Bioaccumulation of zinc and lead in selected tissues and organs of the freshwater crab, Potamonautes warreni

Abstract

Potamonautes warreni collected from a wetland affected by effluents from industries, mines and a number of sewage purification works had variable concentrations of zinc and lead in their carapace, gills, gonads, midgut glands and muscle tissue. The highest mean concentrations of zinc (112.9 ± 413.9 μg·g −1 wet wt.) and lead (86.6 μg·g −1 wet wt.) were recorded in the gonads and the carapace tissue, respectively. No seasonal variation in the bioaccumulation of zinc was observed, while a significant rise in the bioaccumulation of lead was observed for some periods. Immature and mature crabs generally had similar zinc concentrations per equivalent mass, but the lead concentrations for the midgut gland muscle in immature crabs were significantly higher than in mature crabs. The significance of the data is discussed.