Potassium Bromate: Does Your Bread Contain a Cancer Causing Additive? by Kirby Wetzel, November 03 2015, 1 Comment

With the holidays approaching, thoughts of doughy, warm, flour laden dishes are dancing in my head. Taking center stage in my delicious daydreams are bread, rolls, stuffing, pastries and desserts baked with flour. Absent from my dreams, though, not absent from all baked goods, is potassium bromate. What is potassium bromate you may ask?  Why, it’s an additive that has been linked to cancer. Then why is it in your bread?  Excellent question.

Potassium bromate is a powerful oxidizing agent that chemically ages flour much faster than open air. It bleaches and strengthens the dough, allowing it to rise higher and faster and results in an appealing, albeit unnaturally white color. Decades ago, when potassium bromate was first introduced, the theory was that the finished bread product would be virtually devoid of the additive—it would change to potassium bromide, a harmless byproduct, during the baking process.  However, in the event that too much is used, or the bread does not bake at a high enough temperature for a long enough time, a residual amount will remain. Okay, not enough to cause any damage, nothing to worry about.

And then, in 1982, it was found to cause tumors in rats. The FDA, instead of placing an outright ban on the use of potassium bromate, merely encouraged bakers to give it up voluntarily.  

The United Kingdom (UK) and Canada banned the use of bromates in 1990 and 1994, respectively. In 1991, California declared bromate a carcinogen under the state’s Proposition 65, which requires any baked good sold in California to have a cancer warning if it contains more than a certain level of bromate. The EWG reported that, in 1999 the International Agency for Research on Cancer determined that the additive is a possible human carcinogen. It is not allowed for use or is banned as a food additive in a number of countries, including the UK and Canada (mentioned above), as well as Brazil and the European Union.

Many bread manufacturers have voluntarily removed potassium bromate from their recipes. However, just last month, more than 30 years after it was discovered to cause tumors in laboratory rats, the EWG released a list of 86 products currently on grocery store shelves that contain the ingredient. Notably, a few well-known brands such as Hormel Foods, Weis Keiser, and Goya have products on the list.

It has been found that there is a direct correlation between the amount consumed and the incidence of damage and cancer. So, if you don’t eat too much of it, it should be okay, right? Everything in moderation, right?  Well, that is up to you.  

In laboratory tests, it was found that exposure to potassium bromate increased the incidence of both benign and malignant tumors in the thyroid and peritoneum (the membrane lining the abdominal cavity). Further, it was found that if potassium bromate was ingested, the result was a significant increase in cancer of the thyroid and kidneys, among other organs.

I'm not finished. Potassium bromate also has the potential to mess with and disrupt the genetic material within cells. It can be transformed into molecules called oxides and radicals. These highly reactive little jerks damage DNA and may play a role in the development of cancer. Finally, scientists have observed such damage in human intestine and liver cells, where exposure to the additive resulted in chromosomal damage and breaks in DNA strands. All for faster rising times and more attractive, whiter bread? No thanks!

Remember what I said earlier? The theory is that the finished bread product would be virtually devoid of the additive? That it would morph into potassium bromide, a harmless byproduct, during the baking process? Well, not so fast. Testing in the UK revealed that potassium bromate remains detectable after baking, in unwrapped as well as packaged breads.

Bottom line: Read labels. Avoid food products that contain this chemical.