Determination of Cr(VI) in cosmetic products using ion chromatography with dynamic reaction cellinductively coupled plasma-mass spectrometry (DRC-ICP-MS)

摘要

The chromium(VI) salts are possible contaminants of the chromium(III) pigments used as colorants in face powder and eye shadow preparations. The use of products containing these contaminants poses acute risks for sensitization and contact allergies. Usually, in cosmetics, the levels of hexavalent chromium are very low and should not lead to skin sensitization. However, if a consumer has already been sensitized to Cr(VI) from other sources, the low concentration permitted in cosmetics could arise allergic reactions. In addition to the effect allergenic compounds of Cr(VI) can cause chronic toxicity and have been classified as carcinogenic to humans (IARC). An analytical method to analyze trace levels of chromium(VI) in cosmetic products was developed in this study. The method is based on an extraction of the chromium(VI) from the sample using alkaline extraction in according to method US EPA 3060A developed for soil samples. The Cr(VI) specie present in the extracts were separated by ion chromatography system (IC) and detected using dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS). This method has a limit of quantification for chromium(VI) of 0.11 mg kg(-1), an average recovery of 106%. The precision of the method was calculated as 13.2% and 11.5% for 10 ng mL(-1) and 20 ng mL(-1) of Cr(VI) respectively. Moreover the method shows that the Cr(VI) is stable during the extraction and analytical phases. We applied the optimized method to analyse 4 eye shadows and 1 face powder. One out of 4 of the eye shadow products contained more than 5 mg L-1. This value is higher than the threshold limits for allergic reactivity to Cr(VI).