Chemicals in Coke and Pepsi: Cancer-Causing or Worth the Taste?

In response to a California law that requires drinks containing certain levels of carcinogens to be labeled, Coca-Cola and PepsiCo have agreed to adjust their drink recipes, rather than add a cancer warning to their products. While some argue that this is another scare tactic of the environmental movement, others may think twice before grabbing a soda.

The 1986 California law in question, Proposition 65, aims to protect California residents from chemicals that may cause cause cancer, birth defects or other reproductive harm. The law requires the governer of California to publish an annual list of such chemicals and that warning labels be included on consumer products that contain those chemicals.

It turns out that the cooking process used to create the caramel coloring in soda products leads to the creation of 4-methylimidazole (4-MEI). At high doses, 4-MEI has been shown to cause seizures in rabbit, mice, and chicks and cancer in rats. As a result, 4-MEI is now on California’s list of probably carcinogens, meaning that companies would need to include warning labels on their products, unless they lower the amount of 4-MEIs found in soda.

As might be expected, the beverage industry is vehemently opposed to having 4-MEI listed as possibly cancer-causing, insisting that the scientific evidence is weak and that there is no health risk. Just the same, rather than put cancer warning labels on their products, Coca-Cola and PepsiCo have decided to change their products to comply with the California regulations.

The U.S Food and Drug Administration claims that an individual would have to drink over a thousand cans of soda a day to reach the levels of 4-MEI necessary to cause cancer.

This may be true, but what this type of statement does not take into account is that individuals are already exposed to many carcinogenic chemicals throughout the day. What happens when you have a couple of 4-MEI-infused cokes per day, wash your hair with shampoo that contains Sodium Laurel Sulfate (possible endocrine disruptors), use fragrances that include phthalates (immune system toxicants that impact the reproductive system), drink out of plastic water bottles that contain Bisphenol A (an endocrine disruptor), and breathe in air that has been toxified by the use of cleaning supplies? This list could go on indefinitely (perfume, deodorant, shower curtain liners, foaming soaps, cosmetics, lotions...). While exposure to any one of these items in isolation may be harmless, what is the effect of low-levels of exposure to multiple harmful substances over time?

The fact right now is that no one really knows what combinations of toxic chemicals may cause cancer or other harmful health effects. It is not considered ethical to expose people to possible carcinogens or combinations of carcinogens to see if they develop cancer. At the same time, it seems like every day a new report comes out identifying another harmful product. Add into the mix that some individuals are more at risk than others due to health conditions or chemical sensitivities, and the potential harm increases.

While the amount of 4-MEI in a few bottles of Coke or Pepsi may alone not cause cancer, combined with the vast array of other carcinogens in our lives, it may indeed cause harm. At the very least, it is yet another data point for those of us trying to navigate the ever increasing array of evidence that harmful chemicals are omnipresent in the air we breathe, in the products we use in our homes, and in what we consume.