U.S. food additives banned in Europe: Expert says what Americans eat is "almost certainly" making them sick

London — From baguettes to focaccia, Europe is famous for its bread. But there's one ingredient conspicuously missing: Potassium bromate. It's a suspected carcinogen that's banned for human consumption in Europe, China and India, but not in the United States.

In the U.S., the chemical compound is used by some food makers, usually in the form of fine crystals or powder, to strengthen dough. It is estimated to be present in more than 100 products.

"There is evidence that it may be toxic to human consumers, that it may even either initiate or promote the development of tumors," professor Erik Millstone, an expert on food additives at England's University of Sussex, told CBS News. He said European regulators take a much more cautious approach to food safety than their U.S. counterparts.

Asked if it can be said with certainty that differences in regulations mean people in the U.S. have developed cancers that they would not have developed if they'd been eating exclusively in Europe, Millstone said that was "almost certainly the conclusion that we could reach."

It's not just potassium bromate. A range of other chemicals and substances banned in Europe over health concerns are also permitted in the U.S., including Titanium dioxide (also known as E171); Brominated vegetable oil (BVO) (E443); Potassium bromate (E924); Azodicarbonamide (E927a) and Propylparaben (E217).

Millstone, who's spent almost half a century researching food and agriculture science, said most Americans were likely completely unaware that they were being exposed on a daily basis to substances in their food viewed as dangerous in Europe.

"They probably just think, 'Well, if it's available or it's in the store, it's probably fine,'" he said.

In a statement to CBS News, the U.S. Food and Drug Administration (FDA) said all food additives require "pre-market evaluation" and "regulations require evidence that each substance is safe at its intended level of use before it may be added to foods."

"Post-approval, our scientists continue to review relevant new information to determine whether there are safety questions and whether the use of such substance is no longer safe," the agency added.

Stacy McNamara is from upstate New York, but she has lived in London for a decade. She said raising children in the U.K. had opened her eyes to what's allowed in foods in the U.S.

McNamara has no plans to ever move back home, and she told CBS News that food safety was "for sure" a part of that decision.

In a statement to CBS News, the FDA said that when used properly, potassium bromate converts into a harmless substance during food production.

The FDA acknowledged, however, that not all of the compound used in any given recipe may convert during the production process, but that control measures were utilized to minimize the amount in final products.