Cancer incidence and exposure to 4,4'-methylene-bis-ortho-chloroaniline (MbOCA).
OBJECTIVE
To monitor the occurrence of cancer in a recently defined cohort of UK workers engaged in the manufacture of polyurethane elastomers using 4,4'-methylene-bis-ortho-chloroaniline.


METHODS
A cohort of 308 male production workers from seven factories have been enumerated. All employees had a minimum of 12 months employment and were first employed at one of the participating factories in the period 1973-2000. Mortality and cancer incidence data for the period 1979-2007 were compared with expected values based on national rates.


RESULTS
Mortality from all cancers combined was below the expected value [observed (Obs) 5, standardized mortality ratio (SMR) 68]. There was a single death from bladder cancer (SMR 560). The incidence of all cancers combined was also below expectation [Obs 9, standardized registration ratio (SRR) 77]. Site-specific incidence was unexceptional except there was a non-significant excess of bladder cancer based on two cases (SRR 328).


CONCLUSIONS
The findings for bladder cancer should be treated with caution as they relate to a relatively early period of follow-up and are based on very small numbers.
Dost
Abid
A
British Rubber and Polyurethane Products Association Limited, London, UK. adost@brppa.co.uk
Straughan
J K
JK
Sorahan
Tom
T
D000395:Air Pollutants, Occupational / Q000633:toxicity* / Q000652:urine; D002617:Chemical Industry; D015331:Cohort Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008753:Methylenebis(chloroaniline) / Q000633:toxicity*; D009369:Neoplasms / Q000139:chemically induced / Q000453:epidemiology*; D016273:Occupational Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D011140:Polyurethanes / Q000138:chemical synthesis; D012907:Smoking / Q000453:epidemiology; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000453:epidemiology
D000395:Air Pollutants, Occupational; D011140:Polyurethanes; D008753:Methylenebis(chloroaniline)