"Breast Cancer and the Environment: A Life Course Approach"

The volume emphasizes that there are many challenges to studying breast cancer risk, including the possibility that some exposures that may influence risk occur early in a woman's life, even in utero. The book recommends examining exposures at all stages of life, not just during adulthood, as well as taking a multidisciplinary approach to studies of breast cancer risk. It also emphasizes developing new methods for epidemiologic research, for accurately assessing exposure to potential risk factors, and for testing the cancer risk of chemicals and other substances.

Because data from human studies are often unavailable or inconclusive, the committee did not find strong evidence linking many suspected chemicals to breast cancer risk; only exposures to benzene, 1,3-butadiene, and ethylene oxide had "possible association[s]" with increased breast cancer risk. Several other chemicals, including BPA, had "biological plausibility as a hazard," but no human studies have confirmed an association with cancer risk.

Contents
ACRONYMS AND ABBREVIATIONS
SUMMARY
1 INTRODUCTION
Study Charge and Committee Activities
Approach to the Study
Topics Beyond the Scope of the Study
The Committee’s Report
References
2 BACKGROUND, DEFINITIONS, CONCEPTS
An Introduction to Breast Cancer
Breast Cancer Incidence in the United States
A Broad Perspective on the Environment
Investigating Whether Environmental Factors Are Related to Breast Cancer
Some Measures of Disease Risk
Summary
References
3 WHAT WE HAVE LEARNED FROM CURRENT APPROACHES TO STUDYING ENVIRONMENTAL RISK FACTORS
Scope of the Review
Discussion of Specific Environmental Factors
Summary
References
4 CHALLENGES OF STUDYING ENVIRONMENTAL RISK FACTORS FOR BREAST CANCER
Complexity of Breast Cancer
Studying Environmental Chemical and Physical Exposures Through Human Studies
Human Epidemiologic Study Design and Implementation
Studying the Role of Genetics in Breast Cancer
Gene–Environment Interactions
Implications of Genetic Variability for Understanding Risk for Breast Cancer
Studying Environmental Risk Factors Through Whole Animal and In Vitro Experiments
Summary
References
5 EXAMINING MECHANISMS OF BREAST CANCER OVER THE LIFE COURSE: IMPLICATIONS FOR RISK
Environmental Exposures Over the Life Course as Determinants of Breast Cancer Risk
Mechanisms of Breast Cancer Development
Possible Biologic Mechanisms for Alterations in Breast Cancer Risk Associated with Obesity
A Need to Consider Timing of Exposure Across the Life Course
References
6 OPPORTUNITIES FOR ACTION TO REDUCE ENVIRONMENTAL RISKS FOR BREAST CANCER
Recognizing Uncertainty of Benefits and Risks
Evidence-Based Opportunities for Action to Reduce Risk
Likely Opportunities to Act to Reduce Risk of Breast Cancer
Assessing the Potential Impact of Risk Reduction Efforts
Summary
References
7 RECOMMENDATIONS FOR FUTURE RESEARCH
Applying a Life-Course Perspective to Research on Breast Cancer
Targeting Specific Concerns
Epidemiologic Research
Research to Advance Preventive Actions
Testing to Identify Potential Breast Carcinogens
Understanding Breast Cancer Risks
Concluding Observations
References
APPENDIXES
A Agendas for Public Meetings
B Biographical Sketches of Committee Members
C Classification Systems Used in Evidence Reviews
D Summary Table on Estimates of Population Attributable Risk
E Glossary
F Ionizing Radiation Exposure to the U.S. Population, with a Focus on Radiation from Medical Imaging