Multi-Generational Samples Allow Researchers to Search for Link Between Environmental Chemical Exposures During Pregnancy and Future Breast Cancer

A new study, released by the Public Health Institute’s Child Health and Development Studies in the August issue of Environment International, is one of the few studies to examine environmental chemical exposures during pregnancy and their relation to women’s risk to breast cancer later in life.

Typically, when women have breast cancer it’s difficult to trace the pathways on how they developed it. Multi-generational data spanning over 60 years from the Child Health and Development Studies (CHDS) allow a unique opportunity to look at current breast cancer cases, and then research and analyze environmental chemical exposures that took place during pregnancy years or even decades earlier when blood and other data were originally collected. Few such repositories exist, making the data—and the answers it may give to breast cancer pathways and prevention—both critical and rare.

During the study, researchers measured exposures during pregnancy and a woman’s responses to exposures during pregnancy, many years before she developed breast cancer, and compared them to women who did not develop breast cancer. Researchers used high-resolution mass spectrometry, which measured the exact mass of a compound or molecular structure of biospecimens gathered over decades from a pregnancy cohort in the CHDS and utilized data analysis to discover new environmental chemicals associated with maternal breast cancer. Breast cancer data was provided by the California Cancer Registry.

While more research on pathways is ongoing, early indicators from the study, Exposome Epidemiology for Suspect Environmental Chemical Exposures During Pregnancy Linked to Subsequent Breast Cancer Diagnosis, conducted in partnership with Emory University, include:

• Researchers identified suspect environmental chemicals that may be implicated in breast cancer development, including: an insecticide, nitromethylene-piperidine; a common commercial chemical, 2,4-dinitrophenol; a heterocyclic amine with diverse commercial applications, benzo[a]carbazole; a benzoate derivative which could be derived from natural products or environmental chemicals; and oxalate, which is also used as a cleaning agent.
• Researchers linked metabolomic pathways in pregnancy with pregnancy environmental factors and to future breast cancer.  Metabolome is a read out of how our genes have responded to conditions in our bodies due to either internal factors, like stress or our own hormones or external factors, such as diet, environmental or pharmaceutical chemicals.

Breast cancer is the leading type of cancer globally, accounting for 12% of all new annual cancer cases worldwide. The researchers looked at the exposome, which includes the total exposures we experience throughout our lives, including the food we eat, the air we breathe, objects we touch, the psychological stresses we face, and the activities we engage in.

This study was funded by the Department of Defense Breast Cancer Research Program, the National Institutes of Environmental Health Sciences, and the National Institute of Diabetes and Digestive and Kidney Diseases.

About the Child Health and Development Studies

The Child Health and Development Studies (CHDS) at the Public Health Institute, investigates how health and disease are passed on between generations—not only genetically, but also through social, personal, and environmental surroundings. Studies spanning over 60 years enable CHDS scientists to study health across generations and seek ways to prevent disease early in life.