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Bladder tumors in two young males occupationally exposed to MBOCA.

Ward E; Halperin W; Thun M; Grossman HB; Fink B; Koss L; Osorio AM; Schulte P
Am J Ind Med 1988; 14(3):267-272
The case studies of bladder tumors occurring in two young men occupationally exposed to 4,4'-methylenebis(2-chloroanaline) (101144) (MBOCA) were reported. The noninvasive papillary tumors were identified in a screening study of 540 workers exposed to MBOCA during its production at a chemical factory from 1968 to 1979. The first phase of the study involved microscopic cytologic examination of two morning urine samples obtained from 370 of the workers who had been employed at the facility during the years when MBOCA was produced. Cystoscopy was then performed on 67 of the workers observed to have either at least five red blood cells per low power field, cytologic diagnoses of atypia in the initial examination, or job histories suggesting that their exposure to MBOCA was among the highest of the sampled workers. The tumors were detected in two nonsmoking males under the age of 30. One subject was a 28 year old man who was found to have seven red blood cells per low power field and intermittent low level hematuria; a noninvasive papillary transition grade 1-2 cell tumor was revealed upon cystoscopy and was excised. The other subject was a 29 year old man who was offered cystoscopy because of his history of exposure to MBOCA; a papillary urothelial grade 1 neoplasm was found. As the prevalence of clinically apparent tumors in US males aged 25 to 29 is only one per 100,000 per year, the authors conclude that the detection of the tumors in young nonsmoking males is consistent with the hypothesis that MBOCA induces bladder neoplasms in humans; MBOCA should therefore be treated as a potential occupational carcinogen.
NIOSH-Author; Carcinogens; Cancer-rates; Bladder-cancer; Occupational-exposure; Occupational-hazards; Tumorigens; Worker-health; Chemical-factory-workers; Anilines
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Journal Article
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American Journal of Industrial Medicine
Page last reviewed: January 28, 2022
Content source: National Institute for Occupational Safety and Health Education and Information Division