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

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.