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ESTIMATES OF SOURCES OF DIOXIN EMISSIONS IN
GRAMS OF TOXIC EQUIVALENT/YEAR, U.S
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EMISSIONS INTO MEDIA
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SOURCE
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EMISSIONS IN GRAMS OF TOXIC EQUIVALENT
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% OF TOTAL
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Air
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Medical Waste Incineration
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5,100
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42%
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Municipal Waste Incineration
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3,000
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25%
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Cement Kilns
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350
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3%
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Industrial Wood Burning
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360
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3%
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Coal Burning
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200
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2%
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Secondary Copper Smelting
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230
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2%
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Iron Sintering
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230
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2%
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Transportation Vehicles
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88
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<1%
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Forest Fires
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86
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<1%
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Hazardous Waste Incineration
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35
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<1%
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Sewage Sludge Incineration
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23
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<1%
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Total Air Emissions
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9,800
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81%
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Water
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Paper and Pulp Industry
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110
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<1%
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Land/Landfill
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Sludge and Incinerator Ash
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2,100
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18%
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Commercial Products
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150
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1%
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Total Land/Landfills
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2,250
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19%
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Total Emissions
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12,160
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100%
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Source: Environmental Protection Agency, Estimating Exposure to
Dioxin-Like Compounds, Vol. 2 (Washington, D.C.: June 1994). Estimates for emissions from coal burning and iron sintering are from the Center for the Biology of
Natural Systems, as reported in Lois Marie Gibbs, Dying from Dioxin (Boston: South End Press, 1995).
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There is growing concern over a group of toxic chemicals that accumulate over time in the food
chain and interfere with the endocrine system -- the set of glands and the hormones they produce -- and therefore impact reproduction, growth, and fetal development. Some of these
chemicals may "mimic" natural hormones like estrogen and testosterone, upsetting normal reproductive and developmental processes. Others may block the effects of a hormone or stimulate
the overproduction of hormones. Nonetheless, studies are still being conducted on these chemicals to determine if they indeed are endocrine disruptors and what
long-term health effects they have.
The real-world effects of some of these chemicals is well documented if not well understood. The pesticide
DDT -- which especially affected the eagle and its ability to procreate -- and the electric-transformer lubricant PCBs are the most famous of these chemicals and were banned
in 1972 and 1979, respectively. Today, however, chemicals like dioxin and furans are considered by toxicologists to be as or more dangerous. Dioxin is the common
name for a family of 75 chemicals that are the unintended by-products of industrial processes involving chlorine. For example, in the paper pulp industry, dioxin forms when
chlorine reacts with lignin, the "glue" that holds the wood of the trees together.
Dioxin also forms in processes that burn chlorine with organic matter, such as can occur when cement kilns or
incinerators burn hazardous wastes.* Furans are closely related compounds. While dioxin and its possible harmful
affects have been documented since the 1940s, not until the 1970s did dioxin become a national controversy. The
controversy arose when Vietnam veterans who had been exposed to "Agent Orange," a herbicide contaminated with
dioxin used to destroy rice fields during the war, began to experience a variety of health problems, including
reproductive problems and cancer. Other well-known incidents involving dioxin include the evacuation of a New York
town in 1978 because of the presence of dioxin in Love Canal, and the evacuation of Times Beach, Missouri, in 1983
after years of spraying of dioxin-laced waste oil to control dust had led to serious health problems.* In wildlife,
evidence of dioxin's dangerous effects include the poisoning of fish and the deformation of birds; twisted beaks and
reproductive inability occurred among fish-eating birds in the Great Lakes near pesticide and pulp- and paper-industry plants.*
Documented effects of dioxins and dioxinlike substances include:
- Cancer in wildlife and evidence of cancer in humans;
- Congenital anomalies;
- Weakening of the immune system;
- Liver defects;
- Reproductive and hormonal irregularities;
- Persistence in the environment; and
- Bioaccumulation.
Air emissions of dioxin are of particular concern because the dioxin particles bind to other particles such as incinerator
ash and can then travel long distances, often covering more than 1,000 miles.* Eventually, they settle to the ground or
are washed out by rain. Once in the soil, they can move rapidly through the food chain and are of particular concern
when they accumulate in soil on dairy and beef farms, the main route of human exposure. Dioxin air emissions come
from hazardous waste incinerators, municipal incinerators, medical incinerators, cement plants, wood and coal burning, forest fires, and copper smelting and refining, among other sources.* Water emissions of dioxin are mainly the result
of wastewater discharges from the pulp and paper industry, while land emissions are the result of sludge from these plants and incinerator ash being deposited in quarries and landfills.
Only North Carolina facilities reported releasing more dioxin and dioxin-like substances to the atmosphere than Texas
facilities in 2001. In 2001, Texas facilities -- including utilities, hazardous waste treatment facilities, refineries and
cement plants -- reported releasing 336.8 grams of these substances to the atmosphere. Overall, more than 28,400
grams of dioxin and related substances was released on or off-site, trailing only Delaware.*
In September 1994 the EPA released its second reassessment of dioxins and furans, their sources, and their human
and environmental impacts. This reassessment and other studies have led to the development of new air emission
standards for municipal- and medical-waste incinerators, hazardous waste incinerators and cement plants which burn
hazardous wastes. Many of the cement kilns and medical-waste incinerators will have to comply with these new
standards this year, in 2003. Similarly, the EPA, under the Hazardous Air Pollutant provisions of the Clean Air Act, is
developing new regulations for the sources of mercury, which has a number of serious health impacts, including
possible endocrine disruption. In addition, under the 1996 Food Quality Protection Act and the Safe Drinking Water Act,
the EPA must present a screening and testing program to determine which of the estimated 75,000 pesticides and chemicals currently approved need to be screened for endocrine disruption.
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