Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX6-197
Table AX6-7.4 (cont’d). Other Studies of Lead Exposure and Cancer
Reference, Study
Location, and Period Study Description Pb Measurement Findings and Interpretation
Canada
Risch et al. (1988)
Canada
1979-1982
Siemiatycki et al.
(1991)
Canada
Case-control design.
Cases: 826 Canadian men with
histologically confirmed bladder cancer
during 1979-1982.
Controls: 792 controls from
Canadian population, matched on age,
gender, and area.
Odds of exposure to Pb for cases vs.
controls were computed, adjusted for
smoking and other risk factors.
Case-control design.
Cases: 3,730 various histologically
confirmed cancers.
Controls: specific cancer types were
compared with other cancers as a control
group, excluding lung cancer.
Separate subgroup analysis was
restricted to French Canadians.
Subjects were interviewed
regarding length of
occupational exposure to Pb
compounds, as well as 17 other
substances.
Occupational exposure to
293 substances, including Pb,
was estimated from interviews.
Exposure was classified as
“any”; a subgroup with
“substantial” exposure also was
identified.
OR (95% CI)
61 men ever exposed to Pb (smoking-adjusted):
2.0 (1.2, 3.5)
Trend per 10 yrs duration of exposure:
1.45 (1.09, 2.02)
No other substances showed significant associations with bladder
cancer.
Controlled for smoking, marital status, socioeconomic status,
education, ethnicity, and urban vs. rural residence.
No control for other occupational exposures. Low control interview
rate (53%), which could result in biased control sample.
OR (90% CI); number of cases
Any exposure to Pb:
Lung 1.1 (0.9, 1.4); 326
(French Canadians only)
Stomach 1.2 (1.0, 1.6); 126
Bladder 1.3 (1.0, 1.6); 155
(French Canadians only)
Kidney 1.2 (1.0, 1.6); 88
ORs rose in the “substantial” exposure subgroup for stomach and
lung, but not for bladder or kidney cancer.
Controlled for smoking but not for other occupational exposures.