Presented at the Wildlife Mercury Conference, Fairfax, Virginia, USA, April 12–13, 1996.
Methylmercury chloride and selenomethionine interactions on health and reproduction in mallards†
Article first published online: 26 OCT 2009
Copyright © 1998 SETAC
Environmental Toxicology and Chemistry
Volume 17, Issue 2, pages 139–145, February 1998
How to Cite
Heinz, G. H. and Hoffman, D. J. (1998), Methylmercury chloride and selenomethionine interactions on health and reproduction in mallards. Environmental Toxicology and Chemistry, 17: 139–145. doi: 10.1002/etc.5620170202
- Issue published online: 26 OCT 2009
- Article first published online: 26 OCT 2009
- Manuscript Accepted: 15 JUL 1997
- Manuscript Received: 20 AUG 1996
Adult mallards (Anas platyrhynchos) were fed a control diet or diets containing 10 ppm mercury as methylmercury chloride, 10 ppm selenium as seleno-DL-methionine, or 10 ppm mercury plus 10 ppm selenium. One of 12 adult males fed 10 ppm mercury died, and eight others suffered paralysis of the legs by the time the study was terminated. However, when the diet contained 10 ppm selenium in addition to the 10 ppm mercury, none of 12 males became sick. In contrast to the protective effect of selenium against mercury poisoning in males, selenium plus mercury was worse than selenium or mercury alone for some measurements of reproductive success. Both selenium and mercury lowered duckling production through reductions in hatching success and survival of ducklings, but the combination of mercury plus selenium was worse than either mercury or selenium alone. Controls produced an average of 7.6 young per female, females fed 10 ppm selenium produced an average of 2.8 young, females fed 10 ppm mercury produced 1.1 young, and females fed both mercury and selenium produced 0.2 young. Teratogenic effects also were worse for the combined mercury plus selenium treatment; deformities were recorded in 6.1% of the embryos of controls, 16.4% for those fed methylmercury chloride, 36.2% for those fed selenomethionine, and 73.4% for those fed methylmercury chloride and selenomethionine. The presence of methylmercury in the diet greatly enhanced the storage of selenium in tissues. The livers of males fed 10 ppm selenium contained a mean of 9.6 ppm selenium, whereas the livers of males fed 10 ppm selenium plus 10 ppm mercury contained a mean of 114 ppm selenium. However, selenium did not enhance the storage of mercury. The results show that mercury and selenium may be antagonistic to each other for adults and synergistic to young, even within the same experiment.