Valerie George02.22.24
—Is Forewarned Forearmed?
Dear Forewarned:
It might be beneficial to review what Proposition 65 is and how it applies to cosmetics. Proposition 65 is The Safe Drinking Water and Toxic Enforcement Act of 1986 that was voted into California law by citizens of The Golden State. It is designed to protect drinking water and consumers by informing consumers about potential exposure to toxic and cancer-causing chemicals. When purchasing or consuming a product, you’ll notice a sign or inscription that reads, “Warning: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.”
Peruse any grocery store aisle in California and you’ll find warning signs by the bread, from acrylamides found in the crust. Grabbing a latte from Starbucks? A sign perched where you grab your drink will warn you of the dangers of acrylamides and naturally-occurring caffeic acid in the coffee beans. Dare we tell the French their decadent bottles of Bordeaux require the warning at a liquor store due to the alcohol content? You don’t even need to be in California to see the warning—it’s also inscribed on goods such as urinal cakes (1,4-dichlorobenzene), which I first noticed as a youth in Ohio during my first job as a janitor.
You may be wondering why items containing Prop 65 ingredients aren’t just banned. We can do without urinal cakes, in my opinion, but could you imagine banning bread, coffee and wine? Prop 65 isn’t a forbidden chemical list. It’s about disclosure and allowing the consumer to make an informed decision whether to use a product.
I won’t go into how chemicals get added to Prop 65—some are justified, some are seemingly arbitrary. What you need to know as a formulator or brand is that if the good being sold contains a chemical on Prop 65, it might need the Prop 65 warning on the packaging and your e-commerce website.
I say “might” because there are two possible quantitative thresholds to consider in determining whether your good needs the warning:
If the chemical listed on the Prop 65 list does not have a safe harbor limit, any quantity of the chemical present requires the disclosure warning. For example, Cocamide DEA, a nonionic surfactant listed in 2012, has no safe harbor limit. Therefore, any Cocamide DEA content in a product requires the Prop 65 warning.
If the chemical has a safe harbor limit, and the amount of chemical is below the threshold of “no significant risk level,” no disclosure warning is required.
A safe harbor limit is calculated from the likelihood of a chemical causing cancer in 1 out of 100,000 individuals when they are exposed to more than x μg per day, daily, for 70 years. Anything less than this dose is considered safe (hence no significant risk level) and only products exceeding this safe harbor limit would need a warning.
Cocamidopropyl betaine (CAPB), the ingredient in question, is not listed on Prop 65. However, it may contain trace amounts of dichloroacetic acid, an inert impurity resulting from the manufacturing process. Dichloroacetic acid was listed on Prop 65 in 1996 and 2009 for cancer and male developmental toxicity, respectively.
A typical 30% active CAPB contains a maximum 100μg dichloroacetic acid according to the Cosmetic Ingredient Review Panel. If at the maximum level, the neat material would require a Prop 65 warning because it is above the safe harbor limit of daily exposure (think of the workers handling it), which is 17μg per day.
However, a finished cosmetic product wouldn’t necessarily need the warning because the neat raw material would have less dichloroacetic acid and we are diluting it. Let’s say we’re formulating a body wash with 15% CAPB (wt./wt.), and your CAPB contained 100μg dichloroacetic acid. The dichloroacetic acid content would be 15μg per 100g of body wash. A consumer would not use 100g of body wash daily, so the consumer’s daily exposure is much less. Even if you put a whopping 10g of body wash on a loofah, your exposure per shower would be only 1μg. Therefore, using CAPB at this level, with its dichloroacetic acid impurity, is considered safe for consumers and does not violate Proposition 65 or put consumers at risk.
In my opinion, every formulator needs to be concerned about Prop 65. No matter where you sell your products, there is an opportunity for your product to land in California. When formulating, it would be helpful to ask your raw material suppliers for a Prop 65 statement on all raw materials (even on natural materials like peppermint oil!) so you can understand the risk for using each ingredient.
To learn more about what’s on Prop 65, visit https://oehha.ca.gov/proposition-65/proposition-65-list
Valerie George
askvalerie@icloud.com
Valerie George is a cosmetic chemist, science communicator, educator, leader, and avid proponent of transparency in the beauty industry. She works on the latest research in hair color and hair care at her company, Simply Formulas, and is the co-host of The Beauty Brains podcast. You can find her on Instagram at @cosmetic_chemist or showcasing her favorite ingredients to small brands and home formulators at simply-ingredients.com