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Web-only Exclusives
November 30, 2000

From Our Correspondent: Hirohito and the War
A conversation with biographer Herbert Bix

From Our Correspondent: A Rough Road Ahead
Bad news for the Philippines - and some others

From Our Correspondent: Making Enemies
Indonesia needs friends. So why is it picking fights?

Asiaweek Time Asia Now Asiaweek story


A persistent problem with pollutants

WHEN BELGIAN AUTHORITIES FINALLY admitted the country's eggs and poultry were tainted with carcinogen dioxins, Asia was quick to act. Health regulators from Bangkok to Taipei imposed a ban on food imports from Europe and ordered a recall of suspect products such as milk formula. Now officials have added reason to be glad they did not procrastinate. The source of contamination - an 80,000-kg batch of fat that a Belgium company sold to feed mills supplying European farms - did not only contain dioxin. There was another class of hazardous chemical present: polychlorinated biphenyls (PCBs).

A chicken taken from a Belgian farm in April had 400 parts per million of PCBs in its fatty tissue. That is 400 times the accepted limit in Holland, say scientists at a Dutch laboratory, the nearest facility that could test for dioxins and related chemicals. (The tainted fat was also found to contain 781 parts per trillion of dioxin - 1,500 times higher than the Dutch safe level.) That was then. But as late as June 11, PCB levels 65 times the German limit were detected in eggs exported to that country. Belgian chicken burgers were similarly contaminated.

How did the toxic chemicals get into the fat? Some suspect that waste industrial oil containing dioxin and PCBs was placed into a container meant for recycled frying fats. PCBs are used in many industries: as heat-exchange liquid in transformers, in paint additives and in making plastics. Dioxin, though, is usually formed as a byproduct in processes such as copper smelting, paper-production and the making of pesticides and chlorine-containing organic chemicals.

Dioxins and PCBs are among a "dirty dozen" dangerous compounds known as persistent organic pollutants. As the name suggests, their effects are particularly pernicious because the chemicals are very stable and stay in the environment for a long time. Dioxin, which is fat soluble, has a "half-life" of seven years in the body: It takes that long to break down half the quantity of the compound. Worse, once absorbed, the chemical is locked into the body's fat tissue (it is only excreted through the placenta and in breast milk).

Brief exposure to high levels of PCBs and dioxins may cause skin lesions and affect the liver (the tolerated daily intake for dioxin is about 1 picogram - one trillionth of a gram - per kg body weight). Over longer periods, the harm is transferred across generations. Babies of women exposed to the chemicals may suffer impaired memory and learning ability. Damage seems to stem from dioxin's interference with crucial biochemical messengers such as the thyroid hormones, which regulate metabolism and help the brain to develop. Untreated, toddlers short of the hormones can become mentally retarded. In moderate cases, the pollutants disrupt youngsters' neurological development. Another effect: behavioral abnormalities such as attention-deficit disorder. In adults, the chemicals may disrupt immune systems and reproductive function. And there's no avoiding increased risks of cancer - to liver, gall bladder and the lymph system.

For health officials in Asia, the next pressing task is disposal of potentially poisoned foods. Burial in landfills is a common choice. But danger may well return in another form if the toxic chemicals leach into the groundwater. A safe food supply requires a clean environment too.

This edition's table of contents | Asiaweek home



U.S. secretary of state says China should be 'tolerant'

Philippine government denies Estrada's claim to presidency

Faith, madness, magic mix at sacred Hindu festival

Land mine explosion kills 11 Sri Lankan soldiers

Japan claims StarLink found in U.S. corn sample

Thai party announces first coalition partner


COVER: President Joseph Estrada gives in to the chanting crowds on the streets of Manila and agrees to make room for his Vice President

THAILAND: Twin teenage warriors turn themselves in to Bangkok officials

CHINA: Despite official vilification, hip Chinese dig Lamaist culture

PHOTO ESSAY: Estrada Calls Snap Election

WEB-ONLY INTERVIEW: Jimmy Lai on feeling lucky -- and why he's committed to the island state


COVER: The DoCoMo generation - Japan's leading mobile phone company goes global

Bandwidth Boom: Racing to wire - how underseas cable systems may yet fall short

TAIWAN: Party intrigues add to Chen Shui-bian's woes

JAPAN: Japan's ruling party crushes a rebel at a cost

SINGAPORE: Singaporeans need to have more babies. But success breeds selfishness

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