Does an occupation at a tannery promote pancreatic cancer?

Introduction
Occupational environment makes an important contribution to the public health of workers and people living beside the enterprise.

Methods
The cohort of 3468 workers who were actively employed with a minimum of 6 months was retrospectively followed from 1 January 1953 to 31 December 2000 to calculate proportional mortality ratios (PMRs). 768 workers (328 women and 440 men) were died from different causes. The same cohort was additionally investigated by proportional cancer incidence ratios (PIRs) for 1990-2007 (167 cancer cases). Age and time standardization was implemented.

Results
We have shown the significant excess in mortality with pancreatic cancer (PMR=366% 95%CI=134 800) in women-workers of Dyeing and stuffing workshops (DSW). Significantly high mortality from pancreatic cancer was established among DSW female workers hired and discharged between 1962 and 1984 (PMR=654%, 95%CI=260-1340). It should be noted that this excess was indicated for DSW female workers with seniority more than 10 years. Further analysis (1990-2007) by PIRs did not show significant excess in pancreatic cancer in females, but considerably high level of pancreatic cancer was noted in males workers (PIR=298%; 95%CI=110-650), who were employed in DSW for more than 7 years in 70th - 80th. Also significantly high PIRs were established for male workers with lung cancer (PIR=164%; 95%CI=105-245). For all time no cases of nasopharyngeal cancers have been found. Also we did not show any significant excess in bladder and renal cancers.

Discussion
Our earlier mortality study also found non-significant excess in pancreatic cancer in males. We can suppose the role of Chromium in leather stained dust as a-promoting factor. The recent significance in males could be explained by longer latency for men than for women.