Abstract
Conclusion
In a 1996 safety assessment of 4-chlororesorcinol, the Cosmetic Ingredient Review (CIR) Expert Panel stated that this ingredient is safe as used in hair dye formulations. 1 The Expert Panel reviewed newly available studies since that assessment along with updated frequency and concentration of use information (Table 1). 2 –5 The Expert Panel determined to not reopen this safety assessment and confirmed that 4-chlororesorcinol is safe in the present practices of use and concentration in hair dye formulations.
Abbreviation: NR, not reported.
aBecause each ingredient may be used in cosmetics with multiple exposure types, the sum of all exposure type uses may not equal the sum total uses. Totals = rinse off + leave on product uses.
Discussion
The Expert Panel reviewed new data that were published in the opinion released by the European Commission’s Scientific Committee on Consumer Safety (SCCS) in 2010, which determined that this ingredient was not a health risk, apart from sensitization, at a maximum concentration of 2.5%.2 The Expert Panel noted that use of 4-chlororesorcinol in hair dyes has increased from 33 uses to 210 and that the current use concentration is up to 2%, which is higher than the 1% concentration previously reported on but below the SCCS limit. 3,4
In considering hair dye epidemiology data, the CIR Expert Panel concluded that the available epidemiology studies are insufficient to conclude there is a causal relationship between hair dye use and cancer or other toxicologic end points, based on lack of strength of the associations and inconsistency of findings. Use of direct hair dyes, while not the focus in all investigations, appears to have little evidence of any association with adverse events as reported in epidemiology studies. A detailed summary of the available hair dye epidemiology data is available at http://www.cir-safety.org/findings.shtml.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The articles in this supplement were sponsored by the Cosmetic Ingredient Review. The Cosmetic Ingredient Review is financially supported by the Personal Care Products Council.