By Ma’ayan Tzur
Almost every time I walk to 245 Lexington for class, I pass Murray Nail & Spa on 34th Street. There are thousands of other nail salons in the U.S. and even more throughout the world. In fact, 85-90% of women use nail care products globally, according to a study referenced in Reinecke and Hinshaw’s 2020 article about women’s nail health. However, nail salon workers in the Murray Hill salon or globally may not realize that working in a nail salon could increase their risk of developing multiple myelomas. Moreover, 85-90% of women who use nail care products probably do not know that the chemicals in nail polish and related products can be harmful to their genes, cause cancer, and/or affect their reproductive systems.
For example, formaldehyde and toluene, popular chemicals found in nail polish and products in nail salons, may cause genetic mutations and be reproductively harmful. One study exposed TA98, TA100, TA102, TA1535, and TA1537 bacterial strains to different concentrations of gaseous formaldehyde and toluene for different amounts of time, and performed Ames tests using these strains. The study found revertants in TA100 exposed to 0.035ppm of gaseous formaldehyde, a low concentration, and significantly more revertant colonies when TA100 without S9 activation was exposed for 1.5-8 hours to 50 ppm of gaseous toluene. Also, according to a review article, formaldehyde was frequently associated with affecting the female reproductive and endocrine system.
Additionally, other studies found micronuclei in in vivo mouse bone marrow injected intraperitoneally with different concentrations of toluene. In other studies, chromosomal aberrations were found in in vivo rat bone marrow exposed to different concentrations of toluene via inhalation, intraperitoneal injection, and subcutaneously. Toluene has also been correlated with shorter pregnancies and decreased fetal growth, as well as with spontaneous abortions.
Other potentially harmful ingredients in nail polish and nail products are Methoxyisopropanol and Dibutyl Phthalate (DBP). In one study, V79 cells exhibited greater sister chromatid exchange after exposure to 100 mM of Methoxyisopropanol. Additionally, another study that treated cultured Bovine peripheral lymphocytes with different concentrations of DBP showed an increase in micronuclei with increasing DBP concentration compared to a control. Also, DBP may pose a danger to reproductive health. According to a review article, phthalates, especially DBP and DEHP, di (2- ethylhexyl) phthalate, may affect the male reproductive system at current levels of human exposure. Phthalates also seemed to correlate with a lower sperm count, and research showed that animals exposed to DBP exhibited increases in fetal reabsorption and miscarriages.
Exposure to chemicals in nail polish may also increase a person’s risk for cancer. For example, many nail lacquers contain a chemical called Propylene glycol mono-t-butyl ether. In a study published in 2004, male and female rats and mice were exposed to propylene glycol mono-t-butyl ether via inhalation in concentrations of 75, 300, or 1,200 ppm, and tissues were analyzed from over 40 sites in each animal. Female and male mice were found to have many more liver tumors than in untreated controls also analyzed. However, female rats in the exposed group were not found to have more tumors than the control group, and while male rats were found to have more liver and kidney tumors than male rat controls, it is unclear if those results were significant. These animals were exposed to the propylene glycol mono-t-butyl ether for six hours per day, five days a week for two years, and nail technicians work similar hours, or more, exposed to the same chemical. Therefore, it is concerning that exposed mice were found to have more liver tumors, as it could mean that nail workers could have a higher chance of developing liver cancer, too.
Furthermore, the International Agency for Research on Cancer labeled formaldehyde (commonly found in nail polish) as a Group 1 carcinogen. Additionally, The American Journal of Industrial Medicine analyzed different occupations in a cancer registry and found more cases of multiple myelomas in manicurists, cosmetologists, and hairdressers. They hypothesized this to be due to exposure to the chemicals in nail polish products, since, as mentioned previously, they have been found to cause mutations.
Even though chemicals in nail polish and exposure in nail salons can potentially cause DNA damage, cancer, and have detrimental effects on the reproductive system, not much has been done to protect the general public or nail technicians, who may be at higher risk due to prolonged exposure. For example, in a focus group with thirteen Midwestern nail technicians, it came to light that there was a “lack of standardized policies, regulations, [and] education/training,” “inadequate knowledge on exposures and safety protocols”, and “unsafe nail products.” Therefore, it is important to raise awareness of the potentially harmful chemicals in nail polish, and ensure only safe ingredients are being used. Additionally, nail technicians should not work while pregnant, and research should continue to determine safe levels of exposure to these chemicals. More research should also be done about potential precautions that could help protect people from these chemicals, such as wearing masks and/or gloves in nail salons, and reducing nail technicians’ work hours. For now however, it might be best to avoid working in a nail salon altogether.