Evidence From Humans
 
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Chronic diseases and early exposure to airborne mixtures: Part III. Potential origin of pre-menopausal breast cancers
Argo, J. J Expo Sci Environ Epidemiol. 2010. 20:2, 147-59.
Topic area
Environmental pollutant - Air pollution
Study design
Population-based case-control
Study Participants
Number of Cases
Not reported
Menopausal Status
The menopausal status of women included in this study is listed here.
Analysis restricted to premenopausal status
Number of Controls
Not reported
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
This study uses data from the Environmental Quality Database (EQDB), collected between the years 1993-1995. Subjects resided within 25 km of kraft mills, sulfite mills, coke ovens, oil refineries, copper, nickel, and lead/zinc smelters in Canada (except Quebec and New Brunswick) in 1967-1970 and were aged in utero <31 years.
Exposure Investigated
Exposures investigated
Self-reported lifetime residence within 25km of kraft and sulfite mills, coke ovens, oil refineries, copper, nick and lead/zinc smelters operating in Canada in 1967-1970, and residential proximity to sources of dioxins, dimethyl sulfate (DMS), and SO2 fro
How exposure was measured
GIS/geographic location
Exposure assessment comment
By including adult cases who were exposed to airborne mixtures between 1967-1970 and were diagnosed between 1993-1995, this study permits a minimum latency period of 23 years. All sources and subjects were geolocated using the Canadian postal code.
Early life exposures considered
When analyses were stratified by 5 year age groups (e.g. between in utero-5 years, between 5 and 10, etc.), risks were higher in the younger cohorts, although no test of trend reported.
Breast cancer outcome investigated
Primary incident breast cancer
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Gender, smoking
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Strength of associations reported
Distribution of breast cancer by age cohort and proximity to industry:
Kraft mill:
Overall: RR 4.9 (95% CI 3.2-6.2)
In utero: RR 20.7 (95% CI 8.4-50)
10
Sulfite mill:
Overall: RR 5.2 (95% CI 4.2-6.6)
In utero: RR 8.1 (95% CI 4.8-13)
10
Coke oven:
Overall: RR 6.1 (95% CI 4.6-7.9)
In utero: RR 9.5 (95% CI 5.3-17.0)
10
Petroleum refinery:
Overall: RR 8.0 (95% CI 7.2-8.9)
In utero: RR 10.5 (95% CI 8.6-12.0)
10
Copper smelter:
Overall: RR 2.8 (95% CI 2.0-4.0)
In utero: RR 4.5 (95% CI 2.3-8.9)
10
Nickel smelter:
Overall: RR 4.4 (95% CI 3.2-6.0)
In utero: RR 7.0 (95% CI 3.3-14.0)
10
Lead/Zinc smelter:
Overall: RR 1.1 (95% CI 0.7-1.7)
In utero (9 cases): RR 1.8 (95% CI 0.6-5.4)
10
Results Comments
There was a significant correlation between excess breast cancer by residence to each industry and estimated exposures to process, boilers, DMS, dioxins, and flares (from oil refineries).
Author address
IntrAmericas Centre for Environment and Health, Box 101, Wolfe Island, Ontario, Canada K0H2Y0. iceh@kos.net
Reviewers Comments
A limitation to the ecologic design is the lack of individual risk factor information.