No convincing effects on reproduction or on offspring development were seen in rats given ESBO by stomach tube during mating and pregnancy. There was no evidence of carcinogenicity in rats given ESBO in the diet or (in a limited study) in mice treated by the dermal route. ESBO did not damage the chromosomes or induce mutations in mammalian cells in culture. In bacterial (Ames) tests there was no indication of mutagenicity.