SYNERGISTIC EFFECTS OF TEMPERATURE - OXYGEN AND WATER-FLOW ON THE ACCUMULATION AND TISSUE DISTRIBUTION OF MERCURY IN CARP (CYPRINUS-CARPIO L)

The separate and interacting effects of three environmental parameters (temperature, oxygen concentration, water flow) on the accumulation a nd tissue distribution of mercury were studied with yearling carp in a continuous flow system with a concentration of 0.5 mu g HgCl2 L(-1). All 8 combinations of two levels of each environmental factor were tes ted (10 and 20 degrees C; 4.5 and 9.3 mg O-2 L(-1), 0 and 10 cm s(-1)) . Four organs were assayed: gill, kidney, liver, and muscle. In all te sts the accumulation was highest at low O-2 concentrations. Increased water flow contributed to higher levels of mercury in all organs excep t kidneys. At high temperatures accumulation was increased in kidneys and livers, and decreased in gills. The combination of low O-2 and wat er flow caused the highest accumulation in all organs. An ANOVA analys is showed that there were several synergistic interactions, especially between oxygen and water flow.