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Monday, July 17, 2000

OUR PLANET EARTH

Dioxin found deadly for sure -- and they're pumping it out


First, the good news.

At the end of June, the Environment Agency announced that estimated dioxin emissions in Japan have dropped over 60 percent since 1997. The agency reported that annual emissions were down to between 2,600 grams and 2,800 grams in 1999.

The bad news? Actual total emissions may well be four times that amount, and there is no longer any doubt that dioxins are deadly.

After almost 10 years of reviewing studies on dioxin, the U.S. government last month released a draft report that declares dioxin a definite "human carcinogen." In the report, the U.S. Environmental Protection Agency indicates that dioxins are as much as 10 times more toxic than previously recognized. The report confirmed that dioxins are found across the globe, in our food supply, and in the bodies of people throughout the world.

Dioxins are endocrine disruptors, which means they can act like hormones in the body, interfering with sexual development and causing infertility. They also cause cancer.

The people most at risk from dioxins are those who eat large amounts of dairy and fatty meat products. In addition to other risks they may be exposed to, these individuals face a cancer risk as high as one in 100, depending on their lifestyles.

The problem is, everyone is at risk. "It is likely that part of the general population is at, or near, exposure levels where adverse effects can be anticipated," says the EPA report.

Furthermore, U.S. levels of dioxin are well below those found in Japan. In a story on dioxin in May, Japan Times writer Mick Corliss noted that Japan's air contains 10 times the amount of dioxin found in other industrialized countries.

The U.S. is not the first to admit the dangers of dioxins. In 1998, the World Health Organization dramatically cut their standard for a tolerable daily intake of dioxin, from 10 picograms per day to between 1 and 4 picograms per kilogram of body weight per day (a picogram is a trillionth of a gram). WHO experts warn that "subtle effects occur in the general population in developed countries at background levels of 2 to 6 picograms per kg body weight and day."

The EPA report notes that about 7 percent of daily cancer deaths in the U.S., or 100 out of 1,400, could be due to dioxin. According to the London-based Guardian newspaper, the EPA report concurs with a report released last year by a group of German scientists who concluded that dioxins could be responsible for 12 percent of human cancers in industrialized countries.

Dioxins are not produced deliberately, but rather are "unwanted byproducts of many chemical industrial processes and of all combustion processes," according to a 1999 UNEP Chemicals report. UNEP Chemicals is a division of the United Nations Environment Program. The report, released last May, is titled "Dioxin and Furan Inventories, National and Regional Emissions of PCDD/PCDF."

Using 1995 as a reference year, UNEP determined that total dioxin emissions from 15 of the most developed nations were between 8,300 grams and 36,000 grams annually, with a central estimate of 10,300 grams.

Japan alone generated 5,300 grams in 1998, according to a Ministry of International Trade and Industry emissions inventory. The MITI report also states that municipal solid waste incinerators generated about 80 percent (4,300 grams) of Japan's 1998 dioxin emissions. Based on these figures, UNEP determined that Japan produces almost 40 percent of all airborne dioxins from identified sources worldwide.

After municipal incinerators, the main sources of dioxins in Japan are incinerators that burn organic chloride waste and waste oil, medical waste incinerators, and metal works. Incinerators generate more than 90 percent of Japan's dioxins.

Any time you combine heat, chlorine and organic material, there is a chance of making dioxins. Since Japan incinerates three quarters of its annual municipal solid waste (about 50 million tons), and much of that waste contains polyvinyl chloride plastics used in packaging, it is not surprising that Japan is the leading dioxin producer.

Still, no one knows exactly how much dioxin Japan emits annually. The most recent Environment Agency figures are between 2 and 3 kg, while one citizens' group, Kanto Network to Stop Dioxin Pollution, told Corliss that emissions are closer to 15 or 20 kg per year. In either case the numbers are way too high, and not knowing the exact problem is almost as bad as ignoring it.

Concerned about dangerous dioxin levels in Japan, last year a Tokyo-based consumer group, Seikatsu Club, decided to find out for itself how much dioxin is billowing around us. The group asked members for donations of time and money, and began collecting needles from black pine (kuromatsu) trees.

Evergreen needles absorb dioxin from the air during respiration. Dioxin quickly builds up in the needles and within about four months becomes stable at a level representing dioxin levels in the air. By systematically collecting needles from trees across a particular area on several occasions over time, then testing the needles, it is possible to find the average density of dioxin in the atmosphere in that area.

The survey was done in cooperation with Teiichi Aoyama, Director of the Environmental Research Institute Inc.

Researchers found that if the dioxin density in pine needles is higher than 5 pg-TEQ per gram, atmospheric dioxin in that area may exceed the Environment Agency standard that sets an environmentally safe limit for dioxin at 0.6 pg-TEQ per cu. meter. Finding this correlation made it possible to compare dioxin found in the needles and dioxin in ambient air.

The average dioxin level in Tokyo needles was 3.81 pg-TEQ per gram. The highest levels in the area were found in Tachikawa (6.82), Suginami-ku (5.80), Hoya (5.78), Kiyose (5.60), Hachioji (5.54), the Tama area (5.48) and Nerima-ku (5.14).

The highest overall average for a region was Chiba (4.48) with a high of 8.02. Kanagawa Prefecture averaged 3.06 pg, Hokkaido averaged 0.62, and in Kyushu the average was 1.21, with a high of 5.43 pg in Chikuho, Fukuoka Prefecture.

Those familiar with the controversy over a private incinerator located next to the U.S. Navy's Atsugi Airbase in Kanagawa Prefecture will not be surprised to learn that the highest dioxin levels anywhere were found on the base, about 400 meters from the incinerator: 53 pg-TEQ per gram.

Seikatsu Club is committed to ongoing testing, and hopes the government will begin to supervise waste disposal more strictly, encourage returnables and recyclables, and promote composting of kitchen garbage. The group would also like the business sector to take more responsibility for waste reduction and proper disposal.

Japan estimates that annual dioxin emissions should be at about 600 grams by 2002, but even this figure is unacceptable. As a commentator pointed out, even one dioxin death is inexcusable when the wastes that cause these deaths can be prevented, reduced and managed through recycling and composting.

As things stand now, however, every year hundreds of lives are going to waste.

For more information, see the Web sites at www.jca.apc.org/seikatsu www.eri.co.jp and www.epa.gov/ncea/dioxin.htm E-mail Stephen Hesse at steve@tamacc.chuo-u.ac.jp


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