Proposition 65
The Proposition 65 list names a particle form of titanium dioxide, for cancer
Direct answer. California’s Proposition 65 list includes “Titanium dioxide (airborne, unbound particles of respirable size)” for cancer, listed September 2, 2011. Those three fields are copied from the Proposition 65 list PDF that prints the date July 31, 2026 on its first page. The listed name is limited to that particle form. OEHHA’s chemical page for the same name says the cancer status is currently listed, the date of listing is 09/02/2011, and the listing mechanism is the Labor Code. The page text checked for this guide does not add a sentence about when exposure occurs. This page does not say that any product category does or does not need a warning. It is not legal advice.
Prop 65 Warning Manager (Shopify App Store · Write a review): “Display California Prop 65 warnings on product pages and keep an audit trail of warning edits, assignments, and storefront activation events.”
Related: CLPLens — Hazard pictograms on the product page, not only the parcel.
Free check first: Prop 65 warning question check runs in your browser and sends nothing.
Checklist before you use the listed name
- Read the current OEHHA list PDF. The copy used here is the file dated July 31, 2026 on page 1.
- Copy the chemical name as printed: “Titanium dioxide (airborne, unbound particles of respirable size)”. Type of toxicity: cancer. Date listed: September 2, 2011. The CAS column for that row is “---”.
- Do not widen the name to titanium dioxide in general. The parentheses are part of the listed name.
- Safe-harbor content is 27 CCR § 25603, quoted below from OEHHA’s final regulatory text. Internet and catalog methods are on the linked guides, not repeated here.
- The list row and the chemical page do not name a product category. Cosmetics are not named there. This page does not decide whether a product needs a warning.
The list row, as printed
Page 1 of the PDF is titled “PROPOSITION 65 LIST OF CARCINOGENS OR REPRODUCTIVE TOXICANTS” and dated “July 31, 2026”. The same page says the list is published in Title 27, California Code of Regulations, section 27001, and that the date refers to the initial appearance of the chemical on the list.
| Column | Text on the list |
|---|---|
| Chemical | Titanium dioxide (airborne, unbound particles of respirable size) |
| Type of toxicity | cancer |
| CAS No. | --- |
| Date listed | September 2, 2011 |
The chemical page uses the same name. Under chemical status it says cancer is currently listed. Under cancer it says listed as causing cancer, date of listing 09/02/2011, and listing mechanism Labor Code. That page does not, in the text read for this guide, describe powders as against a chemical bound in a matrix, or otherwise say when exposure occurs. This page therefore does not characterise exposure. It also does not quote any safe-harbor level figure from that page.
Safe-harbor content in § 25603(a) and (b)
The wording below is from OEHHA’s final regulatory text for Title 27, sections 25601, 25602, 25603, and 25607.2. The PDF states that amendments are shown in underline and strikethrough. The sentences quoted here are the operative wording printed for § 25603(a) and the short-form elements in § 25603(b). Confirm the codified California Code of Regulations before you treat a line as current.
§ 25603(a) opens: “Unless otherwise specified in Section 25607.1 et seq., a warning meets the requirements of this subarticle if it is provided using one or more of the methods required in Section 25602 and includes all the following elements:”
- § 25603(a)(1): “A symbol consisting of a black exclamation point in a yellow equilateral triangle with a bold black outline. Where the sign, label or shelf tag for the product is not printed using the color yellow, the symbol may be printed in black and white. The symbol shall be placed to the left of the text of the warning, in a size no smaller than the height of the word ‘WARNING’.”
- § 25603(a)(2) lead: “The word ‘WARNING:’ or the words ‘CA WARNING:’ or ‘CALIFORNIA WARNING:’ in all capital letters and bold print, and:”
- § 25603(a)(2)(A), for exposures to listed carcinogens: “This product can expose you to chemicals including [name of one or more chemicals], which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.”
The same subsection continues with reproductive, combined, and single-chemical variants in (a)(2)(B) through (E). This page does not repeat them. The list’s type of toxicity for this chemical name is cancer, which is why (a)(2)(A) is the carcinogen sentence quoted above. That is a description of the regulation’s structure, not a statement that a given product needs a warning.
§ 25603(b) opens: “A short-form warning may be provided on the label pursuant to Section 25602(a)(4) if it includes:”
- “(1) The symbol required in subsection (a)(1);”
- “(2) The word ‘WARNING:’ or the words ‘CA WARNING:’ or ‘CALIFORNIA WARNING:’ in all capital letters, in bold print; and”
- “(3) One of the following:” and, for exposures to listed carcinogens, either “Cancer risk from exposure to [name of chemical]. See www.P65Warnings.ca.gov.” or “Can expose you to [name of chemical], a carcinogen. See www.P65Warnings.ca.gov.”
§ 25603(b)(3) continues with reproductive and combined wordings. Those lines, the type-size method, and internet or catalog transmission are on the short-form warning guide, warning examples, and the product-page warning guide.
What this page is not
- Not legal advice, and not a statement that any product, including a cosmetic, does or does not need a warning.
- Not an exposure, health, or dose assessment. No safe-harbor level figure is quoted here.
- Not the internet or catalog method. Those pages are linked above.
- Not a PFAS, lead, or DEHP listing. Those pages are PFAS, lead, and DEHP.
Related pages
- Prop 65 warning question check
- Prop 65 warning examples
- Prop 65 short-form warning
- Product-page warning
- Prop 65 and PFAS
- Prop 65 lead warning
- Prop 65 DEHP warning
- Proposition 65 list (PDF) — dated July 31, 2026
- OEHHA chemical page
- OEHHA final regulatory text (PDF)
- Prop 65 Warning Manager — live App Store listing
- Shopify apps hub
- Tools
Not legal advice. Confirm the current OEHHA list and the codified text of 27 CCR §§ 25602 and 25603 before you treat a chemical name or a warning line as in or out of the safe harbor. The app displays warnings you enter and keeps an audit trail. It does not decide whether a warning is required.