The relative importance of accumulation of cadmium by Artemia salina (L.) directly from solution and from ingested food has been studied at 3 cadmium concentrations (0.1, 1 and 10 ppm) under controlled experimental conditions. At each cadmium concentration, A. salina were exposed to cadmium in 4 ways; in solution; in solution in the presence of latex “food” particles; in solution with cadmium-rich Dunaliella tertiolecta as a food source; and to cadmium-rich D. tertiolecta alone. Net accumulation of cadmium by A. salina continued throughout 5 days exposure under all 4 conditions. When the brine shrimp were removed to cadmium-free conditions, their accumulated cadmium concentrations declined and levelled off to a stabilised plateau after 10 days. From consideration of these stabilised levels it was shown that at least 30% of cadmium accumulation directly from solution occurs via uptake through the alimentary tract. The ratio of cadmium accumulated from solution to cadmium accumulated from food was found to be 1:4.9, 1:6.7 and 1:1.1 at 0.1, 1 and 10 ppm Cd exposure, respectively. At lower cadmium exposures uptake from food is the major route for cadmium accumulation, but at higher exposures the cadmium-saturated food source displaced cadmium-rich water from the gut and therefore actually inhibited cadmium accumulation. This study, therefore, concludes that the food chain will be the major source of cadmium as long as the previous trophic level has the ability to accumulate the metal to such an extent as to make it more available to the consumer than by direct uptake from seawater.
KeywordsCadmium Cadmium Concentration Brine Shrimp Dunaliella Cadmium Content
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- Jennings, J.R.: The influence of heavy metals on marine organisms and the transfer of cadmium through a simple laboratory food chain, 210 pp. Ph.D. thesis, University of London 1978. (Unpublished m/s)Google Scholar
- Rice, T.R.: Review of zinc in ecology. In: Radioecology, Proceedings of the First National Symposium on Radioecology, pp 619–631. Ed. by V. Schultz and A.W. Klement: New York: Reinhold 1963. [Proc. natn. Symp. Radioecol. (Oak Ridge)]Google Scholar
- Rogers, A.W.: Techniques of autoradiography, 338 pp. Amsterdam/London/New York: Elsevier Publishing Co. 1969Google Scholar