Abstract LB-16: Breast cancer risk in association with occupational exposure to organic solvents.

Abstract

Abstract Background: Organic solvents are widely used in occupational settings as adhesives, degreasing agents and cleaning products, and in the production of plastics and textiles. Several solvents have been recognized as human carcinogens; however, there is limited data on solvent exposure and the risk of breast cancer. The objective of this study was to examine the relationship between occupational exposure to organic solvents and breast cancer among women enrolled in the Sister Study. Methods: The Sister Study is a prospective cohort of over 50,000 US and Puerto Rican women aged 35-74 with a family history of breast cancer; enrollment and completion of baseline questionnaires occurred between 2004 and 2009. This analysis includes 47,763 women who reported working outside the home. We categorized occupational solvent exposure using baseline data on self-reported use of solvents on each job held for 12 months or longer. Women were followed for breast cancer incidence through 2012. Cox regression analyses were performed, adjusting for established breast cancer risk factors, including parity and age at first birth. Preliminary Results: A total of 1,596 women were diagnosed with invasive or in situ breast cancer during follow-up. Overall, there was no increased risk of breast cancer associated with lifetime use or duration of exposure to solvents (HR: 0.93, 95%CI: 0.79-1.09, p trend = 0.26). Among parous women, those who worked with solvents for five or more years prior to their first birth had an increased risk of breast cancer compared to women who never worked with solvents (HR: 2.12, 95%CI: 0.94-4.80, p trend = 0.02). Among all women, an increased risk was seen for solvent-exposed assemblers and fabricators (HR: 2.28, 95%CI: 1.13-4.57), and non-significantly elevated risks were noted among solvent-exposed cooks and nurses. Conclusions: These findings suggest that occupational exposure to organic solvents prior to first birth, a critical period of breast tissue differentiation, may result in increased vulnerability for breast cancer. Our results also give some indication of increased risks for solvent-exposed women in production, service and healthcare occupations. Future studies on solvent-related breast cancer risk should focus on exposure time window and types of organic solvents used across different occupational settings. Citation Format: Christine Ekenga, Christine G. Parks, Aimee A. D'Aloisio, Lisa A. DeRoo, Dale P. Sandler. Breast cancer risk in association with occupational exposure to organic solvents. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-16. doi:10.1158/1538-7445.AM2013-LB-16