California Proposition 65 Cleaning Chemical Labeling Reference

Why this matters

California Proposition 65 (the Safe Drinking Water and Toxic Enforcement Act of 1986, Health and Safety Code section 25249.5 et seq.) requires any business with 10 or more employees to provide a "clear and reasonable" warning before knowingly and intentionally exposing any person to a listed chemical. The list, maintained by the California Office of Environmental Health Hazard Assessment (OEHHA), passed 900 chemicals years ago and grows every quarter. Cleaning chemistry is heavily represented: ethylene glycol monobutyl ether (butyl), formaldehyde donors, naphthalene, methylene chloride, and several quaternary disinfectant carriers all appear. The plaintiff bar enforces Prop 65 through private 60-day notices of violation; the statutory penalty cap is up to 2,500 dollars per violation per day under Health and Safety Code section 25249.7(b). A cleaning contractor that delivers a labeled drum to a California customer without an appropriate warning is exposed even if the customer is the entity using the product. This article is the working reference for warning content, sign placement, and the safe-harbor methods that an OEHHA-defending attorney will not contest.

Who Prop 65 applies to

The statute applies to:

• Any business with 10 or more employees in the United States (not just California). The employee count is the global headcount of the business, not the count on the California job site.
• The business must "knowingly and intentionally" expose any person in California to a listed chemical. Knowledge is imputed once the chemical is on the OEHHA list; a "we did not know" defense fails as a matter of law.
• Both the product manufacturer and the downstream user share liability. The cleaning contractor that applies a Prop 65-listed product on a California job site can be named in a 60-day notice independent of the manufacturer.

Businesses with fewer than 10 employees are exempt, but the safe-harbor warning text on most professional-channel cleaning chemistry already meets the spec, so practical compliance is not different.

The warning content (Title 27 California Code of Regulations section 25600 et seq.)

OEHHA's 2018 rewrite of the safe-harbor warning regulations set a specific format. Use this format and the safe harbor protects you. Use a paraphrase and you are arguing the case on its merits, which costs money even when you win.

Standard short-form warning for consumer products:

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Standard long-form warning for consumer products:

WARNING: This product can expose you to chemicals including [name of one or more listed chemicals], which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

The warning must include:

• The yellow-triangle exclamation-point symbol, at least as tall as the word "WARNING" in bold all-caps.
• The word "WARNING" in bold all-caps.
• The specific endpoint (cancer, reproductive harm, or both) - the regulator updated this in 2018; "cancer and reproductive harm" without a more specific endpoint is no longer safe-harbor for products that expose to only one type.
• The OEHHA website URL.
• For the long-form warning, the name of at least one listed chemical for each endpoint.

The warning text must appear in English; a Spanish-language warning is also required when the product label is in Spanish.

Sign placement on a commercial job site

For occupational exposures the warning is delivered through the OSHA Hazard Communication Standard (29 CFR 1910.1200) chemical labels and Safety Data Sheets. OEHHA accepts HAZCOM-compliant warnings as a Prop 65 safe harbor under 27 CCR section 25606 for occupational exposures, provided the SDS lists the Prop 65 chemicals and the label carries the required hazard statements.

For environmental exposure to third parties (a building occupant, not a cleaning worker) the warning is the responsibility of the building owner or facility operator. The cleaning contractor's exposure here is generally indirect, but a contractor that places a fogging or pressure-spray application during occupied hours and triggers third-party exposure can be named.

Public-facing warning signs at the point of exposure must be:

• Placed within 4 feet of the warning trigger (the chemical use or storage area) per the OEHHA safe-harbor guidance.
• Large enough that a person near the trigger can read the warning. Six-point type on a 6-foot-tall door is not "clear and reasonable."
• Posted before the exposure begins. A sign posted after the exposure does not satisfy the statute.

The listed cleaning chemicals you actually encounter

The OEHHA list is updated quarterly. The chemicals that appear in commercial cleaning chemistry as of recent listings include:

• Ethylene glycol monobutyl ether (2-butoxyethanol). Common in degreasers, glass cleaners, and general-purpose cleaners. Reproductive-harm listing.
• Formaldehyde. Found as a contaminant in some quaternary ammonium products and as a preservative in some industrial cleaners. Cancer listing.
• Methylene chloride (dichloromethane). Stripping agents, some paint-stripper-adjacent cleaners. Cancer listing.
• Naphthalene. Solvent in some heavy-duty degreasers. Cancer listing.
• Tetrachloroethylene (perchloroethylene). Some specialty solvents. Cancer and reproductive listings.
• Lead. Trace contaminant in some imported cleaning chemistry. Reproductive listing.
• Diisocyanates (MDI, TDI). Used in some floor-coating systems. Reproductive listing.

The supplier's SDS lists Prop 65 chemicals in Section 15 (Regulatory Information). A product that lists no Prop 65 chemicals in Section 15 carries an implicit representation from the supplier that no listed chemical is intentionally present.

The 60-day notice and what to do

A Prop 65 enforcement action begins with a 60-day Notice of Violation served by the plaintiff (often a private attorney) on the alleged violator and on the California Attorney General. The notice must:

• Identify the chemical and the product.
• Identify the alleged exposure route.
• Be served at least 60 days before the lawsuit is filed.

In the 60-day window the alleged violator can:

References

• California Office of Environmental Health Hazard Assessment (OEHHA). Proposition 65: List of Chemicals Known to the State to Cause Cancer or Reproductive Toxicity. Updated quarterly.
• 27 California Code of Regulations sections 25600 - 25607.31. Clear and Reasonable Warnings regulations.
• California Health and Safety Code sections 25249.5 - 25249.14. Safe Drinking Water and Toxic Enforcement Act of 1986.
• California Attorney General. Annual Summary of Proposition 65 Settlements, current edition.
• US OSHA. 29 CFR 1910.1200 - Hazard Communication Standard.
• OEHHA. Article 6: Clear and Reasonable Warnings - safe-harbor guidance.