Risk of Mortality From Esophageal Cancer Among US Poultry Workers, 1950-2019

While research suggests poultry industry workers have an increased risk of cancer mortality, little is known about their risk of esophageal cancer mortality. We investigated the association between working with poultry and esophageal cancer mortality while concurrently investigating other occupational and nonoccupational risk factors amongst poultry industry workers.

We conducted a case-cohort analysis from a cohort of unionized workers in the United States (N = 46,816) and conducted follow-up for mortality from 1950 to 2019 with the National Death Index. Cases were those who died of esophageal cancer and a sub-cohort was randomly selected (N = 2666) for further analysis. We interviewed participants and relatives about their work and personal life. We used multivariable Cox proportional hazards regression to estimate the hazard of esophageal cancer mortality due to working with poultry among the full cohort and weighted regression for the sub-cohort and those interviewed. We conducted exploratory analyses to estimate hazard ratios (HR) and 95% confidence intervals (CI) for each interview question, adjusted for confounders, and computed a false discovery rate (FDR).

In the full and sub-cohort, working in a poultry plant was associated with an increased hazard of esophageal cancer mortality (HR = 1.62, 95% CI = 1.05, 2.50; and HR = 1.65, 95% CI = 1.03, 2.65, respectively). Among survey respondents, working in a poultry plant appeared to decrease the risk of esophageal cancer mortality (HR = 0.67; 95% CI = 0.34, 1.35).

Working in poultry plants may increase the risk of death from esophageal cancer, but further research is needed to validate these findings and explore potential mechanisms.