Systematic literature review and meta-analysis of a commonly used chemical

Breast Cancer Risk in Office Workers

Our team conducted a systematic literature review and meta-analysis of studies of lympho-hematopoietic cancers (LHC) and breast cancer risk among people who are occupationally exposed to ethylene oxide (EO): a highly reactive chemical produced in large volumes. EO is used primarily as an intermediate in the production of several industrial chemicals, and derivatives of it are commonly used in several industries, including plastics, polyester fibers, detergents, and ethylene glycol antifreeze. Two primary sources of occupational exposure to EO are from production facilities and sterilization operations.

We performed a literature search for articles available in PubMed and Web of Science databases to identify literature and subsequently systematically searched the reference lists of identified studies, published review papers and meta-analyses, and relevant government or regulatory documents. We qualitatively reviewed 30 studies and conducted meta-analyses on 13 studies. Pooled risk estimates were calculated using random effects models, stratifying by occupational group, cancer type, and decade of publication.

Our systematic literature review and meta-analysis discovered that the most informative epidemiology studies, which were published in the 2000s and 2010s, do not support the conclusion that exposure to EO is associated with an increased risk of LHC or breast cancer. In addition, evaluations of workers exposed during sterilization processes do not support the conclusion that EO exposure is associated with an increased risk of breast cancer.