Envision zero breast cancer

Polycyclic aromatic hydrocarbons, or PAHs, are harmful chemicals created whenever organic materials like wood, oil, or coal are burnt. PAHs are also formed during grilling of meat or fish. This leaves behind an invisible, toxic footprint that most of us breathe in or eat every single day. Exposures come through outdoor and indoor sources like cigarette smoking, wood burning, wildfires, vehicle traffic, and grilling meat. These sources are often unavoidable in the modern world.

PAHs are known to have a direct link to reproductive hormone disruption in women and increase the risk of breast cancer. Though most PAH studies have focused on adults, recent papers published by Dr. Esther M. John at Stanford University and her colleagues focused on PAH exposure in young girls during puberty. The researchers explored whether PAHs are linked to early puberty, which increases the risk of breast cancer later in life.

Dr. Dimitri Abrahamson is a scientist at UCSF, working alongside Dr. Kimberly Badal in her ongoing chemical mixtures study. As a computational chemist using virtual laboratories, in addition to test tubes, Dr. Abrahamson’s expertise is in the connection of technology, medicine, and chemistry. Camille Sytko (Science Communications Intern) and Lianna Hartmour (Zero Breast Cancer Program and Communications Director) at the Collaborative for Health & Environment (CHE) had the opportunity to interview him to better understand the important role machine learning plays in the study, and what benefits machine learning may continue to bring to the field of environmental health.

In 2025, Zero Breast Cancer continued to thrive as part of the Collaborative for Health and Environment (CHE). Our ongoing work in multigenerational breast cancer risk reduction, survivorship, and research partnerships is moving us toward our vision of a world with zero breast cancer. Below we have spotlighted outcomes of some of our most impactful programs.