US EPA

3108485 

Journal Article 

Effects of pesticides on embryonic development of clams and oysters and on survival and growth of the larvae 

Davis, HC; Hidu, H 

1969 

No 

Fishery Bulletin
ISSN: 0090-0656 

67 

2 

393-404 

English 

ZOOR10600026674 

Fifty-two compounds were tested for their effects on embryos of the hard clam, Mercenaria mercenaria, and the American oyster, Crassostrea virginica, and on their larvae. The pesticides included 17 insecticides, 12 herbicides, one nematocide, four solvents, and 18 miscellaneous bactericides, fungicides, and algicides.

Most of the compounds affected embryonic development more than survival or growth of larvae. Some, however, drastically reduced growth of larvae at concentrations that had relatively little effect on embryonic development. It is necessary, therefore, to evaluate the effects of pesticides on all stages of the life cycle of an organism before the pesticide can be considered safe. Nevertheless, differences in toxicity to bivalve larvae among compounds of each category of pesticide are large enough that it should be possible to select compounds to control pest species without serious damage to commercial shellfish.