Persistent organic pollutants (POPs) are synthetic chemicals produced or released during industrial processes. Although their use has been banned for some and restricted for others after the Stockholm Convention, POPs remain contaminants of air, soil and water and accumulate during production in high-fat food items. There is some but not conclusive evidence for their role in cancer. This research project will improve our understanding of the role of POPs in the development of hormone-sensitive obesity-related cancers. We also aim to identify dietary, anthropometric, and other factors that may impact circulating POP concentrations to orient future targeted prevention strategies
Dr Charlotte Le Cornet
Background
Endocrine disruptor chemicals, including persistent organic pollutants (POPs), are produced or released during industrial or agricultural processes. Although their use has been more restricted from 2004, after the Stockholm Convention, they are widespread in the environment. About 90% of human exposure to POPs is due to dietary intake (fish, meat, egg, dairy) and accumulate in human adipose tissue. In interfering with endocrine and inflammation system, POPs have been shown to play a role in health issue such as obesity and diabetes. To date, prospective epidemiological studies are failing to reach consensus on the association between POP exposures and hormone-sensitive cancers in women, such as endometrial and breast cancers, for which obesity is an established risk factor.
Aims and objectives
Our overarching aim is to comprehensively evaluate the association of POPs with endometrial and postmenopausal breast cancers, accounting for adiposity. We will achieve this aim by accomplishing three objectives:
- Systematically review the literature on I/the concurrent association between POPs and body fatness, and II/ POPs to endometrial and breast cancer development.
- Investigate the association of POPs with endometrial and postmenopausal breast cancer risk, in a case-control study nested within the large EPIC cohort, which will include 305 matched pairs of endometrial, and 300 matched pairs of postmenopausal breast cancers. A total of 22 pre-diagnosis circulating POPs, including polychlorinated biphenyls (PCBs), and p,p’-dichlorodiphenyl-trichlorethan (p,p’-DDT) will be examined individually and combined. Modification of associations will be examined by BMI.
- Explore the relationships between POPs and dietary intakes, anthropometric, reproductive, lifestyle factors, and circulating biomarkers in 1,210 women.
How it will be done
The systematic review will be conducted using a framework for systematic reviews of mechanistic research developed by WCRF and the University of Bristol. Matched pairs of case-controls within the well-characterized EPIC cohort will be used to conduct the risk analysis between POP exposures and hormone-sensitive obesity-related cancers in women, allowing adjustment for a large panel of potential confounding factors.
Potential impact
We will provide the first comprehensive, systematic review of POPs as a potential effect modifier in associations between body fatness and endometrial and breast cancers. Additionally, findings from the risk analysis conducted within the EPIC population will provide further understanding of the role of POPs in hormone-sensitive obesity-related cancer development in women, and will potentially identify dietary, anthropometric, lifestyle, or reproductive factors which might impact POPs concentration in blood, and therefore on which, preventive action should be oriented to lower POPs concentration.