Military Environmental Exposures and Risk of Breast Cancer in Active-duty Personnel and Veterans: A Scoping Review

Objective(s): The effects of military environmental exposures (MEE) such as volatile organic compounds (VOCs), endocrine-disrupting chemicals (EDCs), tactile herbicides, airborne hazards and open burn pits (AHOBP), and depleted uranium on health are salient concerns for service members and Veterans. However, little work has been done to investigate the relationship between MEE and risk of breast cancer.

Data Sources: We conducted a scoping review on MEE, military deployment/service, and risk of breast cancer among active-duty service members and Veterans. PRISMA was used. PubMed, Embase, and citations of included articles were searched, resulting in 4,364 articles to screen: 28 articles were included.

Study Selection: Covidence software was used to collate and screen the articles. Four authors (AIB, DJJ, DKG, MTA) screened titles/abstracts and full-texts and met weekly to resolve disagreements through discussion. The database search was conducted on June 16, 2023, and resulted in a total of 4,510 articles. After the removal of 1,482 duplicates, 3,028 titles and abstracts were screened and 2,865 were excluded. A total of 163 full-texts were assessed, of which 11 were included. After screening an additional 1,336 citations from the included articles, 17 were retained for a final total of 28 articles.

Data Extraction: Data extraction was completed by four authors (AIB, DJJ, DKG, MTA) with each paper receiving at least two checks for accuracy and included the following headings: author/publication year, sample characteristics, sample size, exposure, results, warfare era/service years, and diagnosis years

Data Synthesis: Most papers on military deployment and military service found a lower/equivalent risk of breast cancer when comparing rates to those without deployment or civilians. Exposure to VOCs due to military occupation or contaminated groundwater was associated with a slightly higher risk of breast cancer. Exposure to Agent Orange was not associated with an increased risk of breast cancer. Evidence regarding EDCs was limited. No paper directly measured exposure to AHOBP or depleted uranium, but deployments with known exposures to AHOBP or depleted uranium were associated with an equivalent/lower risk of breast cancer.

Conclusions: Women are the fastest growing population within the military, and breast cancer poses a unique risk to women Veterans who were affected by MEE during their service. Unfortunately, the literature on MEE and breast cancer is mixed and limited, in part due to the Healthy Soldier Paradox and poor classification of exposure(s).

Author(s) Disclosures: Dr Adamson has no disclosures.