California Proposition 65 litigation over acrylamide in food has been heating up lately, receiving national news coverage in anticipation of a ruling in a fiercely contested case involving exposure to acrylamide in coffee.
Acrylamide is generated when certain foods are baked, fried or otherwise heated to high temperatures, causing the food to brown or caramelize. Acrylamide is particularly likely to be formed in high-carbohydrate foods such as French fries, potato and vegetable chips, cookies, crackers, cereals, breads and bagels, but also has been found in grilled meat, some fruits, nuts and – perhaps most notoriously – coffee.
Prop. 65 prohibits businesses from knowingly and intentionally exposing California consumers to a chemical known to the state of California to cause cancer or reproductive harm without first providing a warning. (Cal. Health & Safety Code § 25249.6.) For some listed chemicals, California’s Office of Environmental Health Hazard Assessment (OEHHA) has established safe harbor levels. Exposure below these levels does not require a warning.
Acrylamide was listed under Prop. 65 as a carcinogen in 1990, but it was not until 2002 that a Swedish study discovered its prevalence in a wide variety of cooked foods. Acrylamide was later listed in 2011 as a reproductive toxicant.
The current safe harbor levels are 140 micrograms per day as the “maximum allowable dose level” (MADL) for reproductive toxicity, and 0.2 micrograms per day as the “no significant risk level” (NSRL) for cancer. The NSRL for acrylamide was established shortly after it was listed as a carcinogen, and this was based on animal experiments that used very high doses compared to common human exposure scenarios. Since then, several researchers have suggested a higher NSRL. Interestingly, OEHHA even issued a proposal in 2005 to raise the NSRL for acrylamide, but withdrew that recommendation four years later.
The International Agency for Research on Cancer (IARC) has determined that there is “inadequate evidence in humans for the carcinogenicity of acrylamide,” based on the review of two human cohort studies, published in 1986 and 1989, where inhalation exposure to acrylamide was evaluated in an industrial occupational setting. Nonetheless, IARC classified acrylamide as a probable human carcinogen (group 2A) based on animal studies. Several recent epidemiology studies have not identified a cancer risk associated with typical dietary intake of acrylamide.
The safe harbor level does not specify the chemical concentration in a particular product that triggers the warning requirement. That can be determined through an exposure analysis, or established through consent judgments and settlement agreements.
In 2005, the California attorney general sued a number of fast-food restaurant companies and potato chip manufacturers under Prop. 65, alleging that the companies had failed to provide warnings for exposure to acrylamide in french fries, potato chips and tater tots. The lawsuits resulted in consent judgments requiring a 20 percent to 50 percent reduction in acrylamide levels, to 275 parts per billion (ppb) over three years, and resulted in settlement payments of up to $1.5 million.
Prior to filing a complaint asserting violation of Prop. 65, a private plaintiff must serve a sixty-day notice of violation on the alleged violator and government enforcement agencies providing notice of the alleged exposure. In the past three years alone, more than 268 sixty-day notices have been served. Only about two dozen cases have settled, with acrylamide limits ranging from 10 ppb for white bread, to 75 ppb for cookies and crackers, to 281 ppb for potato chips and 350 ppb for veggie chips and snack foods. The acrylamide limits for potato and veggie chips transpired after the California attorney general’s office objected to an initial proposal with higher limits.
Many defendants have found it difficult to comply with these acrylamide limits and, faced with the prospect of labeling their food products with a warning, have been forced to litigate. Defendants in those cases are expected to raise a variety of defenses, including that: (1) the defendants should not be liable for acrylamide created by consumer toasting of their products, (2) acrylamide exposure does not exceed the safe harbor level when based on the amount and frequency of consumption by an average consumer, and (3) an alternative safe harbor level should apply because the acrylamide is formed during “by cooking necessary to render the food palatable” or safe for consumption, also known as the “cooking provision.” (Cal. Code Regs., tit. 27, § 25703, subd. (b)(1).)
The Coffee Cases
The highest profile acrylamide cases have been filed against Starbucks and nearly 100 other coffee manufacturer and retailer defendants. After eight years of litigation, a ruling is expected within days to months.
Two lawsuits were filed in 2010 by the Council for Education and Research on Toxics, the same private enforcement group that filed the first Prop. 65 lawsuits alleging acrylamide in French fries and potato chips. So far, 13 defendants, including BP West Coast Products, Yum Yum Donuts, and 7-Eleven, have settled, agreed to post warnings and paid up to $675,000. A recent mediation with retailer defendants failed to yield any additional settlements.
Defendants argue there is no increased risk of any chronic diseases, including cancer, associated with coffee consumption. In fact, defendants contend there is strong evidence that drinking coffee is associated with a decreased risk of several major chronic diseases, such as cardiovascular disease, Type 2 diabetes, liver disease, liver cancer and endometrial cancer.
The case has been tried in phases. In the first phase, defendants challenged whether exposure to acrylamide in coffee exceeds the NSRL, and argued that such exposure does not cause an increased risk of cancer because other chemicals in coffee counteract any carcinogenic effects. The court held that defendants failed to meet their burden on the first point and declined to consider the second point.
Defendants also argued that under the First Amendment, they could not be required to post a warning that they felt was inaccurate, but the court held the warning requirement is reasonably related to an underlying state interest. Interestingly, this same argument was recently successful in getting a preliminary injunction against enforcement of the warning requirement for glyphosphate against the parties in National Ass’n of Wheat Growers v. Zeise, Civ. No, 2:17-2401 WBS EFB. In that case, Monsanto and various growers convinced the court that the compelled warning – requiring them to state that glyphosphate is known to the state of California to cause cancer – was commercial speech and was likely to violate the parties’ First Amendment rights because, among other things, the warning was “misleading at best” in light of the fact that glyphosate was listed based on IARC’s determination that it was a “probable” carcinogen. The same argument might provide a good avenue for appeal, if the defendants in the coffee case are unsuccessful at the trial level.
The second phase of the trial concerned whether exposure to acrylamide in coffee is below an “alternative significant risk level” (ASRL) – on the grounds that acrylamide created through the roasting of coffee beans is necessary to create a product that is palatable and safe for consumption. This second phase of the trial concluded in late 2017 and a ruling is expected in a matter of days to months.
If the court’s ruling does not completely dispose of defendants’ potential liability, the case will move to a third phase to determine damages against each individual defendant. Prop. 65 carries civil penalties of up to $2,500 per exposure.
Although the NSRL for acrylamide in coffee remains unsettled and is likely to be challenged as to other foods later this year, food manufacturers who want to evaluate their legal exposure can have their products tested to see if they produce doses to consumers above the current or anticipated safe harbor level. With that information, they can decide whether to attempt to reduce the concentrations in the beverage or sell with a warning in California.
The Next Target?
Enforcement groups may focus next on furfuryl alcohol, which is also formed by thermal processing. This chemical was listed as a carcinogen under Prop. 65 in September, 2016. It may be present in many of the same products as acrylamide, but also has been found in wine, beer, and spirits, ice cream, juice beverages, rice cakes, and pasteurized milk.
Unlike acrylamide, there is no safe harbor level for furfuryl alcohol, so any amount may require a warning. As of the date of this article, there have only been six 60-day notices issued for this chemical since the warning requirement took effect. The notices have already targeted the major potato chip manufacturers, and it is likely that further enforcement actions will be brought. As with acrylamide, food manufacturers may want to test their products for furfuryl alcohol, and if it is identified, consider whether to seek to reformulate or sell with a warning in California.
 The MADL is the highest level at which the chemical would have no observable adverse reproductive effect assuming exposure at 1,000 times that level.
 The NSRL is the daily exposure level likely to result in no more than one excess case of cancer in an exposed population of 100,000 assuming lifetime exposure at that level. This can be explained as the exposure likely to increase your risk of cancer by .00001 percent, or 10-5.
 Defendants argued this ASRL should be 10-4, which can be explained as the daily exposure level likely to result in one excess case of cancer in an exposed population of 10,000 assuming lifetime exposure at that level, or likely to increase your risk of cancer by .0001 percent.
Rachel Novick and Becca Brewster are scientists at Cardno ChemRisk, and were contributing scientific advisors for this article.