Endometriosis affects about 5 million people in the United States and about 10 percent to 15 percent of women globally. Although scientists are not sure about what causes endometriosis and why it affects some people and not others, research indicates that genetics and environmental risk factors have been linked to the condition.

Of the environmental factors being investigated, much of the focus has centered on dioxin exposure and its potential role in the development of severe endometriosis. Therefore, it’s important to understand what dioxin is and how it may affect the condition.

What Is Considered Severe Endometriosis?

The severity of endometriosis is classified into four stages — stage 1 is mild and stage 4 is severe. This classification system, created by the American Society of Reproductive Medicine, is based on the presence of endometrial-like tissue (lesions) found outside of the uterine wall. The location, depth, and quantity of the lesions, the presence of adhesions (scar tissue), potential blockage of the fallopian tubes, and the involvement of pelvic structures are all factors considered in determining the stages. These stages, however, do not necessarily correspond to pain levels, symptoms, or infertility risk.

What Is Dioxin?

Dioxin is a general term that refers to a family of chemically similar substances that pollute the environment, which typically fall into three categories:

• Polychlorinated dibenzofurans (PCDFs)
• Polychlorinated dibenzo para dioxins (PCDDs)
• Dioxin-like PCBs (polychlorinated biphenyl)

These chemicals are also known as persistent organic pollutants. They remain active in the environment for a long time before breaking down and spread easily through the soil, water, and air. These pollutants accumulate in humans and animals with increasingly higher dioxin concentrations at the higher end of the food chain. These substances can cause cancer, damage the immune and reproductive systems, interfere with hormones, and affect developing fetuses.

There are more than 400 dioxin and dioxin-like compounds, 30 of which have been identified by the World Health Organization as significantly toxic to humans and wildlife. Out of those 30 dioxins, 2,3,7,8- tetrachlorodibenzo para dioxin (TCDD) is considered the most harmful.

Where Does Dioxin Come From?

Dioxin can come from naturally occurring sources like forest fires and volcano eruptions, but the majority of dioxins exist as unintentional side effects of human incineration activity like burning medical waste and city trash. Dioxin-like PCBs are human-made chemicals, created for industrial and electrical use.

How Are People Exposed to Dioxin?

Because dioxin is found in our air, soil, and water, exposure can come from multiple sources. The amount of dioxin in the air was greatly reduced when regulations were passed in 1987 to control how much was being released. Currently, the greatest exposure comes from the food people eat — mainly meat, fish, poultry, and dairy products. Dixon is stored in the fat cells of animals, as well as in the fat that occurs in milk, eggs, butter, and other animal products.

Does Dioxin Raise the Risk of Severe Endometriosis?

Dioxins can interrupt the communication of hormones from the endocrine system to other parts of the body. Because dioxins and dioxin-like chemicals can be similar to estrogen and estradiol (hormones involved in the menstrual cycle), it has been suggested that they can influence the risk of endometrial-like tissue growing outside of the uterus.

One research study found that animals that were consistently exposed to TCDD over four years were likely to develop endometriosis. Two different doses of TCDD were given to separate groups of animals, and the researchers found that 71 percent of the higher-dosage group developed moderate to severe endometriosis. Only 43 percent of the lower-dosage group developed the same disease and progression stage. Because of those findings, the study authors concluded that the severity of the endometriosis appeared to be directly connected with the level of dioxin exposure.

A subsequent scientific literature review noted that the theory of dioxin’s link to endometriosis was supported by animal-based evidence. This conclusion gained further support from a 2005 human-based study that reported an association between dioxin-like chemicals PCDD/PCDF and PCB and endometriosis.

In a 2010 study, researchers found that individuals who had a higher concentration of dioxin-like chemical levels in their blood plasma also had a higher risk of developing moderate to severe endometriosis.

To date, there is no direct, conclusive evidence confirming a link between dioxins and severe endometriosis, but researchers continue to investigate the possibility.

Will Reducing Dioxin Exposure Lessen Endometriosis Symptoms?

Reducing contact with toxic chemicals, in general, is a good idea. But does it help with endometriosis symptoms?

Members of MyEndometriosisTeam often report that dietary and lifestyle changes do make a difference in some cases. Some mentioned they started reducing dioxin exposure by eliminating certain foods which, in turn, helped them feel better. One member wrote, “These are the diet changes that can be made to help better manage the day-to-day symptoms: no gluten, dairy, sugar, or grains. Limit your dioxin exposure from meat. This will make a huge difference in how you are feeling.”

The National Institute of Environmental Health Sciences also suggests reducing dioxin exposure through food by consuming fat-free or low-fat versions of dairy products, removing the skin from poultry and fish, and checking local fishing advisories when fishing to be aware of potential contamination of local waterways.

Another MyEndometriosisTeam member recommended a lifestyle change by removing household chemicals to help manage symptoms. “Go totally chemical-free in your home to lessen the growth potential of your endo and dioxin exposure,” she wrote.

Although science has yet to conclusively prove beyond a doubt the connection between dioxin and severe endometriosis, reducing your exposure to these chemicals may be a prudent way to care for your overall health.

Talk With Others Who Understand

MyEndometriosisTeam is the social network for people with endometriosis. On MyEndometriosisTeam, more than 122,000 members come together to ask questions, give advice, and share their stories with others who understand life with endometriosis.

Are you living with endometriosis and searching for information on its connection to dioxin? Share your experience in the comments below, or start a conversation by posting on your Activities page.