Abstract
OBJECTIVES: An update of a study of workers exposed to 2- mercaptobenzothiazole (MBT) at a rubber chemicals plant in Nitro, West Virginia is reported. The earlier study found high rates of lung cancer, prostate cancer, and bladder cancer in these workers who also had potential exposure to 4-aminobiphenyl (PAB), a potent bladder carcinogen. METHODS: This cohort mortality study examines the mortalities of 1059 full time white male production workers employed at the plant from 1955 to 1977. A detailed exposure assessment was done on the 600 workers with exposure to MBT. Nine years of additional follow up to the previous study are added. RESULTS: It was found that MBT workers have expected rates of lung (standardised mortality ratio (SMR) = 1.0 95% confidence interval (95% CI) 0.7 to 1.5) and prostate (SMR = 0.9, 95% CI 0.2 to 2.3) cancer. There was an excess of bladder cancer among MBT workers who had definite exposure to PAB (SMR = 27.1, 95% CI 11.7 to 53.4), and MBT workers with potential exposure to PAB (SMR = 4.3, 95% CI 1.4 to 10.0). However, there were no deaths from bladder cancer among workers with no exposure to PAB (SMR = 0.0, 95% CI 0.0 to 24.7), although there were only 0.2 deaths expected. CONCLUSIONS: The potential confounding of exposure to an unknown portion of PAB in the MBT workers makes it impossible to evaluate risk of bladder cancer in this population at this time. However, exposure to MBT does not seem to increase the risk of most cancers including cancers of the lung and prostate.
Full Text
The Full Text of this article is available as a PDF (93.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- CASE R. A., HOSKER M. E., McDONALD D. B., PEARSON J. T. Tumours of the urinary bladder in workmen engaged in the manufacture and use of certain dyestuff intermediates in the British chemical industry. I. The role of aniline, benzidine, alpha-naphthylamine, and beta-naphthylamine. Br J Ind Med. 1954 Apr;11(2):75–104. doi: 10.1136/oem.11.2.75. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Collins J. J., Strauss M. E., Levinskas G. J., Conner P. R. The mortality experience of workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin in a trichlorophenol process accident. Epidemiology. 1993 Jan;4(1):7–13. doi: 10.1097/00001648-199301000-00003. [DOI] [PubMed] [Google Scholar]
- MELICK W. F., ESCUE H. M., NARYKA J. J., MEZERA R. A., WHEELER E. P. The first reported cases of human bladder tumors due to a new carcinogen-xenylamine. J Urol. 1955 Dec;74(6):760–766. doi: 10.1016/S0022-5347(17)67344-0. [DOI] [PubMed] [Google Scholar]
- Melick W. F., Naryka J. J., Kelly R. E. Bladder cancer due to exposure to para-aminobiphenyl: a 17-year followup. J Urol. 1971 Aug;106(2):220–226. doi: 10.1016/s0022-5347(17)61263-1. [DOI] [PubMed] [Google Scholar]
- Moses M., Lilis R., Crow K. D., Thornton J., Fischbein A., Anderson H. A., Selikoff I. J. Health status of workers with past exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin in the manufacture of 2,4,5-trichlorophenoxyacetic acid: comparison of findings with and without chloracne. Am J Ind Med. 1984;5(3):161–182. doi: 10.1002/ajim.4700050303. [DOI] [PubMed] [Google Scholar]
- Sorahan T., Pope D. Mortality study of workers employed at a plant manufacturing chemicals for the rubber industry: 1955-86. Br J Ind Med. 1993 Nov;50(11):998–1002. doi: 10.1136/oem.50.11.998. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Strauss M. E., Barrick E. D., Bannister R. M. Mortality experience of employees exposed to 2-mercaptobenzothiazole at a chemical plant in Nitro, West Virginia. Br J Ind Med. 1993 Oct;50(10):888–893. doi: 10.1136/oem.50.10.888. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Suskind R. R., Hertzberg V. S. Human health effects of 2,4,5-T and its toxic contaminants. JAMA. 1984 May 11;251(18):2372–2380. [PubMed] [Google Scholar]
- Zack J. A., Suskind R. R. The mortality experience of workers exposed to tetrachlorodibenzodioxin in a trichlorophenol process accident. J Occup Med. 1980 Jan;22(1):11–14. [PubMed] [Google Scholar]
