Accumulation of Trace Metal(loid)s in Fish Muscle Tissue From the Groot Letaba River, South Africa

Abstract

Many elements become toxic when they exceed certain concentrations in the environment. In the aquatic ecosystems, they can be accumulated in the biota such as fish and may be toxic to humans upon consumption. This study assessed bioaccumulation of the following elements; arsenic, cadmium, chromium, copper, lead and Zinc in the muscle tissue of ten common consumable fish species from Groot Letaba River in South Africa and assessed the potential human health risks. In the water, only zinc exceeded the recommended safe limit. However, most of the elements were found to be significantly accumulated in the sediments and the muscle tissue of the fish species. The elements were more accumulated in the omnivorous and some predatory fish species than the herbivores. Concentrations of As, Cd, Cr and Zn in the fish muscle tissue were above the recommended food safety guideline values, indicating a potential health risk to consumers, especially As at Site 1 and Zn at Site 4. There is a need therefore for continuous monitoring of trace metals and metalloids in the river in order to ensure the safety of aquatic organisms and humans who rely on the river.