New Study on CO Fracking Chemicals and Hormone Disruption

We received this letter from ecologist, author, and cancer survivor, Sandra Steingraber, Ph.D. She is an internationally recognized authority on the environmental links to cancer and human health.

Steingraber’s highly acclaimed book, Living Downstream: An Ecologist’s Personal Investigation of Cancer and the Environment presents cancer as a human rights issue. Originally published in 1997, it was the first to bring together data on toxic releases with data from U.S. cancer registries and won praise from international media including The Washington Post, Publishers Weekly, The Lancet, and The London Times.

Below she discusses an important new study on the connection between fracking chemicals and human health.

Dear friends in environmental health,

Pasted below and attached is a statement released today by Concerned Health Professionals of New York in response to the new study by Nagel et al. in Endocrinology.  This paper describes the endocrine-disrupting abilities of a dozen commonly used fracking chemicals and also reports estrogen- and androgen-disrupting activity in water samples collected near fracking sites in Colorado. 

These include samples taken from the Colorado River itself, whose watershed is intensely drilled and which provides water to 30 million people.  

Here in the United States, pregnant women, infants, children, and breast cancer patients live everywhere that drilling and fracking operations occur. No requirement exists for the screening of endocrine-disrupting chemicals used in these operations, nor even for basic disclosure of their identity.  Endocrine-disrupting chemicals are biologically persistent, potent in small doses, and capable of exerting time-delayed health effects that are not always immediately apparent after exposure. As Phil Landrigan and other have demonstrated, the developmental effects of population-wide, early life exposures also carry with them high medical costs.

For these and other reasons, it seems to me, the ethical response on the part of the environmental health community is to reissue a call that many have made already:  hit the pause button via a national moratorium on high volume, horizontal drilling and fracking and commence a comprehensive Health Impact Assessment with full public participation.  

Instead of merely praising the public health triumph of a nationwide ban on leaded paint and leaded gasoline at the beginning of our powerpoint presentations, I am suggesting that we stage a reenactment. 

Beyond that, there are other messages for us to ponder: 

  • Given these findings in Colorado, what are the possible public health effects of opening for fracking the Delaware River basin, which is a source of drinking water for at least 15 million people? 
  • What are the implications of intensive drilling in the Susquehanna River basin, which provides 45 percent of the freshwater to the Chesapeake Bay area?  
  • What are implications of opening up for drilling and fracking the heavily forested public lands near to Washington D.C.? 
  • And what are our responsibilities in both documenting human harm and in working to prevent it? 

This study also makes clear for me that endocrine disruption is not solely a public health issue relevant to the materials economy.  It is also part of the struggle to reform our energy system.  Indeed the two are inextricably intertwined:  it is the shale gas boom—with all the EDCs involved in the extraction process—that is now driving the resurgent boom in plastics and farm chemicals manufacturing—with all the EDCs so created.  This cheap abundance of petrochemicals undermines our collective efforts to bring about meaningful toxic chemical reform and investments in green chemistry and sustainable agriculture

, while the cheap abundance of natural gas undermines efforts to decarbonize our energy system and address climate change in meaningful ways. 

I welcome your further thoughts.  Feel free to share the statement below. I have a full-text, pre-print pdf of the Nagel study, which I can share privately.  I understand from a conversation with Endocrinology editor Scott Harman this morning that the final, full text print version of the study will be available in about two months. 

You will also find our statement—along with a searchable archive of information on the health effects of shale gas development—at

kind regards,


Sandra Steingraber, PhD

Distinguished Scholar in Residence

Department of Environmental Studies and Sciences

Ithaca College

co-founder, Concerned Health Professionals of New York, New Yorkers Against Fracking

December 17, 2013 

Statement by Concerned Health Professionals of New York

in Response to a New Study on Hormone-disrupting Contaminants

in Water Near Colorado Drilling Sites*

Of the 700-plus chemicals that can be used in drilling and fracking operations, more than 100 are known or suspected endocrine disruptors. Unique among toxic agents, endocrine-disrupting chemicals (EDCs) interfere with hormonal signals, are biologically active at exceedingly low concentrations, and, when exposures occur in early life, can alter pathways of development.

In a two-part study published on December 16 in the journal Endocrinology, a team of researchers led by Susan Nagel at the University of Missouri reported a variety of potent endocrine-disrupting properties in twelve chemicals commonly used in drilling and fracking operations. The team also documented potent endocrine-disrupting activity in ground and surface water supplies collected from heavily drilled areas in Garfield County, Colorado where fracking chemicals are known to have spilled. The levels of chemicals in these samples were sufficient to interfere with the response of human cells to male sex hormones, as well as estrogen. Five samples taken from the Colorado River itself showed estrogenic activity.  The catchment basin for this drilling-dense area, the Colorado provides water to 30 million people.

These results, which are based on validated cell cultures, demonstrate that public health concerns about fracking are well-founded and extend to our hormone systems. The stakes could not be higher. Exposure to EDCs has been variously linked to breast cancer, infertility, birth defects, and learning disabilities. Scientists have identified no safe threshold of exposure for EDCs, especially for pregnant women, infants, and children.

Contact:  Sandra Steingraber, PhD