Summary As part of a series of non-clinical studies to evaluate the safety of PureSorb-Q TM 40 (Water-soluble type CoQ 10 powder, CoQ 10 content is 40 w/w%; hereinafter referred to as P40), male and female rats were treated orally by gavage with P40 once a day for 91 d, and its repeated dose toxicity was assessed. Control animals were treated with a 0.5 w/v% solution of methylcellulose, the vehicle for P40. Each test group consisted of 6 animals of each sex. No adverse effects of P40 were noted in general signs, body weight, food consumption, ophthalmological examination, urinalysis, hematological examination, blood chemical analysis, necropsy, organ weights, or histopathological examination in animals of either sex. From these results, the no observed adverse effect level of P40 was estimated at 2,000 mg/kg in both sexes of rats under the conditions of the present study, and P40 was confirmed to be a food material whose safety is high.