BIOACCUMULATION OF CHROMIUM AND NICKEL IN THE TISSUES OF BARBUS-MAREQUENSIS SMITH,A., 1841 FROM THE LOWER OLIFANTS RIVER, MPUMALANGA

Bioaccumulatlon of chromium and nickel in selected tissues and organs of the freshwater fish Barbus marequensis was investigated. According to the monthly data, the blood accumulated the highest amount of chrom ium, followed by the bile and vertebrae, while the skin accumulated th e lowest amount. Nickel mainly accumulated in the blood, followed by t he vertebrae and gills, while the lowest nickel concentrations occurre d in the fat tissue. Although significant differences (p less than or equal to 0,05) between localities were detected, no definite trend as to where the highest bioaccumulation had occurred could be established . The levels in the tissues and organs of B. marequensis suggested no serious chromium or nickel pollution in the study area.