People living near facilities with EtO emissions are at a higher risk of developing breast cancer
A 2023 research paper found that people living within two miles of an EtO-emitting facility have a 60% increased risk of developing ductal carcinoma in situ (DCIS), one of the most common types of breast cancer. Furthermore, several other studies have come to the same conclusion, which strengthens the connection between ethylene oxide exposure and the development of breast cancer.
In addition to DCIS, listed below are the other typical types of breast cancer:
- Inflammatory breast cancer
- Invasive lobular carcinoma
- Lobular carcinoma in situ (LCIS)
- Male breast cancer
- Paget's disease of the breast
- Recurrent breast cancer
- Triple-negative breast cancer (TNBC)
- Ductal carcinoma in situ (DCIS)
The IARC, EPA, CDC, and other government bodies have included ethylene oxide in the list of Group 1 human carcinogens. The following are the usual signs and symptoms of breast cancer in both males and females:
- Lump, swelling, or pain in the breast area
- Unusual nipple discharge
- Skin changes in or around the breast area
- Changes in the size or shape of the breast
If you suffer from breast cancer that can be traced back to EtO exposure, then you may be eligible to file an ethylene exposure claim.
How ethylene oxide causes breast cancer
Major health agencies recognize ethylene oxide as a known human carcinogen due to its ability to harm DNA and cause cancer:
- The International Agency for Research on Cancer places EtO in Group 1 carcinogens, with evidence connecting EtO exposure specifically to breast cancer in humans
- The U.S. Environmental Protection Agency concludes that breathing it long-term increases cancer risk, including breast cancer in those exposed over many years
- The National Cancer Institute notes connections between EtO exposure and several cancers, including breast cancer, seen in some studies
Ethylene oxide functions as a direct-acting alkylating agent that chemically binds to DNA without metabolic activation. When inhaled, the gas gets into the bloodstream and disperses through the body, reaching breast tissue where it can harm DNA in mammary epithelial cells. EtO forms DNA adducts, particularly N7-(2-hydroxyethyl)guanine, which interfere with how DNA normally replicates. These adducts lead cells to make copying errors during replication, introducing mutations into the genetic code.
The genotoxic damage extends beyond simple mutations. EtO exposure induces several types of genetic damage:
- Chromosomal aberrations that mess up normal gene organization
- DNA strand breaks that fragment genetic material
- Mutations accumulating in cells throughout the body
According to assessments by the International Agency for Research on Cancer and the EPA, EtO causes cancer through this genotoxic mechanism. DNA damage starts a series of genetic and chromosomal changes that pile up over time and can lead to cancer.
Laboratory evidence shows that breast epithelial cells are vulnerable to damage from EtO. In vitro tests found DNA damage in cultured breast epithelial cells, increased with EtO dose, supporting a biological mechanism that could contribute to cancer development. This mechanistic evidence indicates breast tissue isn't immune to EtO's genotoxic effects, and the same DNA-damaging process causing other cancers operates in breast cells.
Occupational studies provide human evidence of the connection. Research following those employed at facilities using ethylene oxide observed a positive exposure-response pattern. Workers in the highest exposure group showed higher breast cancer incidence than lower exposure groups. Though associations vary across studies, this trend appearing in multiple research efforts suggests a causal relationship.
Government toxicology assessments acknowledge evidence for an association between EtO and breast cancer in human studies. They emphasize the genotoxic mode of action as key to cancer risk across multiple tissues, including breast tissue. The mechanistic foundation shows:
- EtO causes DNA damage via direct alkylation
- This produces adducts, mutations, and chromosomal aberrations
- These genetic changes can start carcinogenesis in breast tissue
The biological plausibility is supported by laboratory findings showing breast epithelial cells experience DNA damage after EtO exposure. Epidemiological signals from workplace studies show positive exposure-response trends for breast cancer risk, and environmental studies indicate increased risk for early-stage breast lesions near EtO emissions.