Microplastics/California Department of Toxic Substances Control: Proposed Addition to the Candidate Chemical List

The California Department of Toxic Substances Control (“DTSC”) is proposing a definition of microplastics, and the addition of microplastics to the Candidate Chemicals List under California’s Safer Consumer Products regulations (“Regulations”). See DTSC Reference Number: R-2023-05R.

The Regulations provide that DTSC may identify and list as a Priority Product one or more product-chemical combinations that it determines to be of high priority.

Microplastics are generally defined as plastic debris less than 5mm in length.

Concerns have been expressed that microplastics:

• Are ubiquitous in the environment.
• Can pose harm because of exposure to a wide range of species living in diverse habitats.
• Can be ingested by humans through drinking water, air, and food.
• Are regularly released into wastewater treatment plants as they are released from clothing from the wash cycle.

DTSC notes that it may add chemicals that exhibit one or more hazard traits and/or environmental or toxicological endpoints to the Candidate Chemicals List by considering certain specified factors including:

• The potential for the chemical to cause or contribute to significant or widespread adverse impacts; and,
• The potential for human or ecological exposures to the chemical.

DTSC states that:

…Following an extensive review of the scientific literature and analysis of the known hazard traits of microplastics, DTSC concluded:

• There is a high potential for animals, humans, and environmentally sensitive habitats to be exposed to microplastics.
• Microplastics have the potential to cause or contribute to adverse impacts for:
  • Sensitive subpopulations,
  • Environmentally sensitive habitats;
  • Endangered or threatened species; or,
  • Environments in California designated as impaired by a California State or federal regulatory agency.
• Microplastics exhibit one or more hazard traits and/or environmental or toxicological endpoints.
• The extent and quality of information available substantiates the existence of potential adverse impacts and exposures of microplastics.

A copy of the Notice of Proposed Action and Initial Statement of Reasons can be found here.