California’s Department of Toxic Substances Control (DTSC) has proposed listing nail products containing methyl methacrylate (MMA) as its latest Priority Product under its Safer Consumer Products regulation.

DTSC has gone after nail products before–nail products with toluene are already a proposed Priority Product awaiting adoption by the California Legislature.  

If the newest proposal is adopted, responsible parties will need to remove impacted products from sale in California or undertake an alternatives analysis in order to continue selling in California.

The California Safer Products Regulation

As a refresher, the Safer Consumer Products regulation restricts the use of certain chemicals when used in specified products, based on various human health and the environmental risk factors. These product-chemical combinations are called “Priority Products.”

When DTSC finalizes a Priority Product, manufacturers, distributors, and retailers must either conduct an alternatives analysis of the chemical, or remove the product from sale in California. The alternatives analysis can lead to identification of a safer alternative, or determine that there is no safer alternative–at which point DTSC can impose restrictions on use.

What is methyl methacrylate?

MMA is a volatile monomer used in a number of nail products. According to DTSC, MMA can be released from these products into air and can be inhaled. Dermal and oral exposure to MMA from nail products can also occur, either directly from the product or as a residue/contaminant in polymers made using MMA (e.g., acrylic nails). MMA is not noted as a carcinogen or reproductive toxin a la Proposition 65, but it can be a skin and respiratory irritant.

DTSC also notes that MMA has been detected in retail nail products for home use as well as in indoor air in nail salons. The Food and Drug Administration undertook a campaign to remove nail products containing 100 percent MMA from the market in the 1970s (via court proceedings—there is no formal FDA regulation on MMA). In 2014, California’s Board of Barbering and Cosmetology prohibited the use of MMA-containing nail products in licensed hair and nail salons and cosmetology schools.

Despite these significant historical restrictions on MMA, DTSC stated that “MMA continues to be detected in indoor air in nail salons. MMA exposure has been linked to adverse health effects including dermal toxicity and respiratory tract effects.

Next Steps

DTSC has released a draft technical report that discusses the scientific basis for listing nail products containing MMA. A public workshop will be held on February 24, 2020.

This proposal is only the beginning of the process. Assuming DTSC adopts this as a Priority Product, it then has to go through the rule making process to be an official regulation. This could take 12 months, and likely more.