Ethylene oxide emissions and incident breast cancer and non-Hodgkin lymphoma in a US cohort.

Abstract

BACKGROUND:

Ethylene oxide (EtO) is a carcinogenic gas used in chemical production and to sterilize medical equipment that has been linked to risk of breast and lymphohematopoietic cancers in a small number of occupational studies. We investigated the relationship between environmental EtO exposure and risk of these cancers.

METHODS:

Using the US Environmental Protection Agency's Toxics Release Inventory, we estimated historical exposures for National Institutes of Health-AARP Diet and Health Study participants enrolled in 1995-1996. We constructed 2 metrics at 3, 5, and 10 km: 1) distance between residences and EtO-emitting facilities, weighted by the proportion of time the home was downwind of each facility, and 2) distance-weighted, wind direction-adjusted average airborne emissions index (AEI=∑[lbs EtO/km2]). We estimated risk (hazard ratio [HR], 95% confidence interval [CI]) of incident breast cancer (in situ and invasive) among postmenopausal women (n = 173 670) overall and by tumor estrogen receptor status and non-Hodgkin lymphoma in the full cohort (n = 451 945).

RESULTS:

We observed an increased risk of breast cancer associated with EtO-emitting facilities within 10 km (HR[≤10vs>10] = 1.05, 95% CI = 1.00 to 1.10) that appeared stronger for in situ (HR[≤10vs>10] = 1.13, 95% CI = 1.00 to 1.27) than invasive (HR[≤10vs>10] = 1.03, 95% CI = 0.97 to 1.09) disease. Risk of breast cancer in situ was also increased in the top AEI quartiles, and associations weakened with larger distances (HR[Q4vs0] = 1.60, 95% CI = 0.98 to 2.61; HR[Q4vs0] = 1.28, 95% CI = 0.92 to 1.79; HR[Q4vs0] = 1.25, 95% CI = 1.02 to 1.53 at 3, 5, and 10 km, respectively). No differences in breast cancer risk were observed by estrogen receptor status. We found no clear pattern of increased non-Hodgkin lymphoma risk.

CONCLUSIONS:

A novel potential association between EtO emissions and risk of in situ, but not invasive, breast cancer warrants additional evaluation.

• Authors: Rena R Jones, Jared A Fisher, Danielle N Medgyesi, Ian D Buller, Linda M Liao, Gretchen Gierach, Mary H Ward, Debra T Silverman
• Journal: Journal of the National Cancer Institute (J Natl Cancer Inst) Vol. 115 Issue 4 Pg. 405-412 (04 11 2023) ISSN: 1460-2105 [Electronic] United States
• PMID: 36633307 (Publication Type: Journal Article, Research Support, N.I.H., Intramural)
• Copyright: Published by Oxford University Press 2023.

Chemical References

• Ethylene Oxide
• Receptors, Estrogen

Topics

• Humans
• Female
• Breast Neoplasms (epidemiology, etiology)
• Ethylene Oxide (adverse effects)
• Receptors, Estrogen
• Lymphoma, Non-Hodgkin (epidemiology, etiology)
• Risk
• Risk Factors