6PPD.  6PPD is used as an antioxidant, antiozonant, and polymer stabilizer for rubber products.  Many vehicle tires contain 6PPD to prevent them from breaking down due to reactions with ozone and other compounds.  When 6PPD reacts with ozone in the air, it forms 6PPD-quinone (6PPD-q).  As tires wear down through contact with roads, 6PPD-q is released.  Stormwater can transport 6PPD-q from roads into streams and other water bodies, which may expose aquatic organisms to the particles.  Some scientific literature and studies link Coho salmon mortality to 6PPD-q in stormwater runoff following only limited exposure.

Safer Products for Washington.  In 2019, the Legislature established an administrative process for the Department of Ecology (Ecology) to regulate priority chemicals in priority consumer products, referred to as Safer Products for Washington (SPWA).  Under SPWA, certain chemicals were initially defined as priority chemicals, including Perfluoroalkyl and polyfluoroalkyl substances (PFAS chemicals), phthalates, phenolic compounds, PCBs, and certain flame retardants.  Every five years, according to a specified schedule, Ecology, in consultation with the Department of Health, must report to the Legislature its decision to designate at least five priority chemicals meeting certain criteria.

Every five years, according to a specified schedule, Ecology must also:

• identify priority consumer products that include priority chemicals, taking into consideration specified criteria;
• determine regulatory actions for the priority chemicals contained in priority consumer products; and
• adopt rules implementing those regulatory actions.

Regulatory actions may include: (1) a determination that no action is needed; (2) require manufacturers to provide notice of the use of a priority chemical or class of priority chemicals; or (3) restrict or prohibit the manufacture, distribution, sale, or use of a priority chemical or class of priority chemicals in a consumer product.  Chemical restrictions require that safer alternatives are feasible and available.

The designation of priority chemicals and priority consumer products, and the determination of regulatory actions, do not take effect until the adjournment of the regular session immediately following such designation or determination.

On May 31, 2023, Ecology adopted rules requiring manufacturers of consumer products to restrict or report on PFAS, ortho-phthalates, phenolic compounds, and certain flame retardants in specified priority consumer products.  These rules took effect July 1, 2023, concluding the first cycle of SPWA.  The first deadline of the second cycle of SPWA is June 1, 2024, by which Ecology must identify at least five additional priority chemicals.  In June 2023, Ecology submitted a draft identification of priority chemicals to the Legislature, which identified seven new priority chemicals, including 6PPD.  If the draft priority chemicals are included in the final report, due June 1, 2024, and not amended by the Legislature during the 2025 Legislative Session, the chemicals will become priority chemicals upon adjournment.

Other States.  On October 1, 2023, California adopted a regulation listing motor vehicle tires containing 6PPD as a priority product under its safer consumer products law.  By March 29, 2024, manufacturers have the option to submit a chemical or product removal notification, a chemical or product replacement notification, or a preliminary alternatives analysis report.

6PPD.  6PPD is added to the list of priority chemicals in SPWA.

Safer Products for Washington.  For the purposes of SPWA, a motorized vehicle tire containing 6PPD is a priority consumer product.  For such products, Ecology must determine regulatory actions and adopt rules to implement those determinations consistent with the SPWA process but subject to the following timeline:

• by June 1, 2025, Ecology must determine an initial set of regulatory actions; and
• by June 1, 2026, Ecology must adopt rules to implement the initial set of regulatory actions.

Motorized vehicle tire includes, without limitation:

• a tire intended for use on light duty vehicles, motorcycles, motor homes, medium- and heavy-duty trucks, buses, and trailers; and
• tire tread material.

Motorized vehicle tire does not include:

• a tire imported into or sold in Washington as a component of a motorized vehicle; or
• the used components of a retreaded tire.

Ecology may further define "motorized vehicle tire" by rule.