ISSN:
1573-5133
Keywords:
Persistent pesticide
;
Industrial contaminants
;
Restrictions
;
Bioaccumulation
;
Fish Species-Trophic levels
;
Lake system
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Synopsis Lake Simcoe located in the central Ontario plain has four major streams draining the watershed. Persistent organochlorine insecticides were used in the basin for mosquito control and agricultural production until restricted. Methyl mercury compounds have been phased out and a voluntary restriction occurred for PCB. Ten species of fish were collected between 1970 and 1976 for organochlorine and mercury analysis. ΣDDT residues significantly declined between 1970 and 1975–76 in all species except small Stizostedion vitreum vitreum and large Salvelinus namaycush. Eggs taken 1975–76 from small S. namaycush had ΣDDT residues below the critical level reported for the production of viable offspring, but this was not so for large members. HEOD residues between 1970 and 1975–76 significantly declined in five species, showed no change in two, whereas in two species the Larger members of one had Lower residues and the smaller members of the other showed no change. PCB residues declined.in all species except the larger Perca flavescens. Chlordane and heptachlor-epoxide were identified in S. namaycush for the first time in 1975–76. Mercury residues showed no change between 1970 and 1975–76 in five species, it declined in two species and increased in small S. v. vitreum. Correlations existed between Levels of organic contaminant and Lipid content of fish especially in the immediate post period of their use. Where the increasing Lipid content was associated with an increasing trophic level a preypredator relationship existed for contaminant accumulations. However, where Lipid contents were Low, no correlation appeared to exist in the prey-predator.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00001453
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