The aromatic alcohol Phloroglucinol is used in several hair dyes and colors as an antioxidant and hair colorant. Current data on use concentrations was not available. In rats, Phloroglucinol has an LD(50) of 5.2 g/kg. Subcutaneous injections of unrefined 0.05 M and 0.01 M solutions of Phloroglucinol caused positive dermal reactions in guinea pigs at both activation and challenge. At a concentration of 3.0 mg/ml, Phloroglucinol induced Trp(+) revertants in Saccharomyces and induced chromosome breaks in CHO cells, with and without metabolic activation. These data are not sufficient to demonstrate the safety of Phloroglucinol. Additional data are needed, including information on purity/impurities; types of cosmetic products in which and the typical concentrations at which the ingredient is used; 28-day dermal toxicity study in animals, and depending on the results, dermal absorption, metabolism, and distribution data may be needed; and, if significantly absorbed, dermal reproduction and developmental toxicity (including teratogenicity) data may be needed; human skin irritation data; data from two different genotoxicity assays (one using a mammalian system); and, if the genotoxicity studies are positive, data from an animal carcinogenicity study done by NTP methods is needed. On the basis of the available data, it cannot be concluded that Phloroglucinol is safe for use in cosmetic products.