Acrylamide was a pretty much unknown chemical in foods until 2002. One of my friends from Sweden, Sune Eriksson, played a key role in discovering it [1]. Back then, it was already described as carcinogen. Acrylamide is known to develop under high temperatures in the presence of certain amino acids and starch/sugar. The products best-known to contain acrylamide are coffee, French fries, soft and crispy breads and biscuits.
There is an unfortunate relationship between the flavor and the acrylamide level though: the higher the browning level, the more flavor a product tends to get, and the higher the acrylamide level of the product will be.
In 2015, the European Food Safety Authority (EFSA) issued an opinion stating the lethal doses (LD50) in rats, mice, rabbits and guinea pigs are between 107 and 180 mg/kg body weight [2]. With regards to the carcinogenic effects of acrylamide, the EFSA report states:
“For most cancers there is no consistent indication for an association between acrylamide exposure and increased risk. A few studies suggested an increased risk for renal cell, and endometrial (in particular in never-smokers) and ovarian cancer, but the evidence is limited and inconsistent”.
In 2016 in California, the Council for Education and Research on Toxics (CERT) started a lawsuit against 90 coffee roasters and retailers, including Starbucks, Costco, Trader Joe’s and 7-Eleven. CERT alleged the coffee poses a risk of causing cancer in consumers, caused by the acrylamide generated during their roasting process. An outcome in favor of CERT would have meant that the coffee you buy would have to carry a label – in accordance with proposition 65 – warning you of cancer. This would have been similar to what can now be seen on many cigarette packs in Europe. The first case that went to court was lost by the coffee industry on April 20, 2016. The court ruled that insufficient evidence was provided by the coffee roasters and retailers that the acrylamide in coffee did not pose a significant cancer risk.
After countless studies and a few trials, there is a new development in August 2020: the Superior Court Judge ruled that coffee producers had provided sufficient evidence that acrylamide, produced during the roasting of coffee, does not cause cancer.
It can be questioned, especially when considering the exposure levels, if providing a cancer warning on labels would have been helpful for consumers – or if it had rather caused confusion. And imagine that not only your coffee is labelled to cause cancer, but every French fries or biscuit you eat. In order to avoid such confusions, the California Office of Environmental Health Hazard Assessment (OEHHA) is proposing regulations [3] that clarify what constitutes a proposition 65 exposure.
So for now, you can have your coffee and drink it – without a cancer warning.
[1] J. Agric. Food Chem. 2002, 50, 4998-5006
[2] EFSA Journal 2015;13(6):4104
[3] https://oehha.ca.gov/proposition-65/crnr/notice-proposed-rulemaking-adoption-section-25505-exposures-listed-chemicals
