Comparison of the cytotoxic responses of Escherichia coli (E. coli) AMC 198 to different fullerene suspensions (nC60)

Fullerenes are set to be produced on an industrial scale in anticipation of their wide applications. This calls for research on their environmental and health impacts. This study investigates and compares the cell toxicity of different aqueous fullerene aggregates. Popular C(60) dispersal methods were used to prepare four types of nC(60) aggregates. These aggregates were tested against the indicator species Escherichia coli (E. coli) AMC 198. With aggregates of around 150 nm in diameter, the THF/nC(60) suspension was very toxic and gave rise to a half maximal effective concentration (EC(50)) of 0.54 mg L(-1) in E. coli. By contrast, the Tol/nC(60) suspension exhibited a cytoprotective role while the Aqu-N(2)/nC(60) and Aqu-O(2)/nC(60) suspensions enhanced the metabolism of E. coli. Although some toxicants, such as THF and THF-peroxide, were introduced into the THF/nC(60) suspension during the dispersion, the toxicity of nC(60) itself cannot be neglected.