California to declare COFFEE a cancer risk amid claims it contains toxic chemicals

There have been many reports recently describing the potential cancer-causing (carcinogenic) properties of various foodstuffs. The headline of this article in the Mail certainly gives the impression that coffee is about to be added to this list; indeed, it suggests that California is poised to enshrine the carcinogenic properties of coffee in law. However (and this is a common theme at Research the Headlines), in this case the substance of the headline does not quite match up with the text in the rest of the article.

The main body of the report discusses the possible link between coffee and cancer in a well-balanced manner. Firstly, it identifies acrylamide as the compound of chief concern and states that acrylamide forms in certain foodstuffs when these are cooked at high temperatures. This is true: in a landmark study in 2002, a group led by Margareta Törnqvist at Stockholm University found that heating carbohydrate-rich foods to temperatures above 120 °C (by frying, for example) gave rise to significantly elevated levels of acrylamide in the final cooked products. The amount of acrylamide formed correlated well with the temperature of cooking, with temperatures of over 200 °C producing acrylamide levels of up to 4000 micrograms of acrylamide per kilogram of food (compared to a level of less than 5 micrograms of acrylamide per kilogram of the same food before cooking). The article correctly identifies starchy foods such as potatoes as being those showing the highest levels of acrylamide after high-temperature cooking.

Acrylamide has also been shown to form in coffee when the beans are roasted, and hence the potential for people to ingest acrylamide when they drink coffee made from these beans.

The article then correctly states that there exists considerable debate in the scientific community as to whether or not acrylamide is indeed a carcinogen in humans. Two separate independent sources are noted in this regard: the National Cancer Institute’s website and Dr. Robert Shmerling of Harvard Medical School. Both sources agree that the link between human cancers and acrylamide ingestion is not clear-cut at this time. This stands in contrast to studies in animals, in which a link between ingestion and cancer seems more conclusive. It is primarily on the basis of these animal studies that acrylamide has been flagged as a potential carcinogen in humans, by bodies such as the US Food and Drug Administration, the European Chemical Agency and the World Health Organization.

With this scientific background established in a clear manner, the article then turns to focus on the current legal proceedings taking place in California, under a state law called “Proposition 65”. This law requires businesses to display warning signs on their premises if they sell anything that contains substances deemed harmful by the courts. The actual wordage on these signs seems almost guaranteed to produce mass-hysteria, and would probably make an interesting “Research the Legal Disclaimer” study:

“Warning: Some products sold in this store contain chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.”

Such signs are already displayed in coffee shops (and a host of other public spaces) across California, and there is an argument that their ubiquity diminishes the impact of their message. It is also not clear that the signs give a balanced view of the risks. As the German philosopher-physician Paracelsus said 500 years ago, it is “the dose that makes the poison”. At the current time, it is far from clear as to whether the (often) low concentrations of carcinogens present in these public spaces actually constitute a risk to our health or not.

The crux of the article revolves around whether a judge can (or should) be able to rule on the likelihood that acrylamide (and hence all kinds of foods cooked at high temperatures) is a human carcinogen, when there is no clear scientific consensus on this at the current time. The legal action in California is being brought by the Metzger Law Group, who have previously made successful claims against fast food outlets over essentially the same issue (acrylamide in their French fries). Whatever the outcome, this is unlikely to be the last we hear of acrylamide and its possible link to human cancers.

On the whole, then, this is a well-balanced and essentially correct account of the possible carcinogenic effects of acrylamide in foodstuffs, with a special focus on the legal proceedings currently underway in California regarding coffee. The piece is largely free of inaccuracies and hyperbole, although the title does not quite do the rest of the content justice. Simply changing “California to….” to “California could…” would have summed up the contents of the article much more accurately. The trouble is, there wasn’t room for this because “coffee” had to be written in capitals, to grab our attention…