Sodium Benzoate [CAS # 532-32-1] = This is a preservative commonly used in foods, pharmaceuticals and cosmetics. It scores a 3 on skin deep. It is also designated as generally regarded as safe (GRAS) by the FDA. There can be an issue when Sodium Benzoate combines with Ascorbic Acid creating a form of benzene, a known carcinogen. That said, this scenario is typically occurs in diet sodas not cosmetic products. In foods, fats and sugars hinder the formation of benzene and thus is considered safe and usable in foods by FDA.