Effects of aqueous stable fullerene nanocrystal (nC60) on copper (trace necessary nutrient metal): Enhanced toxicity and accumulation of copper in Daphnia magna.

•nC60 lowered the LC50 enhanced the 48h-toxicity of copper ions on D. magna.•The increased Cu2+-ATPase activity indicated nC60 enhanced the Cu2+ transport.•nC60 acted as a Cu2+carrier to enhance the copper accumulation in D. magna.•The absorption and desorption may account for the interaction between nC60 and Cu2+.