Banned Pesticides Linked to Endometriosis

Endometriosis was associated with pesticide exposure among women

/ Author:  / Reviewed by: Chris Galloway, M.D. Beth Bolt, RPh

(RxWiki News) Our environment can affect our bodies in many ways. Even chemicals that were banned decades ago might be affecting some women's health today.

A new study found that endometriosis in women was associated with some chemicals previously used in pesticides.

Endometriosis causes cells that form the lining of the uterus to grow into other areas such as the ovaries and intestines. This outgrowth may cause severe cramps, bleeding and infertility.

This new study showed that pesticides which have been banned in the past, such as organochlorine-based pesticides, can still be found in womens’ blood samples.

The researchers found that the highest concentrations of two types of organochlorine-based pesticides — beta-hexachlorocyclohexane (β-HCH) and mirex — were linked to endometriosis risk.

"Thoroughly wash your food to avoid pesticide consumption."

This study, which looked at the link between endometriosis and pesticides, was conducted by Kristen Upson, PhD, from the School of Public Health at the University of Washington and the Division of Public Health Sciences at Fred Hutchinson Cancer Research Center in Seattle, Washington, and colleagues.

According to Victoria Holt, PhD, MPH, and another author of the study, “Endometriosis is a serious condition that can adversely affect the quality of a woman’s life, yet we still do not have a clear understanding of why endometriosis develops in some women but not in others. Our study provides another piece of the puzzle.”

The researchers analyzed data from 786 women between 18 and 49 years old who were members of the Group Health Cooperative, a healthcare system in the State of Washington.

Of these women, 248 were diagnosed with endometriosis sometime between 1996 and 2001, and the remaining 538 women didn’t have any history of endometriosis (control group).

The researchers measured the concentrations of 11 organochlorine pesticides in blood samples from the participants.

The 11 organochlorine pesticides examined in this study included: β-HCH, gamma-hexachlorocyclohexane (γ-HCH), heptachlor epoxide, oxychlordane, trans-nonachlor, dieldrin, hexachlorobenzene, two types of dichlorodiphenyltrichloroethane (p,p’-DDT, o,p’-DDT), dichlorodiphenyldichloroethylene (p,p’-DDE) and mirex.

“We found it interesting that despite organochlorine pesticides being restricted in use or banned in the US for the past several decades, these chemicals were detectable in the blood samples,” Dr. Upson said.

The researchers explored whether there was a link between endometriosis and a high concentration of any of the 11 organochlorine pesticides measured in the blood samples. They found that two of the pesticides may increase risk for endometriosis.

They reported that a woman with an elevated concentration of β-HCH had about 1.7 times higher odds of having endometriosis and 2.5 times higher odds of ovarian-specific endometriosis compared to someone with low traces.

Additionally, the odds of endometriosis in a woman with elevated concentration of mirex in the blood were about 1.5 times higher than someone without mirex traces in the blood.

While β-HCH was found in 90 percent of the participants' blood samples, mirex was only found in 38 percent. The authors noted that endometriosis risk due to mirex exposure may be more relevant to other populations which have been exposed to higher concentrations of mirex, such as those who consume fish from the Great Lakes and Arctic regions.

This study accounted for the potential influence of demographics (age, race/ethnicity and level of education) and other factors (date of diagnosis, fat content in the blood, smoking and alcohol intake).

Based on these odds, the researchers concluded that exposure to β-HCH and mirex might be associated with endometriosis risk. However, there was not a clear, direct link between each of the other organochlorine pesticides and endometriosis.

According to Dr. Upson, “The take-home message from our study is that persistent environmental chemicals, even those used in the past, may affect the health of the current generation of reproductive-age women with regard to a hormonally driven disease.”

She continued, “We hope our findings will help inform current global policymaking to reduce or eliminate their use.”

This study was published on November 5 in the journal Environmental Health Perspectives. The authors had no disclosures to make.

Review Date: 
November 3, 2013
Last Updated:
November 4, 2013