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Dioxin
Emissions Fall As Technologies, Controls Improve
A new study by the National
Institute of Occupational Safety and Health (NIOSH), as reported
in the Washington Post, found that "most people typically are not
being currently exposed to dangerous levels of dioxin and that cancer
appears to result only among those who had extremely high and long-term
exposure to the chemical 15 to 20 years ago." The NIOSH study cited
the International Agency for Research on Cancer (IARC) finding that
the level of dioxin in human tissue has declined 75 percent over
the last 25 years. The NIOSH study said that increased cancer risk
was found among chemical workers exposed to 100 to 1,000 times the
background level of dioxin in the environment. A 60 percent increase
in cancer deaths was seen in those workers only with the highest
exposure rate.
Dioxin is an unwanted
toxic byproduct of industrial production and natural processes like
forest fires. Dioxin is created when the common elements carbon,
oxygen, hydrogen and chlorine are heated together at temperatures
insufficient to prevent its formation.
Dioxin is known as a
"persistent, bioaccumulative and toxic" (pbt) substance because
it persists in the environment for long periods and is potentially
harmful in large enough doses over long periods. ARCC supports government
policies and industrial practices designed to continuously reduce
dioxin and other industrial emissions.
According to the Environmental
Protection Agency (EPA), dioxin emissions from known sources have
fallen 75 percent since 1987. Today, dioxin levels are back to where
they were before World War II and the rise of the modern chemical
industry. New incineration technologies that burn waste at precisely
controlled temperatures are rapidly eliminating dioxin emissions.
New chlorine chemistry technology virtually eliminates dioxin discharges
from U.S. pulp and paper mills.
The good news is: new
policies and practices are succeeding. Dioxin emissions are falling
without undue impact on employment and investment in the major industries
that use the products of chlorine chemistry. The U.S. chlorine production
industry is an insignificant contributor of dioxin, releasing 6
grams out of a total of 3,000 grams emitted annually. Basic industries
that use chlorine in their processes are more significant emitters.
EPA Will Release New
Study on Dioxin
The EPA is scheduled
to soon release its "Dioxin Reassessment" which will collect and
analyze the most current information about dioxin and its impact.
There is controversy concerning whether current dioxin levels in
the environment are capable of causing harm.
Dioxin levels in human
milk and fat tissue have shown a major decline since the 1980s.
According to the American Chemical Society, people took in an average
of 10 trillionths of a gram per kilogram of body weight daily in
the late 1980s. Today, that number has fallen to between one and
three trillionths. Dioxin levels will continue to decline as strict
new EPA standards for municipal, hazardous and medical waste incinerators,
as well as for pulp and paper mills, take effect. The new standards
will reduce dioxin emissions from these sources by another 90 percent.
However, dioxin emissions
from "uncontrolled" sources such as diesel vehicles, residential
wood burning and landfill fires may be greater than emissions from
"controlled" sources like incinerators. EPA is beginning to quantify
these emissions.
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