whole article can be seen at The-Scientist.com

Plastic in My French Fries?Scientists probe acrylamide in food | By Barry A. Palevitz

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Every research scientist knows that discovery often depends as much on happenstance--serendipity--as it does on methodical searching. If a group of researchers from Stockholm didn't know it earlier, they certainly learned the lesson over the last five years. The presence of acrylamide bound to hemoglobin in laboratory workers who perform polyacrylamide gel electrophoresis--a commonly used method to separate and analyze proteins-- wasn't necessarily surprising, but when Emma Bergmark of Stockholm University also found it in people who didn't work with the reagent, it was indeed puzzling.1 So a group led by Margareta Tornqvist, also of Stockholm University, decided to find out how the chemical-- a known neurotoxin and possible human carcinogen--found its way into the bloodstream of John and Jane Andersson.

Preliminary data indicated that acryl-amide levels are much lower in wild animals, so the researchers wondered if people ingest it in food. And, because it is also found in tobacco smoke, they suspected that high- temperature heating might be involved. To find out, they fried rat food and, after feeding it to animals for one to two months, compared the amount of acrylamide in the rats' blood to levels in those fed an unfried diet. Not surprisingly, the amount of acrylamide-hemoglobin adduct was 10 times higher in rats on a fried food regimen when measured by combined gas chromatography and massspectrometry.2 The level was also similar to that detected previously in human controls, further strengthening the hypothesis that there's more than ketchup on french fries.

The group's next step was to actually measure acrylamide in cooked food, and what they found set off alarm bells from Scandinavia to San Francisco. First announced in a press release last April and formally published by the American Chemical Society in August,3 the researchers discovered an average of 0.4 mg/kg of acrylamide in restaurant-prepared fries, and potato chips weighed in at 1.7 mg/kg. Just to be sure, the team used two methods to measure acryl-amide instead of one, and their numbers were reproducible. Oven baking is also a problem; acryl-amide is even in break- fast cereals.

Interestingly, cooked protein-rich foods, such as chicken or fish, contain far less acrylamide, while fried beet roots have more--in other words, it's carbohydrates that count . Acrylamide doesn't accumulate after boiling, so frying and baking are necessary. "I would say that boiling at 100°C is the only safe cooking method," advises Tornqvist. That might not sit well with an increasingly obese public whose appetite for fast food seems insatiable.