Robust association between the exposure to nitrate in drinking water and colorectal cancer

March 7, 2025

An integrated part of the MARCHES project is to update exposure-response functions for air pollution and drinking water nitrate from systematic reviews.

A review of the scientific literature has now revealed that there seems to be a robust association between the exposure to nitrate in drinking water with colorectal cancer.

"In a review of existing systematic reviews, we found that the most robust evidence exists for an association with colorectal cancer for which we have derived an updated exposure-response function through a new meta-analysis", said assistant professor, PhD Jörg Schullehner, Dept. of Public Health, Aarhus University.

The findings of this work have been presented for stakeholders, both nationally and internationally. 

International expert committee appointed by the Danish authorities: www.ft.dk/samling/20231/almdel/mof/bilag/610/2896743.pdf, February 2025

Scientific community: 36th Annual Conference of the International Society for Environmental Epidemiology, August 2024, in Santiago, Chile 

Stakeholders in Denmark, including environmental and health authorities): September 2023, Copenhagen 
https://www.sst.dk/da/arrangementer/2023/Temadag-og-webinar-om-drikkevand-og-sundhed

In the MARCHES project, the health-related economic societal costs of nitrate in drinking will be estimated using the approach of the EVA model (Economic Valuation of Air Pollution).
 
The results of the work made in the MARCHES project are planned to be published in an international scientific paper.  

There is also evidence for higher risks of other cancers and adverse birth outcomes after exposure to nitrate in drinking water, but the lack of sufficiently many good quality epidemiological studies makes it impossible to calculate reliable exposure-response functions at the moment. Read more: https://doi.org/10.1007/s40572-023-00404-9