# Evaluation of the Relationship Between Nitrate Use and the Prevalence of Colorectal Cancers in the United States

## TL;DR

This study examined if nitrate in drinking water is linked to colorectal cancer rates in the U.S., but found no significant connection.

## Contribution

The study provides new ecological evidence on the relationship between nitrate exposure and colorectal cancer at the state level.

## Key findings

- No significant association was found between nitrate concentrations and colorectal cancer incidence.
- Correlations observed were weak and not statistically significant.
- Results suggest the need for individual-level studies to explore this relationship further.

## Abstract

Background

Exposure to nitrate through contaminated drinking water has been suggested as a potential risk factor for colorectal cancer (CRC). However, ecological evidence across the U.S. states remains limited. This study aims to examine the association between average nitrate concentrations and CRC incidence across 31 U.S. states.

Methods

An ecological analysis was conducted using data from the Centers for Disease Control and Prevention’s (CDC's) Environmental Public Health Tracking Network and United States Cancer Statistics (2017-2021). Simple linear regression and Pearson correlation analyses were performed, stratified by gender.

Results

No significant associations were observed between nitrate concentrations and CRC incidence in both strata. Correlations were weak and non-significant.

Conclusions

In our study, state-level nitrate exposure was not significantly linked to CRC incidence. Further individual-level studies are recommended.