Introduction Colorectal cancer (CRC) is an important cause of morbidity and mortality. High intake of meat has been associated with increased risk of CRC in some studies but results are inconsistent. Instead of examining meat intake it may be appropriate to examine total meat-derived mutagenic activity (MDMA), which incorporates the mutagenic activity from identified and other yet unidentified chemical compounds in cooked meat.

Methods This case-control study used data from the Western Australian Bowel Health Study. It included 567 cases and 713 age and sex frequency matched controls, aged between 41 and 80 years. Meat consumption information was collected via self-administered questionnaires. Exposure to MDMA and predicted heterocyclic amine -derived mutagenic activity (PHDMA) was estimated by linking the meat data into a carcinogen database (CHARRED). The data were analysed using multivariable logistic regression.

Results ORs for increasing quartiles of MDMA indicated no association with CRC. Although the ORs for comparing subjects in the higher quartiles of PHDMA based on total and red meat consumption with lower quartiles of intake were less than one, none of these relationships were statistically significant. However, the PHDMA from white meat was associated with a non-significant increase in the risk of CRC (OR high compared with lowest quartile=1.17, 95% CI 0.83 to 1.64, p>0.30).

Conclusion Our study did not support the association between exposure to MDMA and the risk of CRC.