Towards the development of an alternative analysis method to determine lead in eyeliner cosmetics

Previous research has shown that potentially toxic elements may be present in cosmetic products as impurities or for pigmentation and may be linked to adverse health effects. Yet in low-resource countries where cosmetics hold historical and cultural significance, potentially toxic element contamination in cosmetics is often not well studied or regulated. Current 'gold standard' methods for quantifying these contaminates are inductively coupled plasma - optical emission spectrometry (ICP-OES) and mass spectrometry (ICP-MS). These methods are expensive, time-consuming, and require rigorous sample preparation, making them challenging to perform in low-resource countries. The goal of this research is to develop a field-friendly method of potentially toxic element analysis. Initial studies focused on screening cosmetic samples collected from the low-resource countries; the results showed that lead (Pb) was present in particularly high concentrations. Further analysis showed that 79% of all the collected eyeliner cosmetic samples contained hazardous levels of Pb contamination. Towards the development of a more field-friendly analysis method for Pb contamination, we created and validated a Pb-spiked cosmetic standard that was used to assess different extraction methods. We then optimized an alternative method using citric acid for use with a field-friendly anodic stripping voltammetry analysis method; this method resulted in the detection of 83% of the total Pb present in the fortified standard. However, when this alternative method was used to analyze the collected samples, matrix effects of select cosmetics significantly reduced the Pb detection. Further research will need to be conducted to address the matrix effects of these cosmetics.