Environment and Breast Cancer: Science Review

Occupational exposure to estrogenic chemicals and the occurrence of breast cancer: an exploratory analysis
Aschengrau, A., Coogan, P. F., Quinn, M., Cashins, L. J. American Journal of Industrial Medicine. 1998. 34:1, 6-14.

Topic area
Environmental pollutant - Occupation
Environmental pollutant - Occupation
Study design
Population based case-control
Population based case-control
Funding agency
Other: Massachusetts Department of Public Health
Other: Massachusetts Department of Public Health

Study Participants
Number of Cases
261
261
Menopausal Status
Post menopausal
The menopausal status of women included in this study is listed here.
Pre menopausalPost menopausal
Number of Controls
Controls: 753
Controls: 753
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
Upper Cape Cod residents diagnosed in 1983-1986 and controls, participating in the Upper Cape Cod Cancer Incidence Study.

Exposure Investigated
Exposures investigated
Assessment of "possible" or "probable" job exposure based on NIOSH National Occupational Exposure Survey database to 18 chemicals identified as estrogenic in the ESCREEN MCF-7 bioassay.
Assessment of "possible" or "probable" job exposure based on NIOSH National Occupational Exposure Survey database to 18 chemicals identified as estrogenic in the ESCREEN MCF-7 bioassay.
How exposure was measured
Job history
Job history
Exposure assessment comment
Unvalidated classification of jobs.
Unvalidated classification of jobs.

Statistical Analysis
Breast cancer outcome investigated
Primary breast cancer
Primary breast cancer
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
No
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.
Breast cancer risk factors controlled.
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
Description of major analysis
Referent group is women with no exposed job history.
Referent group is women with no exposed job history.
Strength of associations reported
40% of cases and 38% of controls had a job with probable or possible exposure. Only PCBs and 4-octylphenol were associated with moderate increases in breast cancer risk.
PCBs adjusted OR 3.2 (0.8-12.2), 5 exposed cases, 6 exposed controls.
4-octylphenol adjusted OR 2.9 (0.8-10.8), 6 exposed cases, 5 exposed controls.
Nursing accounted for 47% of jobs with probable exposure to nonylphenol, 13% of jobs with probable exposure to bisphenol A, 13% of jobs with probable exposure to butyl benzyl phthalate, 22% of jobs with probable exposure to 4 ter butyl phenol. Food handlers accounted for 41% of jobs with probable exposure to BHA. Electronics workers were 14% of jobs with probable exposure to bisphenol A.
40% of cases and 38% of controls had a job with probable or possible exposure. Only PCBs and 4-octylphenol were associated with moderate increases in breast cancer risk.
PCBs adjusted OR 3.2 (0.8-12.2), 5 exposed cases, 6 exposed controls.
4-octylphenol adjusted OR 2.9 (0.8-10.8), 6 exposed cases, 5 exposed controls.
Nursing accounted for 47% of jobs with probable exposure to nonylphenol, 13% of jobs with probable exposure to bisphenol A, 13% of jobs with probable exposure to butyl benzyl phthalate, 22% of jobs with probable exposure to 4 ter butyl phenol. Food handlers accounted for 41% of jobs with probable exposure to BHA. Electronics workers were 14% of jobs with probable exposure to bisphenol A.
Results Comments
Low statistical power.
Low statistical power.

Author address
Department of Epidemiology and Biostatistics, Boston University School of Public Health, Boston, Massachusetts.
Department of Epidemiology and Biostatistics, Boston University School of Public Health, Boston, Massachusetts.
Controls participation rate
Greater than 70%
Greater than 70%