Mortality among chemical plant workers exposed to acrylonitrile and other substances.
OBJECTIVE
To examine the association between exposure to acrylonitrile (AN) and cancer mortality by performing an independent and extended historical cohort study of workers from a chemical plant in Lima, Ohio included in a recent NCI-NIOSH study.


METHODS
Subjects were 992 white males who were employed for three or more months between 1960 and 1996. We identified 110 deaths and cause of death for 108. Worker exposures were estimated quantitatively for AN and qualitatively for nitrogen products. Statistical analyses included U.S. and local county-based SMRs and internal relative risk regression of internal cohort rates.


RESULTS
No statistically significant excess mortality risks were observed among the total cohort for the cancer sites implicated in previous studies: stomach, lung, breast, prostate, brain, and hematopoietic system. We observed a statistically significant bladder cancer excess based on four deaths (SMR=7.01, 95% CI=1.91-17.96) among workers not exposed to AN. Among 518 AN-exposed workers, we observed a not statistically significant excess of lung cancer based on external (SMR=1.32, 95% CI=.60-2.51) and internal (RR=1.98, 95% CI=.60-6.90) comparisons. Although the trends were not statistically significant, exposure-response analyses of internal cohort rates showed monotonically increasing lung cancer rate ratios with increasing AN exposure, with RRs exceeding 2.0 in the highest exposure categories.


CONCLUSIONS
With the possible exception of lung cancer, this study provides little evidence that exposure to AN at levels experienced by Lima plant workers is associated with an increased risk of death from any cause including the implicated cancer sites.
Marsh
G M
GM
Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15621, USA. gmarsh+@pitt.edu
Gula
M J
MJ
Youk
A O
AO
Schall
L C
LC
D000181:Acrylonitrile / Q000009:adverse effects*; D000328:Adult; D001932:Brain Neoplasms / Q000401:mortality; D001943:Breast Neoplasms / Q000401:mortality; D002617:Chemical Industry; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D019337:Hematologic Neoplasms / Q000401:mortality; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009314:National Institute for Occupational Safety and Health, U.S.; D009316:National Institutes of Health (U.S.); D009369:Neoplasms / Q000401:mortality*; D017672:Nitrogen Compounds / Q000009:adverse effects*; D016273:Occupational Exposure; D009820:Ohio / Q000453:epidemiology; D011471:Prostatic Neoplasms / Q000401:mortality; D012044:Regression Analysis; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000401:mortality; D014481:United States; D001749:Urinary Bladder Neoplasms / Q000401:mortality
D017672:Nitrogen Compounds; D000181:Acrylonitrile