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Japan
http://www.japantimes.co.jp/news/news6-99/news.html#story1
June 21, 1999
Stricter dioxin standard urged for biggest industrial emitter
The government should drop the maximum tolerable daily intake
of dioxin to 4 picograms per kilogram of body weight, a government
advisory panel said in a report released Monday.
For the first time, coplanar PCBs (polychlorinated biphenyls),
toxic substances similar to dioxin, will also fall under the new
standard. The
recommendations of the joint panel, which is composed of
advisory panels to the Health and Welfare Ministry and the Environment
Agency, are to be presented to the Cabinet for approval
Friday.
Japan emits the most dioxin into the air among the 15
industrialized countries that have compiled national inventories of such
emissions,
according to a recently released study by the United Nations
Environment Program.
According to the study, Japan was emitting nearly 4 kg of
dioxin per year into the air as of 1995 -- mostly from municipal waste
incinerators -- out of a total of 10 kg per year for all 15
countries.
Japan's dioxin emissions were four times that of France, the
biggest emitter of dioxin in Europe. The United States, which came
second in
dioxin emissions, emitted 2.8 kg a year.
The TDI is the amount of dioxin that scientists believe people
can consume daily without suffering adverse health effects. One picogram
is
a trillionth of a gram.
The new 4 picogram figure will lower and also unify the
different figures set by the Health and Welfare Ministry (formerly 10
picograms)
and the Environment Agency (5 picograms). The disparate
figures have often been a source of confusion and criticism.
With the revised figure, the government will effectively
jettison its traditional means of calculating the TDI. Instead, it will
adopt a
calculation embraced by the World Health Organization in May
last year based on animal testing.
The new standard will also coincide with the upper limit of
the WHO's TDI figure, which was revised in May 1998 to call for a
maximum
intake of 4 picograms of dioxin a day with the ultimate goal
of achieving less than 1 picogram. The average Japanese is estimated to
ingest
2.6 picograms per kilogram of body weight per day.
Unlike the WHO, however, the government avoids setting a range
of TDI values in its report, settling instead on the 4 picogram
standard.
While WHO and government figures are based on nearly the same
data, the government panel said WHO data contain minor
miscalculations. It also claimed that while some experiments
have indicated adverse effects, such as lowered sperm count in rats
given
concentrations of dioxin similar to those people encounter in
the environment, these data are "relatively lacking in reliability."
An attempt to replicate a similar study in Japan earlier this
year failed.
The new TDI level will form a foundation for the establishment
of standards regulating the levels of dioxin in the environment. The
Environment Agency is committed to coming up with air
standards for dioxin by December, with an eye to setting soil and water
standards
at a later date.
Officials say the government will review the new standards
following the WHO's TDI review in 2003.
In the report, the panel also notes that more than 90 percent
of dioxin is ingested through food and that dioxin concentrations in
breast
milk has dropped by nearly half since 1973.
The report recommends breast-feeding for infants, although a
Japanese infant being breast-fed ingests an average of 60 picograms of
dioxin a day through such feeding. "Breast-feeding should be
recommended because it has other beneficial effects on infants," the
report
says.
But the new figure was not greeted with enthusiasm on all
fronts. Representatives of the Stop Dioxin Pollution Network visited the
Environment Agency last week appealing to the government to
adopt a stringent standard in line with the WHO.
Members of the organization's Kanto chapter handed out flyers
to people attending Monday's report presentation. They lambasted the
government for failing to adopt a 1 picogram TDI standard and
claimed that data indicating health risks at lower levels were not
reliable.
The group also demanded that the minutes of working group
meetings leading to the 4 picogram standard be made public.
Although the effort to revise the acceptable dioxin intake
level began last year, it was greatly accelerated by the uproar
following a
February media report alleging that high concentrations of
dioxin were found in agricultural products from Tokorozawa, Saitama
Prefecture.
The ensuing frenzy prompted Prime Minister Keizo Obuchi to
establish a Cabinet- level committee to address dioxin policy. The newly
established standard is one result of policy guidelines
released by the group at the end of March.
At Monday's joint advisory committee meeting, Health and
Welfare Ministry officials said the government plans to reevaluate waste
emission standards and look into creating environmental
standards and the possibility of food standards based on the new TDI
figure.
The WHO has recognized that dioxin may already be subtly
affecting people in developed countries and that efforts need to be made
to
minimize exposure to the chemical.
The government is slated to release a study of national
emissions of the chemical within the next few weeks.
Dioxin is an unintentional byproduct of some industrial
practices and waste incineration, especially when chlorine-based
products are
burned at relatively low temperatures.
It has been shown to cause cancer and in recent years has been
implicated as a potent endocrine disrupter.
http://www.mainichi.co.jp/english/news/news01.html
Mainichi Daily News
Tuesday, June 22, 1999
Daily dioxin limit cut to 4 picograms
By Kimio Kamoshita
Mainichi Shimbun
The amount of
dioxins that human
beings may ingest on
a daily basis without
ill effects to their
health should be
reduced to 4
picograms per
kilogram of their
body weight (pg/kg
b.w.), according to
new guidelines
released on Monday
by a government
panel on the toxic
chemicals.
The panel, which is
composed of experts
from the Environment Agency and Ministry of Health and Welfare,
has been working since February to determine the amount of
dioxins
that people may safely ingest in a single day.
The panel's new tolerable daily intake (TDI) conforms to the
upper
limit suggested by the World Health Organization (WHO) in May
1998.
A picogram is one-trillionth of 1 gram.
The Cabinet is expected to approve the new guidelines at a
meeting
to be held on Friday.
Previously, the Health Ministry had set the TDI for dioxins at
10
pg/kg b.w. The agency, on the other hand, has been arguing that
human beings should ingest no more than 5 pg/kg b.w. per day.
The panel, however, did not recommend the adoption of the WHO
numerical TDI target of 1 pg/kg b.w., saying it was
"impossible" to
achieve.
"We recommended a TDI of 4 pg/kg b.w. because it is just about
appropriate and it is also achievable," said Chiharu Toyama of
the
National Institute for Environmental Studies, a panel member.
However, Toyama admits that the panel did come across data
indicating that animals are negatively affected by dioxins at
levels
"below the new TDI level."
The average Japanese ingests 2.6 pg/kg b.w. of dioxins per day.
The
majority of the intake, or some 2.4 picograms, enters the body
in
food.
The panel has indicated that such daily intakes are too close
to the
new TDI guideline, and should therefore be reduced.
According to earlier research by the Health Ministry, seafood
is more
prone to dioxin contamination than other foods.
Based on ministry estimates, a 100-gram slice of fish contains
160
picograms of dioxins on average. If an individual weighing 50
kilograms were to eat just one such slice of fish, he or she
would
ingest the equivalent of 3.2 pg/kg b.w.
As it is normal for most individuals to ingest some 2 pg/kg
b.w. of
dioxins in the form of other foods, consuming a single slice of
fish
would put many people in excess of the new TDI guideline.
Apart from people who frequently eat fish, those most likely to
be
affected by dioxins are breast-fed infants. Some researchers
have
argued that breast-fed babies ingest as much as 60 picograms of
dioxins per day on average. However, the panel insisted that
breast
feeding should nonetheless be encouraged, saying that the
benefits
outweighed the danger posed by dioxins.
The 4 pg/kg b.w. upper limit is based on the results of
research
conducted by the U.S. Environmental Protection Agency on
pregnant
rats. The test animals were given varying amounts of dioxin,
and
scientists noted the effects of exposure to dioxins on their
reproductive organs and immune system.
The report also recommended that the government apply the same
TDI level for another class of highly toxic chemicals -
co-planar
polychlorinated biphenyls (PCBs) - because their ill effects on
animals
are similar to those of dioxins.
Like dioxins, co-planar PCBs can be generated through the
incineration of refuse. Co-planar PCBs are known to contaminate
soil
and can thereby contaminate agricultural products.
WHO is scheduled to review its assessment of the health risks
presented by dioxins and other chemicals in four years' time.
http://www.yomiuri.co.jp/index-e.htm
June 22, 1999
Panel calls for reduction in dioxin TDI standard
Yomiuri Shimbun
A working group of the Health and Welfare Ministry and
the Environment
Agency on Monday submitted a report to their overseeing
committee,
recommending that the human tolerable daily intake (TDI)
of dioxin be set at
no more than four picograms per kilogram of body
weight--in line with the
standard set in May last year by the World Health
Organization (WHO).
TDI is the maximum daily level considered safe for
ingestion during the
course of a lifetime.
The new standard would reduce by more than half the
level of dioxin
currently set as the safe level for daily intake--at 10
picograms per kilogram
of body weight. However, it is still much higher than
the WHO ultimate
dioxin TDI target of less than one picogram.
A picogram is 1-trillionth of a gram.
After its approval by the overseeing committee,
comprising members of the
agency and the ministry, the working group's report will
be forwarded for
approval at Friday's meeting of the Cabinet. Once the
new standard is
endorsed, the government will act to ensure that it is
met nationwide.
A past survey by the ministry and the agency indicated
that the average daily
dioxin intake for Japanese was about 2.6 picograms per
kilogram of body
weight. Compared to the United States and European
countries, a report
based on the survey concluded that the Japanese figure
was within the
tolerable level.
But, unlike the WHO, the working group did not recommend
the
establishment of a future domestic TDI goal. "The (WHO)
data is not
reliable enough to assess the effects on the human
body," the working
group's report said.
In the report, it was also pointed out that the current
average dioxin intake in
the country was "not much lower than the new TDI,"
stressing the necessity
to reduce dioxin emission into the air and to conduct
investigations and
research on the effects on the human body of intake
levels lower than the
TDI.
A comparatively high density of dioxin was detected in
breast milk in Japan,
but the report recommended that breast-feeding be
promoted because,
unlike artificially-produced milk, breast milk contains
colostrum, which
carries antibodies to heighten immune functions.
Japan has standards of dioxins in air (an yearly average
of 0.8 picogram per
cubic meters) and soil (1,000 picograms per gram of soil
in residential
areas), but has no standards for rivers or groundwater.
The government is
considering making stricter standards for air and soil
and setting new
standards for rivers and groundwater.
Small plants emit high levels
Yomiuri Shimbun The Health and Welfare Ministry on
Monday said three
out of 47 small garbage incinerators were found to have
higher levels of
dioxin in their emissions than permitted under ministry
standards for large
incinerators.
The standard for large incinerators is 80 nanograms of
dioxin per cubic
meter of exhaust emission. A nanogram is one-billionth
of a gram.
The official survey was the first of its kind conducted
on small
waste-incineration facilities, for which the government
has yet to set dioxin
emission standards. In light of the results, however,
the ministry said it would
consider applying standards for large facilities to the
smaller plants.
The ministry in fiscal 1998 conducted a random survey on
incinerators with
capacities to process less than 200 kilograms of waste
per hour.
Forty-seven of the country's 80,000 smaller incinerators
put out an average
level of 18 nanograms of dioxin per cubic meter of
exhaust emission. The
highest level recorded was 130 nanograms.
Copyright 1999 The Yomiuri Shimbun
http://www.yomiuri.co.jp/index-e.htm
June 22, 1999
Municipal govts admit burning plastic refuse
Yomiuri Shimbun
Four city administrations in western Tokyo have burned
80 percent of the
plastic they collected from local residents as
incombustible garbage over the
last 30 years, it was learned Monday.
Amid growing concern over dioxin emissions, many local
governments now
encourage residents to separate plastics as
incombustible garbage from
combustible waste. The four administrations are no
exception, and the news
that they have been burning the waste angered residents,
who said they felt
betrayed by their governments.
Dioxins, some of which are highly toxic, are man-made
chemical
compounds. An estimated 80 percent of toxic dioxins are
produced by
burning plastics and other trash that contains chlorine.
The four administrations are Higashikurume, Kiyose, Hoya
and Tanashi, all
located in western Tokyo. These administrations formed
an association, the
Ryusenen-kumiai, to deal with the trash they collect
from local residents.
The administrations acknowledged the practice, but
defended it, saying they
do not have enough space to dispose of the plastics.
The city administrations have urged local residents to
separate plastics from
combustible trash, telling them that those plastics
would be ground into small
pieces at the association's processing site and be
discarded at a disposal site
in Hinodemachi in western Tokyo.
However, it has now become clear that most of those
plastics have been
burned as ordinary combustible waste since 1968, when
Higashikurume
began to request its citizens to separate the trash. The
practice continued
even after Kiyose, the last of the four administrations,
began to separate
garbage in 1972.
According to the association, it burnt 4,600 tons of
plastics in fiscal 1998.
The figure was more or less the same over the past five
years.
The association drafts a basic plan for waste disposal
every 10 years. In the
latest plan, introduced in fiscal 1998, 80 percent of
the plastic collected by
the city would be disposed of by burning.
"We burn plastics because the disposal site (in
Hinodemachi) is losing
capacity to accept new trash and we wanted to improve
the heat efficiency
(by burning plastics) for generating electricity," a
senior official of the
association told The Yomiuri Shimbun.
The official admitted that when plastic materials are
burned in the current
incinerator, it is probable that dioxin can resynthesize
when the filter begins
to catch the dust before processing the smoke.
A survey conducted by the association last September on
garbage
processing facilities found that 360 picograms of dioxin
was detected per
gram of soil in the compound.
A picogram is one trillionth of a gram.
According to Health and Welfare Ministry officials,
municipalities can
process garbage at their own discretion.
The officials also said trust between citizens and
municipalities would be
undermined if municipalities burned plastic materials
after telling citizens they
would not do so.
However, Mayor Michio Inaba of Higashikurume, said that
it was too late
to change the basic way of disposing of plastic
materials.
Thus the association will continue to burn plastic
materials separately from
other garbage.
Yasushi Aoki, director of a local civic environmental
group for processing
garbage, said they were shocked and furious to learn
that the municipal
governments, which had appealed to residents to consider
the dangers of
dioxin, secretly burnt the plastic materials that the
citizens had separated
from other garbage.
Aoki said the municipal governments had betrayed the
citizens.
Copyright 1999 The Yomiuri Shimbun