A Nationwide Outbreak of Alopecia Associated With the Use of a Hair-Relaxing Formulation
September 2000
in “
Archives of dermatology
”
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TLDR A hair-straightening product caused widespread hair loss and scalp injuries, mainly affecting African American women.
A nationwide outbreak of alopecia and scalp injuries was linked to the use of the Rio Hair Naturalizer System, a commercial hair-straightening product. A survey of 464 individuals who reported adverse effects to the FDA in 1994 and 1995 revealed that 95% experienced hair breakage and/or hair loss, with 75% of those losing 40% or more of their original hair. The median time for new hair growth was 8 months, but 9% reported no new growth even 2 years later. The product's pH levels were highly acidic, contributing to the adverse effects. Most affected individuals were African American women aged 15-55.