By Arlene Gregorius

Kim Thoa is a bright and cheerful fourteen-year old girl from the North of Vietnam. She speaks some English, and has a talent for drawing and painting. She also suffers from a very disfiguring skin condition: her face and body are covered in patches of inky-black, scaly skin.

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That's why she's taught at Than Shuan Peace Village, one of several special boarding schools in Vietnam for children with a range of mental and physical disabilities. Why should Thoa's black skin patches put her in a class with pupils who have severe learning difficulties? Because all these children, regardless of the nature of their various conditions, are alleged to be victims of Agent Orange, the herbicide and defoliant sprayed over much of South Vietnam during the war.

But how could the children, none of whom is older than sixteen, possibly be victims of the Vietnam war, which ended in 1975? And how could they be affected by a substance sprayed only up until 1971? We asked the deputy director of the Peace Village, Nguyen Huy Long.

Agent Orange has been linked to mental and physical problems

"Although the war ended long ago", he said, " the children here are still considered victims of the war, because their parents fought in the battlefields in the South, and were affected by Agent Orange." In other words, according to Nguyen Huy Long, Agent Orange caused the veterans to father children with mild or severe birth defects.

The children probably get better medical care here than they would otherwise, and they're not made to feel freaks. But we had a strong feeling that the brighter children here were unlikely to reach their full intellectual potential.

And it also seemed to us that these children were being used for propaganda purposes. Their future appeared to be sacrificed to the greater good of gaining international sympathy, and funding. For, as we found out, there is now a veritable Agent Orange trail, well trodden by foreign journalists, charity workers, and anyone else who shows a serious interest in the matter. All are taken to the same places.

After the Peace Village, our next stop was the 10-80 committee, so-called because it was set up by the Vietnamese government in October 1980 to investigate the effects of Agent Orange on people's health and on the environment. We asked Professor Hoang Dinh Cau, the chairman of the Committee, about their findings.

"What we discovered is that Agent Orange causes diseases in victims' eyes, as well as the lungs, the liver and other organs. But especially, we discovered birth defects in the children of affected people." He then showed us a number of statistical charts. There was one about the number of babies born with birth defects in one of the main hospitals of Ho Chi Minh City (formerly Saigon). It showed that the number of such births rose dramatically after the Vietnam war. Another graph showed that levels of dioxin in mothers' breastmilk were up to seventeen times the maximum safety level.

Banners warn of the dangers of dioxin

Agent Orange is a compound of two herbicides, and the combination of these created a type of dioxin as a by-product. This substance is the most toxic chemical known to mankind. Five parts per trillion are known to kill laboratory animals. No scientist, whether in Vietnam or the West, would dispute that dioxin can cause a whole range of cancers, and some other diseases. But birth defects?

Professor Arnold Schecter of the University of Texas School of Public Health is one of the world's leading experts on the subject. He's made fifteen working trips to Vietnam, two of them this year. He insists that it's extremely unlikely that most of the deformities shown to people in Vietnam are caused by Agent Orange.

The higher levels of dioxin in breast milk only exist in a small number of women in the South, and not in the North, he says, so it's almost impossible that the conditions of the children in the Thanh Shuan Peace Village, for instance, are caused by Agent Orange.

Professor Schecter admits that "Vietnam is the world's worst dioxin incident", and that therefore when quoting Western evidence, one might not be comparing like with like. However he says scientists have learnt enough from other dioxin contaminations - in Italy, Taiwan or Japan - to be sure that the vast majority of birth defects are not caused by Agent Orange.

We took the train south, to Quang Tri province just south of the former DMZ, the "demilitarised zone" on both sides of what was the border between the Communist North and the American-backed South Vietnam during the war. Quang Tri province was one of the most heavily sprayed areas of Vietnam, and where some of the toughest fighting took place.

Khe Sanh, Hamburger Hill, the Ashau Valley, Camp Carol, Con Tien - all these former U.S. marine bases and battlefields were Quang Tri. The U.S. bases repeatedly sprayed their surroundings with Agent Orange to give clear fields of fire in every direction.

We went to a village near Con Tien to meet a local farmer, who has seven children. The three eldest were born whilst the family lived in an area that had not been sprayed, and they were healthy.

This farmer had three healthy, then four disabled children

The disturbing fact was that the four youngest were born here, in Quang Tri province, and they were all both mentally and physically disabled. "When the oldest of the four was born", hed told us, " the doctor said that maybe I was affected by a poisonous chemical. He advised me not to have any more children."

As we walked away from the village, we met another team of journalists. Quang Tri province, too, is a firm fixture on the Agent Orange trail. But could the conditions of the farmer's four youngest children really be caused by dioxins in the soil, and hence the food chain, here?

Professor Arnold Schecter doubts it. To prove it, one would have to test blood samples of the farmer and his family to see if they contain elevated dioxin levels. This is expensive, costing up to US $1,000 per sample. Few laboratories in the world - and none in Vietnam - can do it.

The high cost is only one reason why more research on Agent Orange's legacy has not been done. Both Vietnam and the US are reluctant to fund it. And the reasons for that reluctance are political.

The Vietnamese government isn't united on the issue. Those concerned with public health want more research done, but those dealing with commercial interests don't want any adverse publicity about dioxins which could affect food exports, such as rice, and tourism.

The US attitude is also ambiguous. No-one from the US Embassy in Hanoi or at the State Department in Washington was prepared to speak to us. But it's clear that the US is worried about possible compensation claims from Vietnam.

There are already claims for a billion dollars compensation for Agent Orange damage, from South Korean veterans who fought on the American side during the Vietnam war. So the US too is playing for time.

Also in this edition of Crossing Continents: a visit to the music school in the old imperial capital of Hue, where old ensemble traditions are being revived, and the youngest teacher is 79!