Study of Bacterial Contaminants in Local as Well as Branded Lipsticks before and after Consumer Use

Lipstick, is a face-care cosmetic that commands a unique market as it is one of the most affordable cosmetic products available with as many as 80% of women using it regularly. Lipsticks need not be sterile and may contain low levels of microbial load during or prior to use. Lipsticks are often inadvertently consumed by the users and hence it is imperative that the health regulators have a microscopic look at the ingredients as well as the microbial flora (if any) in the lipsticks. This study was performed to determine the bacterial load in terms of colony forming units in addition to the type and concentration of a paraben preservatives used in lipsticks. Twelve brands of lipsticks were selected for the study of which, four were taken from the Indian market (unused samples), four (Multinational brands) used for over a year and four (multinational brands) used for over two years. The bacteria in these samples were isolated and identified by 16s rDNA sequencing and the amount of preservatives quantified by HPLC (High Performance Liquid Chromatography). Our results indicated that all the products were contaminated to varying degrees depending on their usage. Besides the skin normal flora Staphylococci, gram negative organisms of Pseudomonas, Proteus, Morganella, Providencia species also featured prominent among the isolates. The HPLC data obtained indicated the presence of parabens at a concentration of 2740 ppm and 6960 ppm which is higher than 100-3000 ppm of parabens as stated by the US-FDA. The work cautions the end user about the quality of lipsticks a widely used cosmetic product.