Survey of bacteriological contamination of cosmetic creams in Iran (2000)

The bacteriological quality of a variety of unused and used cosmetic creams was investigated. A 1-g sample from each product was aseptically placed in 9 ml of sterile Tween-peptone diluent, and 10-fold serial dilutions were prepared. The pour plate technique was used for aerobic bacterial colony counts, and microorganisms that grew in the culture were identified. The incidence of contamination by Gram-positive Bacilli, Staphylococcus aureus and non Escherichia coli Gram-negative organisms was found to be higher for used cosmetic creams (54%, 38% and 8%, respectively) than for unused creams (38%, 25% and 0%, respectively). Viable microorganisms were not recovered from 17% of the unused items whilst only 10% of the used creams did not contain viable microorganisms. The significance of the results is discussed and the importance of adopting suitable quality control guidelines is highlighted.