Alleviative effects of C60 on the trophic transfer of cadmium along the food chain in aquatic environment

C60 could enhance the accumulation of pollutants in organisms, but their effects on higher trophic levels remain unknown. In the present study, the transfer of C60 from Daphnia magna to zebrafish (Danio rerio) and its effects on Cd transfer were investigated. The results showed that C60 could be transferred from D. magna to zebrafish through dietary exposure and accumulate mainly at intestines, but biomagnification was not observed. The presence of C60 promoted accumulation of Cd in D. magna. However, it decreased Cd burden in the higher trophic level (zebrafish), displaying an alleviative effect on the trophic transfer of Cd along the food chain. To explore the underlying mechanisms, the release of Cd from D. magna in digestive fluids and changes of zebrafish digestive physiology were further investigated. The results showed that C60 did not inhibit Cd release from D. magna, but stimulated the digestive tracts of zebrafish to excrete Cd earlier and in a greater amount, which consequently lowered assimila...