Can Lemna minor mitigate the effects of cadmium and nickel exposure in a Neotropical fish?

We aimed to evaluate if Lemna minor can mitigate the observed effects of cadmium (Cd) and nickel (Ni) exposure in Prochilodus lineatus. Fish were exposed for 96 h to 20 mu g L-1 of Cd, 1.5 mg L-1 of Ni, or to a mixture of these two metals. In all tests, one group was exposed to the metals with duckweed on the water surface, and other group was exposed only to the metals, without plants. After each exposure, samples of P. lineatus tissues were collected to evaluate multiple biomarkers. Duckweed prevented bioaccumulation in some fish tissues and attenuated changes in acetylcholinesterase activity, increases in erythrocytic nuclear abnormality frequency, and hyperglycemia. However, the changes in plasma ion concentrations, reduction in activity of ion transport enzymes, and histological damage were not mitigated. Therefore, we concluded that L. minor partially attenuates the effects caused by Cd and Ni exposure.

Automated summary

The aim of this study was to evaluate the effects of duckweed (Lemna minor) on Prochilodus lineatus exposed to cadmium and nickel. The results showed that duckweed partially attenuated some adverse effects of cadmium and nickel, such as reducing acetylcholinesterase activity, decreasing erythrocytic nuclear abnormality frequency, and alleviating hyperglycemia. However, duckweed did not mitigate changes in plasma ion concentrations, reduction in activity of ion transport enzymes, and histological damage.