Safety Considerations for Shampoos and Conditioners

Other cosmetic ingredients, cited in the literature for phototoxic reactions, are 6-methyl coumarin (formerly used as a fragrance component of sun protection and facial products) and halogenated salicylanilides (previously used in antibacterial products such as deodorant soap bars) [188]. 

Shampoos and conditioners are among the safest consumer products sold today when used for their intended purpose and in the manner described on the package label. Cautionary eye warning labels appear on most medicated products and on some cosmetic brands, attesting to the fact that eye irritation can occur if some products accidentally drain or spill into the eyes. Warnings against internal consumption also appear on many shampoo labels and on a few creme rinses or hair conditioners nevertheless, many conditioners contain no cautionary warnings because they are mild and of such low toxicity. 

Bergfeld [191] has reviewed the most frequent adverse effects of hair products from patients at the Cleveland Clinic Dermatology Department over a 10-year period and has found relatively few adverse effects from shampoos— the majority of these are due to sensitization rather than to irritation or hair breakage. Furthermore, Bergfeld attributes these few adverse effects either to preservatives or medicated ingredients of these products rather than to the active ingredients. 

Ishihara [192] surveyed five large hospitals in Japan for contact dermatitis in 1970. Only 0.2% of the cases of the total number of outpatients at all dermatologic clinics were admitted for adverse reactions to any hair preparations. Only 0.008% of these adverse reactions were due to shampoos, and these few cases involved contact dermatitis. From these results, Ishihara concluded that most cases of contact dermatitis from shampoos and conditioners are not serious enough to be treated in a hospital. 

Cosmetic and Toiletry Formnlations, 2nd ed., Noyes Pnblications, Park Ridge, NJ (1989). 

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