Isopropyl Cresols

The Food and Drug Administration (FDA) permits the use of Thymol as a direct and food additive (as a flavoring substance) and as an indirect food additiveIndirect food additives are additives that may become part of the food in trace amounts due to its packaging, storage or other handling. For example, minute amounts of packaging substances may find their way into foods during storage. (for use in paper an paperboard in contact with food). The safety of Cresols and Isopropyl Cresols including Thymol has been assessed by the Cosmetic Ingredient ReviewThe Cosmetic Ingredient Review (CIR) was established in 1976 as an independent safety review program for cosmetic ingredients. The CIR Expert Panel consists of independent experts in dermatology, toxicology, pharmacolgy and veterinary medicine. The CIR includes participation by the U.S. Food & Drug Administration and the Consumer Federation of America. (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that Sodium p-Chloro-m-Cresol, p-Chloro-m-Cresol, Chlorothymol, m-Cresol, o-Cresol, Isopropyl Cresols, Thymol, o-Cymen-5-ol and Carvacrol were safe at concentrations up to 0.5% in cosmetics and personal care products; however, the available data were insufficient to support the safety of p-Cresol and Mixed Cresols for use in cosmetic and personal care products.

CIR Safety Review: The CIR Expert Panel concluded that the toxic effects of cresol and isopropyl cresol ingredients were observed at doses higher than would be available from cosmetics and personal care products. In order to ensure that these ingredients are used at a level that would not cause any adverse effects, the CIR Expert Panel recommended an upper concentration limit. Data were available to demonstrate that m-Cresol and o-Cresol when tested at 0.5% do not cause chemical leukoderma (skin whitening). It may be that Sodium p-Chloro-m-Cresol, p-Chloro-m-Cresol, Chlorothymol, m-Cresol, o-Cresol, Isopropyl Cresols, Thymol, o-Cymen-5-ol and Carvacrol do not cause chemical leukoderma at concentrations higher than 0.5%, but data were not available to support that possibility. Therefore, a concentration limitation of 0.5% was chosen to ensure the absence of a chemical leukoderma effect. p-Cresol was shown to cause depigmentation of hair and possibly the skin. In addition, there was a concern that p-Cresol may be a strong allergen. There were insufficient data for the CIR Expert Panel to determine a safe use level that would not sensitize or lighten the skin for p-Cresol and Mixed Cresols (which contains p-Cresol). Therefore, the CIR Expert Panel considered that the available data were insufficient to support the safety of these two ingredients in cosmetics. Studies are needed which would demonstrate a concentrations of use of p-Cresol and Mixed Cresols that would not result in skin whitening.

Link to FDA Code of Federal Regulations for Thymol

• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…
• http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr…

In the European Union, p-Chloro-m-Cresol, Sodium p-Chloro-m-Cresol at concentrations up to 0.2% and o-Cymen-5-ol (4-Isopropyl-m-cresol) at concentrations up to 0.1% are allowed to be used as preservatives (see Annex VI).

Link to the EU Cosmetic Regulation: 
http://europa.eu/legislation_summaries/consumers/product_labelling_and_p…