A regulatory compliant short-term oral toxicity study of soluble [60]fullerenes in rats

Thirty-eight years after its discovery, the safety of [60]fullerene (C60), the most abundant fullerene with many potential applications, particularly in oxidative stress-related medicine, remains controversial. This is mainly due to the alleged dangers of C60 nanomaterial, which are regularly supported by some publications. While several academic studies have confirmed the safety of C60 in various experimental models, it is well known that C60 aggregates can carry toxic elements. Meanwhile, countless websites offer C60-oily solutions to consumers, without any regulatory consideration. Therefore, an officially certified toxicity study is urgently needed to avoid any public health problems. In this context, we report on the first certified short-term oral toxicity study of soluble C60, designed according to the guidelines of the Organization for Economic Cooperation and Development, with a deviation in the duration (2 weeks instead of 4 weeks) accepted by the U.S. Food and Drug Administration. The results of this study, conducted in an independent accredited European Laboratory, clearly show that C60 in soluble form (0.8 mg/ml of extra virgin olive oil), administered at the highest possible dose of 3.8 mg/kg body weight/day, did not cause any adverse effects in rats after 14 days of daily oral administration. This report should settle the debate on the acute oral toxicity of C60 and pave the way for further preclinical studies. The study is accompanied by a comprehensive report that includes documentation of the raw data.