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Quaternium-15 is an antimicrobial agent used in cosmetics as a cosmetic preservative and antistatic agent. Little systemic toxicity was reported in most single-dose or repeated-dose animal studies. Quaternium-15 was an oral teratogen, but not a dermal teratogen, in rats at doses that exceeded the expected cumulative exposure from cosmetics. The frequency of sensitization increased in North America but not in Europe, where Quaternium-15 is used less often. In almost all animal and human studies, Quaternium-15 at 0.2% was not a sensitizer. The weight of evidence suggested that a 0.2% concentration is not a sensitizer and that cosmetic products containing Quaternium-15 up to that level are safe.
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Becker et al. (2010) studied this question.
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