Temporal and spatial trends of pesticides, PCBs and PCDD/PCDFs in Great Lakes fish communities: 1977--1993
- Department of Fisheries and Oceans, Burlington, Ontario (Canada)
Lake trout (Salvelinus namaycush) and rainbow smelt (Osmerus mordax) have been monitored for whole body contaminant burdens at several open lake sites throughout the Great Lakes annually since 1977. Lake trout, representing a top predator species, were analyzed on an individual basis and all fish were aged. Smelt, as a representative forage species, were analyzed as composites of 5 similar sized fish. There was a consistent basin wide downward trend in whole body burdens of pesticides and total PCBs in both indicator species through to the early 1980`s. This trend was followed by a 2 to 3 year period of modest increases in organic contaminant concentrations at a majority of the monitoring sites. Most recently, significant fluctuations in body burdens have occurred over a shorter time cycle. Supporting data indicate that a reduction in loadings was directly responsible for early declines. Recent fluctuations are now closely linked to alterations of the aquatic community composition and in particular changes in the fish and invertebrate forage base. Analysis of the 17 year database indicates that lake wide total PCB and pesticide concentrations are directly proportional to both industrial and agricultural activities. Thus, fish communities from the lower Great Lakes consistently have body burdens from 2 to 5 times greater than similar communities in the upper lakes. This is consistent with input from potential sources within the various lake basins. PCDD/PCDF congener concentrations and profiles between lake basins are reflective of the significance of either historical pulp and paper mill inputs or chlorophenol production within the system. Both cohort analysis and foodchain contaminant dynamics of pesticides, PCBs and PCDD/PCDFs display significant interlake differences.
- OSTI ID:
- 230846
- Report Number(s):
- CONF-9511137-; ISBN 1-880611-03-1; TRN: IM9623%%156
- Resource Relation:
- Conference: 2. Society of Environmental Toxicology and Chemistry (SETAC) world conference, Vancouver (Canada), 5-9 Nov 1995; Other Information: PBD: 1995; Related Information: Is Part Of Second SETAC world congress (16. annual meeting): Abstract book. Global environmental protection: Science, politics, and common sense; PB: 378 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Historical relationships between organochlorines and stable isotopes in Lake Trout from Lake Ontario
Evaluation of temporal and age-related trends of chemically and biologically generated 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in Lake Ontario lake trout, 1977 to 1993