Acetylaldehyde-Cancer Risk Assessment

Author:  Suvash Shrestha
Institution:  Kathmandu Medical College, Nepal
Date:  April 2009

Researchers at the Centre for Addiction and Mental Health (CAMH) in Toronto and Chemical and Veterinary Investigation Lab in Karlsruhe (CVUA), Germany stated in a review published online in Addiction on 17th March 2009 that current risk assessments of acetaldehyde-induced cancer do not accurately portray risks associated with the disease. They also stated that alcoholic beverages carry the highest risk of acetaldehyde-induced cancer.

The organic compound acetaldehyde (CH3CHO) has long been classified as a possible carcinogen by the International Agency for Research on Cancer of World Health Organization. Earlier researchers have shown the association of acetaldehyde with different cancers, especially in the upper gastrointestinal tract. However, the risk of cancer induction has not been evaluated until now. Researchers at CAMH and CVUA have shown that, in addition to being the ultimate product of alcohol metabolism, acetaldehyde is freely present in alcoholic beverages. Also, the lifetime cancer risk for average exposure to alcoholic acetaldehyde is 7.6/10,000, while it's 1/1,000 in cases of high-risk scenarios such as contamination in unprocessed alcohol. Thus, alcoholic beverages are considered the greatest risk factor for acetaldehyde-induced cancer, despite there being other acetaldehyde-rich sources such as tobacco and smoke.

"The problem with acetaldehyde has been that, although it has been recognized as toxic by Health Canada some years ago, most risk assessments to date were based on one source of exposure only" said Dr. Jürgen Rehm, the lead scientist of the Toronto group and head of the Public Health and Regulatory Policies section at CAMH. As these estimations exclude other potential sources of the compound, they don't give the overall risk and often underestimate the level of acetaldehyde.

For example, the Public Health Agency in Toronto sets a limit for acetaldehyde level with a safety margin immediately following this limit in order to prevent harmful levels from being reached. However, for alcoholics and smokers, it can easily reach an alarming level. This happens because the Public Health Agency studied only the acetaldehyde level in air to estimate a safety level rather than all the possible sources.

On the basis of their study, Rehm and his co-workers have made some recommendations. Acetaldehyde should be reclassified, taking into account its newly discovered carcinogenic properties. Risk assessment should also include other potential sources of acetaldehyde and measures should be taken to minimize acetaldehyde to the lowest technically possible level.

Written By: Suvash Shrestha

Edited by: News and Features Editor Brittany Raffa and Professional Reviewer Renee Gilberti

Published by Falishia Sloan