Cadmium uptake by Ceriodaphnia dubia from different exposures: relevance to body burden and toxicity.
Uptake of cadmium from water by freshwater animals has been well documented. However, little attention has been given to the importance of dietary and combined exposure as the source for uptake. In the present study, we compared cadmium uptake from waterborne (water-only), dietary (food-only), and combined (water plus food) exposures on the freshwater cladoceran Ceriodaphnia dubia. Major test end points included cadmium whole-body burdens, feeding rate, and reproduction. The C. dubia three-brood reproduction tests were conducted according to U.S. Environmental Protection Agency methods. The results indicated that cadmium was accumulated from both water and diet. Whereas the results showed that uptake from water was more rapid than uptake from diet, both uptakes occurred independently, and cadmium concentrations in C. dubia were additive from both sources. Furthermore, the present study found cadmium trophic transfer between primary producers (i.e., Pseudokirchneriella subcapitata) and primary consumers (i.e., C. dubia). Feeding rate was reduced from all avenues of exposure. Feeding reduction in combined exposure was affected additively by waterborne and dietary cadmium. Also, reductions in neonate production were observed after exposure to all three exposure types. Both body burden and reduced feeding affected C. dubia reproduction. These results indicate the importance of both waterborne and dietary cadmium exposures as the sources for metal uptake and toxicity.
Sofyan
Agus
A
Department of Biology, University of Kentucky, Lexington, Kentucky 40506, USA. asofy0@uky.edu
Rosita
Gina
G
Price
David J
DJ
Birge
Wesley J
WJ
D000818:Animals; D001822:Body Burden; D002104:Cadmium / Q000032:analysis / Q000493:pharmacokinetics* / Q000633:toxicity; D033361:Cladocera / Q000378:metabolism*; D004781:Environmental Exposure; D005247:Feeding Behavior; D005618:Fresh Water; D012098:Reproduction; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics
D014874:Water Pollutants, Chemical; D002104:Cadmium