Objective: To study the long-term outcome of adverse effects reported by pe
rsons who used a commercial hair-straightening product known as the Rio Hai
r Naturalizer System (World Rio Corporation).
Design: Survey of individuals who contacted the Food and Drug Administratio
n in 1994 and 1995 to report adverse effects linked to using the product.
Setting: Persons residing in the United States.
Patients: A total of 464 (59% of 790 eligible) patients who returned a comp
leted questionnaire.
Main Outcome Measures: Adverse effects associated with using the Rio Hair N
aturalizer System products (neutral or color enhancer).
Results: Ninety percent of respondents were African American women between
the ages of 15 and 55 years. The most common complaints associated with the
use of the products were hair breakage and/or hair loss, reported by 95% o
f respondents. Three quarters of those experiencing hair loss reported losi
ng 40% or more of their original hair. The median time between the loss of
original hair and the growth of new hair was 8 months; however, 40 (9%) res
pondents reported having no new growth at the time of completing the survey
, some 2 years after using the product. When mixed according to package ins
tructions, the mean pH of a sample of 20 neutral product kits tested was 1.
39 (range, 1.1-3.15). For the 21 color-enhancer products tested, the mean p
H was 2.82 (range, 2.29-3.08).
Conclusion:: A nationwide outbreak of alopecia and scalp injuries involving
tens of thousands of women land some men) occurred following the marketing
of a chemical hair-relaxing product. Most of those affected reported subst
antial hair loss,with a majority indicating growth of new hair that was abn
ormal in both quantity and quality.