> On would think, our governments would be monitoring dioxins
Cancer mortality among workers in chemical plant contaminated with
dioxin.
TCDD can arise as a contaminant in the production of herbicides. It
causes chloracne in those exposed to it but its human carcinogenicity
has been a matter of dispute. We re****t here a mortality follow-up of
1583 workers (1184 men, 399 women) employed in a chemical plant in
Germany that produced herbicides, including processes contaminated
with TCDD. Production of TCDD was reduced from 1954 after an outbreak
of chloracne. Vital status up to 1989 was determined for 97.1% of
workers hired between 1952 and 1984, and 367 deaths (313 men, 54
women) were recorded. A malignant neoplasm was the underlying cause of
death in 93 men and 20 women. Standardised mortality ratios (SMR) were
calculated with, as references, national mortality statistics for West
Germany and deaths in a cohort of male gas workers; for total cancer
mortality they were 1.24 (95% confidence interval 1.00-1.52) and 1.39
(1.10-1.75), respectively, among men. Cancer mortality was increased
among men with 20 or more years of employment (SMR = 1.87 [Germany]
and 1.82 [gas workers]) and among men who began employment before 1955
(SMR = 1.61 and 1.87). The group with suspected highest exposure to
TCDD had SMRs of 1.42 and 1.78. Only 7% of cohort women worked in the
high exposure locations in the plant, compared with 39.6% of men, and
no increased risk of cancer mortality was observed among women; but
breast cancer mortality was raised (SRM = 2.15). These results,
together with a US occupational study and a German investigation of
accidental exposure, sup****t the hypothesis that TCDD is a human
carcinogen. PMID: 1681339
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