concentrations up to 1.9 g/1. Colloidal solutions of Aroclor 1254 solu bilized in Corexit 7664 (1:19 W/W) or emulsions (1:10, 1:1, and 1:0.1 W/W) in sea water were lethal at concentrations as low as 0.01 mg/1 and 0.1 mg/i respectively. Observations suggested that moulting or freshly moulted animals were particularly vulner able. Plotting the survival time of G. oceanicua against concentration (Fig. 1) showed a "critical point" of response below which there was, and above which there was no time/concentration effect. The lethal threshold is between 0.001 and 0.01 mg/1 for colloidal solution and between 0.01 and 0.1 mg/1 for emulsions of Aroclor 1254 solubilized in Corexit 7664 in sea water. After exposure to Aroclor 1254 in sea water for periods greater than 150 hours some Gammarua which died were found to have severely ne crosed branchiae. Necrosis was Indicated by a 202 Bullet in of Environments! Contamination & Toxicology, Voi. 5, No. 3, 1970, publiahed by Springer-Ver/tg New York Inc. r*vnmm UHI u t i. . H 'IP 'll r DSW 027902 y 600 400 ZOO E0 i3 600 in 40C 20C C Figure r*". mi ii,i i.ny,i. STLCOPCB4011864 cnyls oanicus gate owing tem of the :1or | Corexit i d1 sired by i$s bea k , Con iter and faker viva! i oassays iged innlba1 ! or ip to I soluins 1etha1 I tng/i iu1ting vulnerticua tica 1 I above . The l/t for tg/l for ixl t * 1254 irs some :ly ne- Concentration, mg/I Figure 1. Median and range of survival time of G. oaeaniaue in Aroclor 1254:Corexit 7664 in sea water. 203 D5W 02 7903 STLCOPCB4011865 chitinous wound callus which isolated the affected brownish tissue. A less extensive, sublethal ne crosis was found in some animals down to 0.001 mg/i of colloidal PCB in sea water. A sublethal branchial oedema was attributed to the effect of Corexit 7664 in sea water effective at a concentration down to 0.19 mg/1. Other data (2) show that the highest con centration of Corexit 7664 used (1.9 g/l) to solu bilize Aroclor 1254 is 15 times lower than the 48-hr LC50, and thus no mortality was caused directly by the emulsifier. Nevertheless it is possible that.a synergistic effect occurred between the emulsifier and PCB. References 1. ZITKO, V. Bull Environ. Contamination and Toxicol. 2. WILDISH, D. J. Fisheries Research Board of Canada, MS Report No. 1084. Polychlorinated biphenyls in sea water: bioassay of Gammaruo oaeaniauB (May 1970). i i This out at Mar tensive ef quality uj Fish Avoic Many centrarech areas when important the fish c fish type reaction a pearance c tant to th this time dealing wi fish life informatio would be p The f general fi fish, shin abundance bass and w population tion cause ditions mo diverse sa: thirty yea. carp and g' migratory Hudson lis species cor In ore glass tank to that des are fine pi connected t 204 Bulletin of Eiavironir VoL 5, No. 3, 1970, p -- "w "w-i "m ,m' !' l.i .I'f ipi ninn|.,t1 iiw,u.uuii mi .L. n.i,iWilf OSM 027904 J' STLCOPCB4011866