Lois Marie Gibbs Executive Director, CCHW

Dioxin -- What's the Problem?

The EPA's draft "reassessment" of the health effects of dioxin estimates that the lifetime risk of getting cancer from dioxin exposure is between one in 1,000 and one in 10,000. Dioxin is also linked to severe reproductive and developmental effects. Dioxin exposure can damage the immune system, leading to increased susceptibility to infectious diseases, and can disrupt the function of regulatory hormones. Infertility, birth defects, impaired child development, diabetes, and thyroid changes are linked to dioxin exposure.

What is dioxin?

Dioxin is not the desired result of any one process, but an unwanted by-product of many chemical, manufacturing, and combustion processes. Any use of chlorine in industrial processes, including incineration, results in dioxin formation.

Where does dioxin come from?

Incinerators -- 95% of 50%

Dioxin is generated by the chlorine content in the waste stream burned in medical and garbage incinerators. Chlorine is present in various plastics, mostly PVCs. When these plastics are burned, chlorine is released, and quickly reacts with available phenol compounds to form dioxin. The phenol compounds are present in wood and paper products. Dioxins are released to the air, end up in the bottom ash, and in the fly ash captured by pollution control equipment.

When chemicals such as PCBs, chlorinated benzenes and chlorinated phenols are burned in hazardous waste incinerators, chlorine combines with available phenol compounds to form dioxin.

The Missing 50%

Although EPA identified chemical manufacturing/ processing and industrial/municipal processes as major sources of dioxin emissions, they had no data to measure how much dioxin is released from these sources. EPA acknowledged that the "agency lacks sufficient information about emissions from known sources" (emphasis added) and has asked industry to "call-in" with information on their dioxin emissions. Forest fires and vehicle exhaust are on the list, but known dioxin sources such as Dow Chemical in Midland, Michigan, Vertac in Jacksonville, Arkansas, and Monsanto in St. Louis, Missouri are omitted.

The Missing Chemical Industry

A major but unmeasured source of dioxin is the chemical industry -- in processes that use chlorine in the production of pesticides, pharmaceuticals, cosmetics, detergents, solvents, and dyes. Herbicides such as agent orange and 2,4-D are made by adding chlorine to phenoxy compounds. Dioxin is formed as a by-product and ends up in the formulated end-product, such as the herbicide Agent Orange or pure PVC polymer, as well as in the process waste streams.

The Unmeasured Pulp and Paper Industry

Another major source of dioxin emissions are pulp and paper mills. Dioxin is formed in the pulp and paper industry when chlorine or chlorine dioxide is used to bleach pulp and paper. Naturally occurring phenol compounds found in wood pulp react with chlorine to form dioxin. This results in dioxin in paper products, paper mill sludge, and in the wastes from these plants.

How Are People Exposed to Dioxin?

Dioxin, like DDT, does not break down easily in the environment. Instead, it bioaccumulates. This means that the body accumulates any dioxin to which you are exposed. Over time, continual low level exposures will "build up" until subtle adverse health effects begin to occur.

Until the EPA report, most people thought they would be exposed to dioxin only if they lived near an incinerator, a contaminated site, a pulp and paper mill or other direct source. Now we know this is not true.

According to EPA, 90% of human exposure occurs through diet, with foods from animals being the predominant pathway. Animals are exposed primarily from dioxin emissions that settle onto soil, water and plant surfaces. Soil deposits enter the food chain by ingestion by grazing animals. People then ingest dioxin through the meat, dairy products, fish and eggs they consume. A recent study by Dr. Arnold Schecter of the State University of New York at Binghampton found dioxin in many food products purchased in an upstate New York supermarket. Schecter estimated that the average daily intake of dioxin is "at least 50 times greater than what EPA estimates is a virtually safe dose of dioxin."

Who is likely to have the highest dioxin levels in their bodies? People that eat more than two inland fish meals a month. People who live near a dioxin source or eat food produced near a dioxin source. Children. Breast fed babies. Anyone who eats a lot of meat, dairy products, or fish. Dioxin is so pervasive that limiting further exposure of the American people cannot be accomplished through lifestyle or dietary changes. The only sensible way to limit further exposure is to shut down the sources of dioxin contamination.

How does dioxin damage us?

The EPA report is full of new information on dioxin including information on how dioxin and dioxin-like chemicals (PCBs, furans) damage the body. Scientists have identified a series of steps that are necessary for most if not all of the observed effects of dioxin and related compounds. Once dioxin is in the body, the molecules of dioxin (the more dioxin you are exposed to the more dioxin molecules present in the body) "attach" to specific receptor "sites" in cell tissue much like a ship pulling into a loading dock at a pier. This site is normally used by hormones and enzymes to regulate certain activities in the body. When dioxins and dioxin-like chemicals occupy this site instead of hormones and enzymes, select normal cell functions cannot be carried out. Hormone activity, developmental/reproductive and immune functions are especially vulnerable to disruption of receptor site activity.

We're Almost Full

One of the most striking findings of the report is the significance of what past dioxin exposures may mean for public health. The report identifies levels of dioxin in the human body referred to as the "body burden." According to EPA, some adverse effects of dioxins occur at levels slightly above average body burden levels currently found in the population and that "as body burdens increase within and above this range, the probability and severity as well as the spectrum of human non-cancer effects most likely will increase."

How Do We Stop Dioxin Exposure?

No amount of additional exposure is safe. So what do we do to stop dioxin exposure? Unlike some other societal problems, we know what it would take to stop emitting dioxin.

At the 2nd Citizens' Conference on Dioxin held in St. Louis, MO in July, 1994 activists created two demands:

1) An immediate halt to the incineration of municipal, hazardous, medical, military and radioactive waste, and any such wastes incinerated in cement and or aggregate kilns, or other devices; and

2) An immediate commencement of a phase-out of the industrial production and use of chlorinated organic compounds (including plastic, PVC).

Greenpeace has called for a national strategy for zero dioxin that would include these actions: