Not storing makeup properly and using out-of-date cosmetics can result in infection, said dermatology experts at Baylor College of Medicine in a report in the journal Cosmetic Dermatology.
Dr. Ramsey Markus, professor of dermatology and an author of the study, said that of 19 cosmetic samples tested in the study, six, or 31.5 percent, were contaminated with bacteria.
“Some samples even contained a type of staph,” said Markus, also director of laser surgery and dermatology at Baylor.
Tests of the 19 cosmetic samples showed that nearly one-third contained common bacteria, including Staphylococcus aureus, Streptococcus pneumoniae and Staphylococcus epidermidis.
“While these can sometimes be found in cultures of normal skin, they are potentially dangerous for those who are in immune-compromised states or have a compromised skin barrier,” Markus said. “Staph and strep can lead to infected hair follicles and cellulitis.”
According to the results, cosmetic products used on a semi-regular to daily basis can be a source of infection. Markus attributes this to certain factors that can influence and contribute to the accumulation of bacterial organisms over time in the products.
These factors include:
- Water content
- Antimicrobial ingredients
After buying cosmetics, keep the products properly sealed when not in use to protect against airborne germs. Mascara should be switched out at least every three months, while other cosmetic products should be kept for no longer than six to 12 months. The older a product is, the more time bacteria has to grow in it, Markus said.
“We want to remind the public that there are unseen potential dangers growing in makeup and that the cosmetics they use daily could be a source of infection,” he said.