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Organochlorine Contaminants in a Sea Lamprey (Petromyzon Marinus) from Lake Ontario
J. Great Lakes Res., June 1978 Internat. Assoc. Great Lakes Res. 4(2):234-236
NOTE ORGANOCHLORINE CONTAMINANTS IN A SEA LAMPREY (PETROMYZON MARINUS) FROM LAKE ONTARIO
Klaus L. E. Kaiser and Ilze Valdmanis National Water Research Institute Canada Centre for Inland Waters P. O. Box 5050, Burlington, Ontario L 7R 4A6
ABSTRACT. A sea lamprey (Petromyzon marinus) specimen from Hamilton Beach, Lake Ontario, was analyzed for organochlorine pesticide and PCB residues. Contrary to the expectations, the residue levels observed were similar to those found in salmonid species. The concentrations of PCBs, DDT and metabolites, and mirex all exceeded the existing guidelines and proposed water quality objectives. Other organochlorine residues are below such limits, where existing. It is recommended to investigate organochlorine residues in sea lamprey from the Great Lakes in more detail.
INTRODUCTION In the Great Lakes basin, sea lamprey research has primarily dealt with the efficacy of the control measures and the larval state of the lamprey in tributaries. There is little information, however, on the behavior and habitat of the sea lamprey in the adult stage in open lake waters. This lack of information is remarkable in view of some $30 million spent for the lamprey control program since its inauguration. In the same period, largescale environmental surveillance programs of fishes, waters and sediments of the Great Lakes under the auspices of the International Joint Commission (IJC) and other agencies have resulted in a large data base with thousands of observations on contaminants in fish. Thus, it is surprising that not a single report on organochlorine contamination in Great Lakes' sea lamprey can be found in the data base on fish in Ontario waters (OMNR 1977). The report presented here is the result of a detailed investigation of organochlorine residues in a single specimen of sea lamprey from Hamilton Beach, Lake Ontario.
until workup. Solvents were of pesticide grade, glassware was washed with pesticide grade ~olvents and baked at 300°C. After thawing, the lamprey was cut into pieces 2 to 4 cm in length. The pieces were combined and ground with Polytron, Waring, and Virtis blenders which resulted in homogenization of the tissues. However, none of these methods achieved homogenization of the lamprey skin. Therefore, the skin fragments and tissue mixture were ground in a porcelain mortar together with 20 to 30 mesh pre-extracted Ottawa sand (Fisher Scientific Co.) and anhydrous sodium sulfate that had been baked at 550°C. The resulting mixture was divided into four approximately equal portions. Three of these portions were placed in separate Pyrex Soxlet extraction thimbles with sintered glass bases and each was extracted under reflux for 17 hours with an equal volume mixture of hexane and acetone. The three extracts obtained were combined and extracted with one liter distilled water, which had been pre-extracted with hexane. The aqueous phase was separated and re-extracted with 250 mL hexane. The organic phase was extracted with another 750 mL distilled water which was reextracted again with 100 ml benzene after the addition of 500 mL of a saturated aqueous sodium sulfate solution to break the emulsion which had resulted. All aqueous phases were then discarded. The organic phases were combined, dried with
MATERIALS AND METHODS A female sea lamprey (Petromyzon marinus), weighing 350 g, was caught by a diver off Hamilton Beach, Lake Ontario, where it was attached to an instrument at approximately 7.0 m depth, on 12 December, 1976. After removal of kidney and gill samples for other purposes, the lamprey was frozen 234
235
NOTE - ORGANOCHLORINE RESIDUES IN SEA LAMPREY
anhydrous sodium sulfate and concentrated on a rotary evaporator at 40°C to approximately 50 mL. The extract was then transferred to a 100 ml volumetric flask and made up to volume with iso-octane. One mL of the extract (100 mL) was injected onto a high pressure liquid chromatograph with a 1 m x 0.8 cm SS column packed with Porasil A in iso-octane. The column was sequentially eluted at a flow rate of 2 mL/min with 22 mL each of the four solvents: iso-octane, 20 per cent benzene in iso-octane, benzene, iso-octane. The volume of each elutant was reduced to 10 mL in a Vortex evaporator at 40°C and each solution was subjected to gas chromatography on three different stationary phases according to the method of Sampson et al. (1977) described in the methods of organochlorine pesticide analysis in the Analytical Methods Manual, Water Quality Branch, Inland Waters Directorate. With the exception of PCBs, all organochlorine pesticide residues reported were confirmed with the three-column gas chromatographic technique (Sampson et al. 1977). For the calculation of the results, a total weight of 250 g was assumed for the three tissue portions analyzed as the fourth portion was lost and the quantitative extraction of the only partially homogenized lamprey skin was not guaranteed. PCB levels were calculated using the method by Webb and McCall (1973), as modified by Chau and Sampson (1975) for electronic data reduction. RESULTS AND DISCUSSION
The sea lamprey specimen investigated contained eleven organochlorine pesticide contaminants above the quantification limits. The concentrations, calculated on a whole fish wet weight basis, as indicated above, are given in Table 1. In addition, high PCB residues were observed which exceeded the Canadian Food and Drug Directorate guideline of 2 p.g/g in edible portions of fish by a factor of approximately two. Mirex exceeded the U.S. Food and Drug Administration guidelines of 0.1 p.g/g by a similar degree. Mirex, DDT, and PCBs also greatly exceeded the proposed water quality objectives for the Great Lakes (IJC 1976). The residue levels of lindane, dieldrin, and endrin were found to be below the recommended maximum levels for the protection of human consumers of fish. No numerical guidelines are presently set for any of the other organochlorine pesticides observed. The observed residue levels, as shown in Table 1,
TABLE 1. Organochlorine contaminant concentrations in a sea lamprey specimen from Lake Ontario; data on whole fish, wet weight basis. Contaminant
Concentration [p.gJgJ
PCBs p,p'. DDE p,p' - DDD p,p'. DDT
3.62
mirex 'Y-chlordane a-chlordane
HCB dieldrin
a-BHC lindane endrin
1.38
0.25 0.09 0.18 0.17 0.12 0.090 0.082 0.035 0.Ql6
0.008
are quite similar to those of the common teleosts. For example, edible portions of brown trout, chinook salmon, coho salmon, and splake from Lake Ontario have mirex residue means of 0.22, 0.18, 0.17, and 0.16 p.g/g, respectively (Water Quality Board, 1977). For comparison, the mirex concentrations in the investigated whole lamprey specimen was 0.18 p.g/g. Similarly, PCB residues in brown trout, chinook salmon, coho salmon, and lake trout were 5.3, 13.1, 8.4, and 9.4 p.g/g, respectively, in 1975 (Water Quality Board 1976), compared to 3.6 p.g/g in the sea lamprey. Comparable residue levels are also indicated for the other organochlorine contaminants. In contrast to the multitude of data on organochlorine residues in edible portions or whole fish, little is known about their concurrent concentrations in fish blood. Experiments with radioactive PCBs showed quick dispersion of the contaminant within certain fatty tissues without any appreciable concentration of the PCBs in the blood of carp (Yoshida et al. 1973). This observation is supported by the known, extremely low solubility of PCBs in water and as a result, one must question the assumption of the sea lamprey feeding primarily on the blood of the host fishes. Based on the similarity of the residue levels in hosts and lamprey, it appears possible that lamprey take up and digest considerable portions of their hosts' tissues. It may be argued that the analysis of one specimen is of little value is assessing the contaminant burden of that species in the entire lake. There is always a possibility of local contamination in certain nearshore areas, but migratory fish species, which spend a large fraction of their adult life in
KAISER and VALDMANIS
236
the open lake waters, are less likely to be affected by local conditions. Also, it has been found that the observation of an organochlorine contaminant in one specimen can be quite indicative of a lakewide contamination, as was shown for example with the organochlorine contaminant mirex (Kaiser 1974, Water Quality Board 1977). Further, it is known that the ratios of the various contaminant levels are often very similar within one species while the levels may vary with the specimen's size and age (Kelso and Frank 1974, Bache et al. 1972). As a result, the finding of the significant contamination of this sea lamprey specimen by a multitude of organochlorine contaminants, in particular PCBs, mirex, and DDT group residues, should be considered evidence of the contamination of this species in all of Lake Ontario. In consideration of the ecological importance of this species in the Great Lakes, this contamination indicates the need for in-depth studies of the organochlorine residues of sea lamprey in the Great Lakes. Such investigations may lead to a better understanding both of the sea lamprey itself as well as its interaction with preferred salmonid fish stocks. ACKNOWLEDGMENTS The cooperation of Dr. A. Niimi, Dr. P. V. Hodson, and Miss B. Blunt is greatly appreciated. REFERENCES Bache, C. A., Serum, J. W., Youngs, W. D., and List, D. J., 1972. Polychlorinated biphenyl residues: Accumulation in Cayuga lake trout with age. Science, 177: 1191-1192.
Chau, A. S. Y. and Sampson, R. C. J. 1975. Electron cap· ture gas chromatographic methodology for the quantita. tion of polychlorinated biphenyls: survey and compromise. Environ. Lett. 8:89-101. I. J. C. 1976. Proposed new and revised water quality ojbectives. International Joint Commission, Windsor, Ontario, 182 pp. Kaiser, K. L. E. 1974. Mirex: An unrecognized contaminant of fishes from Lake Ontario. Science 185 :523·525. Kelso, J. R. M. and R. Frank. 1974. Organochlorine residues, mercury, copper and cadmium in yellow perch, white bass and smallmouth bass, Long Point Bay, Lake Erie. Trans. Amer. Fish. Soc. 103:577-581. OMNR. 1977. Ontario Ministry of Natural Resources, Fisheries Branch. Contaminants levels in Ontario fish, a data summary. Toronto, Ontario, October 1977. Sampson, R., Valdmanis, I., Larose, R. H., and Wolkoff, A. W. 1977. Unpublished report. Procedure for the quantitative liquid chromatographic separation and cleanup of 18 organochlorine pesticides and PCBs in extracts of water, wastewater, fish or sediment. 1 April, 1977. Water Quality Board. 1976. Great Lakes Water Quality, 1975. Annual Report, Appendix B. Annual Report of the Surveillance Subcommittee. Internatl. Joint Commission, Windsor, Ontario. p. 138. _ _ _. 1977. Great Lakes Water Quality, 1976. Annual Report, Appendix A. Annual Report of the Water Quality Objectives Subcommittee and the Task Force on the Scientific Basis for Water Quality Criteria. Internatl. Joint Commission, Windsor, Ontario, p.35. Webb, R. G. and McCall, A. C. 1973. Quantitative PCB standards for electron capture gas chromatography. J. Chromatogr. Sci. 11 :366-373. Yoshida, T., Takashima, F., and Watanabe, T. 1973. Distribution of 4C] PCBs in carp. Ambio 2: 111-113.
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NOTE ORGANOCHLORINE CONTAMINANTS IN A SEA LAMPREY (PETROMYZON MARINUS) FROM LAKE ONTARIO
Klaus L. E. Kaiser and Ilze Valdmanis National Water Research Institute Canada Centre for Inland Waters P. O. Box 5050, Burlington, Ontario L 7R 4A6
ABSTRACT. A sea lamprey (Petromyzon marinus) specimen from Hamilton Beach, Lake Ontario, was analyzed for organochlorine pesticide and PCB residues. Contrary to the expectations, the residue levels observed were similar to those found in salmonid species. The concentrations of PCBs, DDT and metabolites, and mirex all exceeded the existing guidelines and proposed water quality objectives. Other organochlorine residues are below such limits, where existing. It is recommended to investigate organochlorine residues in sea lamprey from the Great Lakes in more detail.
INTRODUCTION In the Great Lakes basin, sea lamprey research has primarily dealt with the efficacy of the control measures and the larval state of the lamprey in tributaries. There is little information, however, on the behavior and habitat of the sea lamprey in the adult stage in open lake waters. This lack of information is remarkable in view of some $30 million spent for the lamprey control program since its inauguration. In the same period, largescale environmental surveillance programs of fishes, waters and sediments of the Great Lakes under the auspices of the International Joint Commission (IJC) and other agencies have resulted in a large data base with thousands of observations on contaminants in fish. Thus, it is surprising that not a single report on organochlorine contamination in Great Lakes' sea lamprey can be found in the data base on fish in Ontario waters (OMNR 1977). The report presented here is the result of a detailed investigation of organochlorine residues in a single specimen of sea lamprey from Hamilton Beach, Lake Ontario.
until workup. Solvents were of pesticide grade, glassware was washed with pesticide grade ~olvents and baked at 300°C. After thawing, the lamprey was cut into pieces 2 to 4 cm in length. The pieces were combined and ground with Polytron, Waring, and Virtis blenders which resulted in homogenization of the tissues. However, none of these methods achieved homogenization of the lamprey skin. Therefore, the skin fragments and tissue mixture were ground in a porcelain mortar together with 20 to 30 mesh pre-extracted Ottawa sand (Fisher Scientific Co.) and anhydrous sodium sulfate that had been baked at 550°C. The resulting mixture was divided into four approximately equal portions. Three of these portions were placed in separate Pyrex Soxlet extraction thimbles with sintered glass bases and each was extracted under reflux for 17 hours with an equal volume mixture of hexane and acetone. The three extracts obtained were combined and extracted with one liter distilled water, which had been pre-extracted with hexane. The aqueous phase was separated and re-extracted with 250 mL hexane. The organic phase was extracted with another 750 mL distilled water which was reextracted again with 100 ml benzene after the addition of 500 mL of a saturated aqueous sodium sulfate solution to break the emulsion which had resulted. All aqueous phases were then discarded. The organic phases were combined, dried with
MATERIALS AND METHODS A female sea lamprey (Petromyzon marinus), weighing 350 g, was caught by a diver off Hamilton Beach, Lake Ontario, where it was attached to an instrument at approximately 7.0 m depth, on 12 December, 1976. After removal of kidney and gill samples for other purposes, the lamprey was frozen 234
235
NOTE - ORGANOCHLORINE RESIDUES IN SEA LAMPREY
anhydrous sodium sulfate and concentrated on a rotary evaporator at 40°C to approximately 50 mL. The extract was then transferred to a 100 ml volumetric flask and made up to volume with iso-octane. One mL of the extract (100 mL) was injected onto a high pressure liquid chromatograph with a 1 m x 0.8 cm SS column packed with Porasil A in iso-octane. The column was sequentially eluted at a flow rate of 2 mL/min with 22 mL each of the four solvents: iso-octane, 20 per cent benzene in iso-octane, benzene, iso-octane. The volume of each elutant was reduced to 10 mL in a Vortex evaporator at 40°C and each solution was subjected to gas chromatography on three different stationary phases according to the method of Sampson et al. (1977) described in the methods of organochlorine pesticide analysis in the Analytical Methods Manual, Water Quality Branch, Inland Waters Directorate. With the exception of PCBs, all organochlorine pesticide residues reported were confirmed with the three-column gas chromatographic technique (Sampson et al. 1977). For the calculation of the results, a total weight of 250 g was assumed for the three tissue portions analyzed as the fourth portion was lost and the quantitative extraction of the only partially homogenized lamprey skin was not guaranteed. PCB levels were calculated using the method by Webb and McCall (1973), as modified by Chau and Sampson (1975) for electronic data reduction. RESULTS AND DISCUSSION
The sea lamprey specimen investigated contained eleven organochlorine pesticide contaminants above the quantification limits. The concentrations, calculated on a whole fish wet weight basis, as indicated above, are given in Table 1. In addition, high PCB residues were observed which exceeded the Canadian Food and Drug Directorate guideline of 2 p.g/g in edible portions of fish by a factor of approximately two. Mirex exceeded the U.S. Food and Drug Administration guidelines of 0.1 p.g/g by a similar degree. Mirex, DDT, and PCBs also greatly exceeded the proposed water quality objectives for the Great Lakes (IJC 1976). The residue levels of lindane, dieldrin, and endrin were found to be below the recommended maximum levels for the protection of human consumers of fish. No numerical guidelines are presently set for any of the other organochlorine pesticides observed. The observed residue levels, as shown in Table 1,
TABLE 1. Organochlorine contaminant concentrations in a sea lamprey specimen from Lake Ontario; data on whole fish, wet weight basis. Contaminant
Concentration [p.gJgJ
PCBs p,p'. DDE p,p' - DDD p,p'. DDT
3.62
mirex 'Y-chlordane a-chlordane
HCB dieldrin
a-BHC lindane endrin
1.38
0.25 0.09 0.18 0.17 0.12 0.090 0.082 0.035 0.Ql6
0.008
are quite similar to those of the common teleosts. For example, edible portions of brown trout, chinook salmon, coho salmon, and splake from Lake Ontario have mirex residue means of 0.22, 0.18, 0.17, and 0.16 p.g/g, respectively (Water Quality Board, 1977). For comparison, the mirex concentrations in the investigated whole lamprey specimen was 0.18 p.g/g. Similarly, PCB residues in brown trout, chinook salmon, coho salmon, and lake trout were 5.3, 13.1, 8.4, and 9.4 p.g/g, respectively, in 1975 (Water Quality Board 1976), compared to 3.6 p.g/g in the sea lamprey. Comparable residue levels are also indicated for the other organochlorine contaminants. In contrast to the multitude of data on organochlorine residues in edible portions or whole fish, little is known about their concurrent concentrations in fish blood. Experiments with radioactive PCBs showed quick dispersion of the contaminant within certain fatty tissues without any appreciable concentration of the PCBs in the blood of carp (Yoshida et al. 1973). This observation is supported by the known, extremely low solubility of PCBs in water and as a result, one must question the assumption of the sea lamprey feeding primarily on the blood of the host fishes. Based on the similarity of the residue levels in hosts and lamprey, it appears possible that lamprey take up and digest considerable portions of their hosts' tissues. It may be argued that the analysis of one specimen is of little value is assessing the contaminant burden of that species in the entire lake. There is always a possibility of local contamination in certain nearshore areas, but migratory fish species, which spend a large fraction of their adult life in
KAISER and VALDMANIS
236
the open lake waters, are less likely to be affected by local conditions. Also, it has been found that the observation of an organochlorine contaminant in one specimen can be quite indicative of a lakewide contamination, as was shown for example with the organochlorine contaminant mirex (Kaiser 1974, Water Quality Board 1977). Further, it is known that the ratios of the various contaminant levels are often very similar within one species while the levels may vary with the specimen's size and age (Kelso and Frank 1974, Bache et al. 1972). As a result, the finding of the significant contamination of this sea lamprey specimen by a multitude of organochlorine contaminants, in particular PCBs, mirex, and DDT group residues, should be considered evidence of the contamination of this species in all of Lake Ontario. In consideration of the ecological importance of this species in the Great Lakes, this contamination indicates the need for in-depth studies of the organochlorine residues of sea lamprey in the Great Lakes. Such investigations may lead to a better understanding both of the sea lamprey itself as well as its interaction with preferred salmonid fish stocks. ACKNOWLEDGMENTS The cooperation of Dr. A. Niimi, Dr. P. V. Hodson, and Miss B. Blunt is greatly appreciated. REFERENCES Bache, C. A., Serum, J. W., Youngs, W. D., and List, D. J., 1972. Polychlorinated biphenyl residues: Accumulation in Cayuga lake trout with age. Science, 177: 1191-1192.
Chau, A. S. Y. and Sampson, R. C. J. 1975. Electron cap· ture gas chromatographic methodology for the quantita. tion of polychlorinated biphenyls: survey and compromise. Environ. Lett. 8:89-101. I. J. C. 1976. Proposed new and revised water quality ojbectives. International Joint Commission, Windsor, Ontario, 182 pp. Kaiser, K. L. E. 1974. Mirex: An unrecognized contaminant of fishes from Lake Ontario. Science 185 :523·525. Kelso, J. R. M. and R. Frank. 1974. Organochlorine residues, mercury, copper and cadmium in yellow perch, white bass and smallmouth bass, Long Point Bay, Lake Erie. Trans. Amer. Fish. Soc. 103:577-581. OMNR. 1977. Ontario Ministry of Natural Resources, Fisheries Branch. Contaminants levels in Ontario fish, a data summary. Toronto, Ontario, October 1977. Sampson, R., Valdmanis, I., Larose, R. H., and Wolkoff, A. W. 1977. Unpublished report. Procedure for the quantitative liquid chromatographic separation and cleanup of 18 organochlorine pesticides and PCBs in extracts of water, wastewater, fish or sediment. 1 April, 1977. Water Quality Board. 1976. Great Lakes Water Quality, 1975. Annual Report, Appendix B. Annual Report of the Surveillance Subcommittee. Internatl. Joint Commission, Windsor, Ontario. p. 138. _ _ _. 1977. Great Lakes Water Quality, 1976. Annual Report, Appendix A. Annual Report of the Water Quality Objectives Subcommittee and the Task Force on the Scientific Basis for Water Quality Criteria. Internatl. Joint Commission, Windsor, Ontario, p.35. Webb, R. G. and McCall, A. C. 1973. Quantitative PCB standards for electron capture gas chromatography. J. Chromatogr. Sci. 11 :366-373. Yoshida, T., Takashima, F., and Watanabe, T. 1973. Distribution of 4C] PCBs in carp. Ambio 2: 111-113.
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