On June 18, 2026, the California Department of Toxic Substances Control (DTSC) issued a final rule adding microplastics to the Candidate Chemicals List (CCL) under the Safer Consumer Products (SCP) program. The rule takes effect on October 1, 2026. As discussed in our prior alert, this listing is potentially relevant to all businesses operating in the State of California that manufacture or distribute products containing plastic.

While the rule imposes no immediate requirements on businesses, it enables DTSC to begin listing microplastic-containing- and generating-priority-products (product-chemical combinations that DTSC determines cause harm) through rulemaking. The listing of a priority product then triggers new regulatory requirements, including notification and an alternatives analysis.

DTSC’s Final Rule Remains Unchanged

DTSC declined to narrow its “microplastics” definition from “plastics that are less than 5 millimeters (mm) in their longest dimension, inclusive of those materials that are intentionally manufactured at those dimensions or are generated by the fragmentation of larger plastics.” Commenters suggested lowering the size limit below 5 mm and including exemptions for products that contain biodegradable plastics, water-soluble plastics, and products that generate secondary microplastics. But the rule’s accompanying Final Statement of Reasons rejected the notion that any “lower size limit” mitigates the hazard traits microplastics exhibit—particle size and fiber dimension, persistence, and environmental mobility—and emphasized their potential negative impacts on human and environmental health. The Statement further suggests that DTSC is reserving a broad definition, preserving “the ability to consider” a wide variety of products, with the intent of narrowing the regulatory scope later via priority products listing. DTSC stated that the broad definition “is appropriate for the stage we are at in our regulatory process.”

SCP Regulatory Framework

Listing a chemical on the CCL could result in the following steps:

1. DTSC identifies and lists priority products that contain one or more candidate chemicals via rulemaking, identifying any candidate chemical the product contains as a chemical of concern.

2. Responsible entities must notify DTSC if they produce, assemble, import, or sell a priority product; conduct an alternatives analysis (which requires evaluation and comparison of a priority product and one or more alternatives to determine whether a safer, feasible alternative exists); and submit an alternatives analysis report to DTSC.

3. Based on the results of the alternatives analysis for the priority product, DTSC can impose a range of regulatory responses to address the hazard or potential exposure, including:

• Requiring additional product information for consumers;
• Imposing use restrictions on chemicals and products;
• Prohibiting the sale of a product or requiring engineering controls;
• Requiring end-of-life management; or
• Ordering funding for green chemistry research.

Potential Priority Products

DTSC’s broad “microplastics” definition, encompassing materials that are both manufactured to be, and that degrade to, less than 5 mm, authorizes DTSC to consider a wide array of products. DTSC first indicated potential priority products in its 2024-2026 Priority Product Work Plan, which gives special consideration to “[r]educing the release of microplastics to the environment during all stages of the consumer product life cycle, including manufacturing, transportation, use, and end-of-life.”

In November 2025, the Department published its preliminary research findings, or Background Document on DTSC’s Microplastics in Consumer Products Research, which evaluates a wide range of product categories. The Department narrowed that range to seven product categories, considering available data, expert input, and feasibility. Among other categories, DTSC specified paint, laundry/dish detergents, and food contact articles as potential targets. The Department indicated that it might “revisit other product categories in the future.” DTSC undertook this multi-stage research process concurrent with its proposal and final addition of microplastics to the CCL.

In general, in order for a product to be listed as a priority product, DTSC must conclude:

• The product potentially exposes the public and/or aquatic, avian, or terrestrial animal or plant organisms to the candidate chemical; and
• Exposure has the potential to contribute to or cause significant or widespread adverse impacts.

When evaluating those prioritization principles, DTSC examines an extensive list of regulatory factors.

Timeline

DTSC’s timeline for identifying and evaluating potential priority products typically ranges from 1 to 3 years. After identifying a potential priority product, DTSC first prepares a product-chemical profile and releases a draft for a pre-regulatory public comment period and workshop. After considering public comments, DTSC then conducts an external scientific peer review, finalizes the profile, and decides whether to proceed with formal rulemaking. The formal rulemaking process then follows California’s Administrative Procedure Act, which must be completed within one year of a Notice of Proposed Action to list a priority product and includes an additional 45-day public notice-and-comment period.

Next Steps

Businesses that manufacture or distribute products that contain plastic should:

• Survey products they manufacture or distribute to determine whether they fall into DTSC’s target product categories;
• Understand the additional regulatory burdens the Safer Consumer Products program imposes;
• Prepare to submit comment(s) on proposed priority products; and
• Look out for mention of microplastics in DTSC’s 2027-2029 Priority Product Work Plan, draft expected Fall 2026.

With an office in San Francisco, Beveridge & Diamond advises clients on environmental regulatory matters in California and across the country. Our Chemicals Regulation and Chemicals industry groups provide strategic, business-focused guidance to the global chemicals industry. In addition, our Consumer Products industry group supports U.S. and multinational companies involved in the manufacture, distribution, transportation, or sale of consumer goods in a competitive and rapidly evolving market. We help clients navigate complex regulatory requirements throughout the product lifecycle. For more information, please contact the authors.