Acrylamide in food
October 2006
Acrylamide is a chemical that can form in certain foods during cooking. The main mechanism for formation of acrylamide occurs from heating sugars with amino acids (specifically asparagine) in what is called a Maillard reaction. Maillard reaction products occur in cooking to produce the common cooking odours, flavours and texture of cooked food. The major foods in which acrylamide has been detected are fried or roasted potato products, coffee and cereal-based products (sweet biscuits, bread, rolls and toast) (see Background section).
In February 2005, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) reviewed the available data on the safety of acrylamide and concluded that its presence in food may be a health concern. A FSANZ scientist participated in the JECFA meeting.
Acrylamide has been shown to cause cancer in some studies in experimental animals although further studies are underway to better understand the significance of these results in relation to human health. These studies will be evaluated by JECFA when available. There is no direct evidence that acrylamide causes cancer in humans.
Since the discovery of acrylamide in food, there has been worldwide research into the mechanism of its formation as well as into methods to reduce the levels in specific foods. This work will continue and may lead to some reductions in consumer exposure in the future as a result of changes to food processing.
FSANZ is liaising with the Australian food industry to encourage and support them to examine ways in which manufacturing practices might be changed to reduce acrylamide formation in foods. In particular, FSANZ has urged the adoption of the ‘Acrylamide toolbox’ produced by the Confederation of the Food and Drink Industries of the EU (the CIAA) recently updated in September 2006 (version 9). This toolbox is aimed to assist food manufacturers to use the most current research appropriate for their products and manufacturing processes to reduce the formation of acrylamide, and is updated by the CIAA.
FSANZ has kept a watching brief on international developments regarding acrylamide and has undertaken a limited assessment of the dietary exposure of Australian consumers to acrylamide. FSANZ will continue to work with other national governments to better understand the potential health risk from exposure to acrylamide in the diet.
FSANZ continues to recommend that consumers should eat a balanced diet containing a range of healthy foods (including a broad range of fruit and vegetables), and to limit high fat and fried foods, as much as possible.
Background
In April 2002, the Swedish National Food Administration announced their findings that the chemical, acrylamide, could be found in starch-containing foods cooked at high temperatures, such as fried or roasted potato products and bread. The presence of this chemical in food was not known previously. The Swedish data have been confirmed more recently by studies in the UK.
Acrylamide is more commonly known as an industrial chemical used to prepare the polymeric material known as polyacrylamide, which is used as a flocculent for treating industrial wastewater and, to a lesser extent, drinking water, as well as having other industrial uses. There is a guideline level for acrylamide in Australian drinking water of 0.0002 mg/L. This guideline level is not based on adverse health effects, but rather on the lowest achievable level from its use as a flocculent.
While there is a considerable amount of information available regarding the potential health consequences of exposure to acrylamide at the high levels encountered in an industrial environment, the health consequences of exposure to the low levels found in foods are less clear. There are two areas of concern, namely potential toxicity to the nervous system and potential genetic damage that may lead to cancer.
Acrylamide is known to cause toxicity to the nervous system in animals and humans at very high levels of exposure, but the threshold for this effect is at a level of exposure that is far greater than the expected exposure from food. Consumption of food where acrylamide has been detected should not result in nerve damage.
The other health concern regarding acrylamide is its potential to cause genetic damage that may lead to cancer. On this matter, the available data are less clear and, although there is no evidence from human studies to link acrylamide exposure to increased cancer incidence, there is some evidence from animal studies to suggest such a link. Further information will be required to clarify whether low-level exposure to acrylamide in food can increase the risk of cancer in humans.
In order to address the concerns raised by the Swedish studies, the World Health Organization (WHO) organised an expert consultation in June 2002 to review and evaluate existing research data relevant to establishing the health consequences of the presence of acrylamide in foods. A summary report of the outcome of the consultation can be found on the WHO website as well as the full meeting report.
The consultation identified acrylamide in food as a major concern but also recognised the paucity of data on the safety of acrylamide and the need for more information on the mode of formation and levels of acrylamide in foods. The consultation called for an international effort to share information as part of the ongoing investigations. Members of the consultation also provided advice to minimise whatever risk exists: avoid cooking food excessively, moderate consumption of fried and fatty foods and eat a balanced and varied diet.
In October 2002, articles in the journal Nature confirmed earlier observations that acrylamide may be formed in foods during baking and frying, but has not been found in raw food, or food cooked at the lower temperatures reached during boiling.
The authors showed that acrylamide is formed during the Maillard reaction. Products of the Maillard reaction are responsible for much of the flavour and colour associated with fried, roasted and baked foods. This reaction requires sugars, proteins (or free amino acid) and high temperatures to proceed. Model systems used by the authors showed that heating the amino acid asparagine with glucose at 185°C results in most of the asparagine reacting to form acrylamide.
A report of an epidemiological study published in the British Journal of Cancer [January 2003] may help to allay some of the concerns associated with the presence of acrylamide in food. The study examined retrospectively the level of intake of acrylamide over 5 years in a group of cancer patients in Sweden compared with healthy controls. The researchers found “a lack of an excess risk, or any convincing trend, of cancer of the bowel, bladder or kidney in high consumers of fourteen different food items with a high or moderate range of acrylamide content”. While epidemiological studies of this type can never be considered conclusive, the reported results support previous studies which have failed to link acrylamide intake with human cancer.
The US Food and Drug Administration (US FDA) Center for Food Safety and Applied Nutrition in May 2006 reported their 2006 Exposure Assessment for Acrylamide and compared these results to the 2003, 2004 and 2005 survey results. The FDA analysed a number of US food products for acrylamide. The conclusion from this work is that the consumption of acrylamide for the US population has not changed over the period of 2003 to 2006 from the exposure assessments carried out. The FDA have also concluded that all members of the population (at least all people greater than 2 years old) consume acrylamide as part of their diet, since acrylamide is found in many types of food of a standard diet.