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The BCERF program on the Cancer Risks of Environmental Chemicals in the Home and Workplace closed on March 31, 2010. No further updates will be made to this web site. Please go Cornell University’s eCommons web site to access BCERF’s archived research and educational materials (

The Agricultural Health Study

The Agricultural Health Study (AHS) is a large, long-term study of farm families and commercial pesticide applicators. The study includes 89,658 enrollees from Iowa and North Carolina. Enrollment began in 1993. Data is now being analyzed to assess links between agricultural practices including pesticide use and cancer risk. (Many other health effects are also being studied including respiratory and reproductive health and diseases of the nervous system.)

Why Study Farmers?
Previous research indicates that although agricultural workers may live longer and are healthier in many ways than the general population, they experience higher rates of some cancers and other diseases. The AHS is focusing on farmers and their families in order to better understand both how agricultural chemical exposures can affect risk of cancer and other diseases and what factors may work to promote good health.

What Has the Study Found So Far?
While the AHS is still ongoing, early research findings have already been reported. One important finding of the study is that the enrollees experience lower overall cancer rates than the general public. (This fits with previous findings.) Other findings include the suggestion of an association between exposure to specific pesticides and higher risk of specific cancers. The suggested associations include: prostate cancer and methyl bromide, immune/blood cancers and alachlor, lung cancer and chlorpyrifos, and some evidence of increased breast cancer associated with exposure to several pesticides. Much more detail on the findings is in the feature article in The Ribbon, Vol. 10, Issue 2. The breast cancer risk findings are explored in a research commentary in The Ribbon, Vol. 10, Issue 2. The full edition of The Ribbon, Vol. 10, Issue 2 is available as a PDF file.

BCERF Fact Sheet 54, Farm Family Pesticide Exposure: New Pathways for Understanding Risk, explains findings from the study. The Chemicals fact sheet collection includes many of the chemicals being studied. Detailed Critical Evaluations on several of the chemicals compile and critique scientific evidence of the chemical's potential to affect breast cancer risk.

Uncovering Healthy Habits
The AHS is also studying pesticide exposure and safety practices enrollees use to minimize exposure. The study is helping investigators understand common pesticide application practices and to measure what benefits are provided by different precautions.

Community Connections
The AHS is committed to communication with enrollees and the public. Communication centers have been established in both Iowa and North Carolina. Because of this commitment, a lot of information is freely available to anyone who wants to know more about the study or its findings.

Find Out More

Fact Sheet
BCERF Fact Sheet 54, Farm Family Pesticide Exposure: New Pathways for Understanding Risk, explains findings from the study.

The Agriculural Health Study web site includes an extensive list of resources on their publications page.

Educational Web Site
"Understanding the Agricultural Health Study" includes sections on Pesticide Exposure, Health Findings, and Resources, as well as an overview of the AHS study, downloadable resources, and slide presentations.

Slide Presentation
The "Understanding the Agricultural Health Study" (for pesticide applicators and pesticide safety education audiences) slide presentation inlcudes speakers notes.

Supported by:
National Cancer Institute (NCI)
National Institute of Environmental Health Sciences (NIEHS)
The U.S. Environmental Protection Agency (EPA)
National Institute for Occupational Safety and Health (NIOSH)
The National Center on Minority Health and Health Disparities (NCMHD)
(Funds an effort to study cancer and non-cancer disease outcomes among African-American farmers in North Carolina.)