Study uncovers 50 other acrylamide-like, cancer causing chemicals, home cooking recommended
November 29, 2007
Acrylamide and 50 other heat-induced compounds in foods may cause cancer, scientists have concluded in a report released yesterday of a major three-year EU study into the chemical.
The study adds to the accumulating evidence that acrylamide, formed in foods during heating or frying processes, poses a health problem, and puts more pressure on processors to reduce the chemical in their products.
Reduction may involve reformulation, revising processing and cooking times, or the use of varieties of ingredients that do not result in as much acrylamide formation as their counterparts.
The EU three-year project, known as Heat-generated Food Toxicants (Heatox), was launched to fill in the gaps on the formation of acrylamide in cooked foods and provide advice to industry.
The team found toxicological evidence suggesting that acrylamide in food may cause cancer, Hetox reported.
“Their findings also suggest that there are ways to decrease exposure to acrylamide, but not to eliminate it,” the report stated. “Laboratory experiments succeeded in reducing acrylamide levels in bread and potatoes by adjusting the oil to potato ratio in semi-industrial fryers or minimising long yeast fermentation.” They calculated that successful application of all presently known methods would reduce the acrylamide intake by 40 per cent at the very most.
The Heatox project also found that acrylamide is not the only genotoxic compound that forms when food is heated. The scientific team has created a database of about 800 heat-induced compounds, of which they say 52 are potential carcinogens based on their chemical structure. “Other compounds formed during cooking of food, for example HMF, Furan, and a variety of Maillard reactants and lipid oxidation products may also constitute an increased cancer risk for consumers,” they stated. Future research should focus on these compounds, the researchers advised in the report.
Acrylamide appears to form during processing as a result of a reaction between specific amino acids, including asparagine, and sugars found in foods reaching high temperatures during cooking processes. The process is known as the Maillard reaction. This occurs at temperatures above 100°C (212°F).
Acrylamide hit the headlines in 2002 when scientists at the Swedish Food Administration first reported unexpectedly high levels of the potential carcinogen in carbohydrate-rich foods cooked at high temperatures.
Until then acrylamide was known only as a highly reactive industrial chemical, present also at low levels for example in tobacco smoke.
Since the Swedish discovery a global effort has been underway to amass data about this chemical. More than 200 research projects have been initiated around the world, and their findings co-ordinated by national governments, the EU and the United Nations.
The EU three-year project began in November 2003, bringing together 24 research teams from 14 countries. Most project partners are universities or research institutes, but national authorities and a European consumer organisation are also involved.
In addition to the major findings on acrylamide, the Heatox scientists also found that the presence of acrylamide in home-cooked food is minimal in comparison with industrially or restaurant-prepared foods.
The team concludes that advising citizens on the risks must be a national responsibility as cooking and eating habits vary considerably between countries.
“General guidelines would advise avoiding overcooking when baking, frying or toasting carbohydrate-rich foods,” they stated. “Further acrylamide intake can also be achieved by following a diet without excessive fat or calorie intake.”
The Heatox project has also produced intake calculations, chemical reaction models, exposure assessments, in vivo and in vitro toxicity testing, mitigation proposals to reduce intake, analytical methods for biomarkers and levels and a risk characterisation, of the chemical.
The data was used to produce a six-page acrylamide reduction guide for food processors, one that complements those already produced by EU industry for various food sectors. The Hetox guide focuses on potato, cereal products, and coffee.
In 2005, the European Food Safety Authority (EFSA) endorsed a the risk assessment on acrylamide in food, which was carried out by the Food and Agriculture Organisation and the World Health Organisation.
In that assessment the UN organisations concluded that the margins of exposure for average and high consumption consumers were low for a compound that is genotoxic and carcinogenic and that this factor may indicate a human health concern.
“Therefore, appropriate efforts to reduce acrylamide concentrations in foodstuffs should continue,” the Commission stated.
Earlier this month scientists who conducted a study of about 62,000 women in the Netherlands concluded that increased dietary intakes of acrylamide could raise the risk of endometrial and ovarian cancer by 29 and 78 per cent, respectively.