Mortality and Childhood Residence Near the Radiologically Contaminated Coldwater Creek, St. Louis, Missouri
Background: Under the top-secret Manhattan Project, improperly stored radioactive byproducts from the processing of uranium contaminated Coldwater Creek in north St. Louis County, Missouri. We used the original 1958 Baby Tooth Survey (BTS) linked with the National Death Index (NDI) to investigate whether childhood residential proximity to the creek, as a proxy for radiation exposure, was associated with mortality. Methods: There were 43,876 eligible participants from the BTS (those outside Greater St. Louis and/or had incomplete covariates were excluded). In December 2023, the NDI was searched for BTS participants who have died. We estimated the hazard ratio (HR) and 95% confidence intervals between distance to Coldwater Creek (per 10km) and mortality (all-cause, cancer, and cardiovascular disease) adjusting for sex, birth year and census tract-level socioeconomic indicators. Results: Living closer to Coldwater Creek was associated with a higher rate of all-cause mortality (HR: 1.05; 95% CI: 1.01-1.09; p=0.01). There was suggestive evidence of an increased rate for cancer mortality: any cancer (HR: 1.06; 95% CI: 1.00-1.14; p=0.06), solid cancer (HR: 1.07, 95% CI: 1.00-1.16; p=0.06) and radiosensitive cancer (HR: 1.10; 95% CI: 1.00-1.21; p=0.05). There was no association with non-radiosensitive cancer and cardiovascular mortality. Conclusions: Our study provides new data that suggests living near Coldwater Creek in childhood was positively associated with the rate of all-cause mortality, and to a lesser extent cancer mortality, but not cardiovascular disease mortality. However, these findings should be interpreted cautiously given the lack of data on internal radiation exposure and individual socioeconomic status.