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Your Environment. Your Health.

Halifax Project: Low Dose Theory Symposium

August 25, 2015
National Research of Environmental Health Sciences
Research Triangle Park, North Carolina

  • Welcome: Dr. Linda Birnbaum, Ph.D.
    Special Introduction: Margaret Kripke, Ph.D.
  • Speaker: Leroy Lowe
    The Halifax Project: Background, progress, and vision
    An overview of The Halifax Project, the approach taken and the outcome. Discussion on the use of cutting-edge disease biology to inform research on chemical exposures, mixture effects and risk assessment in matters related to environmental health.
  • Speaker: William Goodson, M.D.
    Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead
    A discussion on the implications of the findings from the project and the challenges ahead. How we create a research agenda for this set of problems – where to begin, easy questions, difficult questions, information gaps, and needs.

The contribution of environmental and occupational carcinogens to the cancer burden has long been debated because these carcinogens are among the most difficult to identify and quantify. The search for these carcinogens has focused mostly on identifying complete carcinogens-chemicals that can cause cancer on their own. But since the hallmarks of cancer were identified, our understanding of the underlying mechanisms of cancer has changed. We now know that cancer is a "multi-hit disease" where multiple pathways are affected. So is it possible that chemicals that aren't complete carcinogens are contributing to cancer by disrupting or triggering hallmark pathways?

That was the hypothesis examined by the Halifax Project, which convened 174 scientists from 26 countries and a wide variety of fields to assess the potential role of low dose chemical mixtures on the hallmarks of cancer. The scientists were divided into groups by hallmark and tasked with reviewing the literature to see if any of the 85 non-carcinogens they selected interacted or interfered with any of the hallmark pathways.

The results were released in June 2015 in a special edition of the journal Carcinogenesis with a capstone paper and separate review papers for each hallmark. The work has been catching the attention of scientists around the world including here at the NIEHS. 

An open-access copy of the Capstone paper can be found on the Carcinogenesis website where the rest of the articles are available as well.


Leroy Lowe

The Halifax Project: Background, Progress, and Vision
Leroy Lowe, President and Cofounder of Getting to Know Cancer

William Goodson, M.D.

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead
William Goodson, M.D., Senior Clinical Research Scientist at the California Pacific Medical Center

Margaret Kripke, Ph.D.

Environmental Carcinogenesis: Setting the Stage
Margaret Kripke, Ph.D., Chief Scientific Officer of the Cancer Prevention and Research Institute of Texas

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