What a Headache: California Regulators Want To Label Acetaminophen a Carcinogen

The science is unsettled, and a new warning label would probably just confuse people.


California regulators want to classify acetaminophen, a common over-the-counter drug, as a carcinogen—proving that not even headache relievers are safe from government overzealousness.

The issue stems from Proposition 65, a state law requiring the Office of Environmental Health Hazard Assessment(OEHHA) to publish a list of chemicals known to cause cancer or reproductive harm. Manufacturers whose products include these chemicals must provide clear labels warning consumers of the potential harm. Prop 65's reach is so vast that California's list of carcinogens encompasses over 900 chemicals, prompting criticism that law imposes costly regulatory burdens and does more to confuse customers than warn them.

"We're now dealing with the statute that is being inappropriately applied to baby food, to infant formula, to coffee," said Karyn Schmidt, senior director of regulatory and technical affairs at the American Chemistry Council. In 2018, Schmidt argued that using ingredient disclosure as a safety measure inefficiently manages the risk of cancer.

Placing a warning label on the drug "could prevent consumers from treating their aches and pains," or it could lead them to try "something stronger and unnecessary," state Assemblyman Jim Wood (D-Healdsburg) told the Daily Democrat.

Oncologists have not reached a consensus about the correlation between acetaminophen and cancer risk. Cancer Prevention Research, a peer-reviewed medical journal published by the American Association for Cancer Research, found in 2011 no association between acetaminophen use and the risk of developing pancreatic cancer. Annals of Oncology last year reported no correlation between regular acetaminophen use and endometrial cancer risk in its studies.

State regulators have reviewed a total of 133 studies of the drug, which yield little consensus. These studies have limitations preventing them from drawing conclusive evidence that acetaminophen directly causes cancer. It's not feasible to identify most acetaminophen users based on drug prescription data, for instance. Any evidence of pain associated with acetaminophen use is also dubious, as similar symptoms are associated with other analgesics.

Not only does the abundance of labels make consumers uncertain about which products actually cause cancer, but businesses face severe repercussions if their labels don't comply with state regulations. Companies that fail to properly adhere to the regulation face hefty penalties and opportunistic litigation. Amazon has faced over 1,000 Prop 65 notices as of last August, with retailers such as Target, Walmart, and CVS also facing litigation.

The government shouldn't force a pain-reliever to identify as a carcinogen, especially when the science is far from settled and the most likely result would be unnecessary confusion and fines.

NEXT: Trump Campaigned on Saving Factory Jobs, but U.S. Manufacturing Just Went Through a Year-Long Recession 

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  1. According to California’s proposition 65, reading these articles is “known to the state of California to cause cancer”.
    I quit reading any of that stuff decades ago.

    1. I think the state of California itself causes cancer, which is why any product they study in CA is invariably found to cause cancer

      1. Certainly CA causes a cancer and deterioration of reason, logic and sanity.

    2. I picked up some tools for tile laying yesterday. The *trowel* had a prop 65 warning on it.

      1. The handle was made from plastic. Everyone knows plastic causes cancer.

  2. Nearly ALL foods contain certain levels of one of more of the following: arsenic, cadmium, lead, and mercury.
    Ironically, the amounts established by Proposition 65 are less than that what occurs naturally in numerous fruits, vegetables and water. The Proposition 65 standards are so tough that the following natural products are in violation of Proposition 65:

    Yams, turnips, apples, artichokes, carrots, cucumbers, green beans, lettuce, spinach, potatoes, corn and many more fruits and vegetables. For instance, carrots contain as much as 12.80 micrograms of arsenic in a one cup serving; green beans contain as much as 28.75 micrograms of lead in a one cup serving, 56 times the allowable limit.

  3. Is this an example of our betters winning the culture war the Rev is always talking about?

    1. My diagnosis for the Reverend is to take 5K mg of acetominophen daily for six months, since he is such a pain in the ass.

  4. … and the most likely result would be unnecessary confusion and fines.

    This is California. Those fines are very necessary.

    1. This is California. Those fines are very necessary.

      California is not.

    2. I came here to say the same thing. Since when are fines a bad thing?

      I am stuck here for another few months, I just ordered a new computer monitor online. I had to pay a $5 recycling fee in order to even purchase it!

      Was doing my taxes, California asks: “Did you make any untaxed out-of-state purchases in 2019?”

      I can’t wait to go back to a no state income tax state. Just a few more months……

  5. Companies that fail to properly adhere to the regulation face hefty penalties and opportunistic litigation.

    Not only that, they risk cancer or reproductive harm!

  6. The science is unsettled, and a new warning label would probably just confuse people.

    Headache now or cancer in 30 years? I don’t think it will confuse people.

  7. The science is unsettled

    Hey Masha, science is always unsettled. You don’t ‘settle’ science. That’s what gets environmentalists into so much trouble.

  8. So, the plain tylenol will have to have a Prop. 65 label and the tylenol laced with cyanide won’t, right?

  9. Proposition 65 warnings don’t confused anybody but tourists. All the residents ignore them, or laugh at them.

  10. It’s Tylenol. The drug wouldn’t be over the counter or, hell, even approved by the FDA if it had to go through new drug development today. Prop. 65 is a joke, and needs to be repealed, but I don’t agree with the tone of the article that Tylenol is so innocuous that a warning label is inherently ridiculous.

  11. The best thing for the rest of us, and maybe for some Californians, is for that state to go full bat shit nanny socialist totalitarian before the end of the decade. The resulting collapse, famines, and riots just might be enough to get normal (and even left-normal) people to wake up and stop pandering to progressives.

  12. I think prop 65 is great – there’s no chance of anyone being surprised when they get cancer. They’ve made it abundantly clear that cancer has invaded everything sold on amazon, and most things sold in stores. People in California are well aware that no amount of off-the-grid living would even put a dent in the legions of cancer cells already infesting their lives.

    Plus that means fewer lawsuits. Cancer is here to stay.

  13. Prop. 65 has been amended, and last year there took effect refinements to it. There’s now a list of substances and their quantity limits below which no warning is required. Not only that, but the labels now must state specifically which substances are being warned of. So it’s more informative and realistic than it used to be.

    1. Prop 65 should be repealed. Its a waste of money and the information it provides likely causes more psychological harm in the form of unnecessary anxiety and worry than any benefits it has provided anyone by letting them know that the chair they sit on at work contains chemicals known to the state of California to cause cancer [not mentioned: at levels 1000 times beyond what is found in the chair and only when consumed through the nose with a straw. ] The only people who want it are the people who financially benefit from it — regulators, politicians, lawyers, and career activists. The amendments will not save it from being crappy legislation. What, did you work on it yourself?

  14. Warning:. It is known to the state of California, that being a human results in death.

  15. The government shouldn’t force a pain-reliever to identify as a carcinogen, especially when the science is far from settled and the most likely result would be unnecessary confusion and fines.

    The government should follow government rules for drugs, which is that this should be included under “possible side effects” if it meets the criteria.

    As far as I can tell, a Prop 65 warning was never intended to warn people about products that cause cancer; its stated purpose was to protect drinking water from deliberate release by businesses and accidental exposure at a place of business. Neither of those applies to OTC pain killers.

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