US scientists question Vietnam dioxin studies
Date: 06-Mar-02
Country: VIETNAM
Author: David Brunnstrom
While not questioning that dioxin - which contaminated Agent Orange - was capable of harming health, the scientists from the U.S. Environmental Protection Agency (EPA) and National Institute of Environmental Health Sciences (NIEHS) said Vietnam's research needed to be reviewed and replicated.
"If you are talking about something as complicated as birth defects or cancer or other chronic diseases, especially a multi-generational potential disease, that is going to take years and years and years," said Christopher Portier of NIEHS.
"Findings have been presented (by Vietnam) that suggested some of those conclusions have been drawn and we are trying to understand better the basis for those. We need to look more closely at the information that underlies those conclusions."
Portier spoke during a briefing after the second day of a landmark scientific conference in Hanoi on Agent Orange and dioxin, involving Vietnamese and U.S. government scientists as well as international experts.
Portier, the director of the NIEHS's environmental toxicology programme, is the chairman of the meeting.
William Farland, from the EPA's research office, said experience elsewhere showed the longer the time since exposure to dioxin, the harder it became to study the effects.
"As the levels get lower and lower, our ability to determine who was exposed and who was not exposed becomes more difficult," he said.
MILLIONS OF GALLONS SPRAYED ON VIETNAM
U.S. forces dumped millions of gallons of Agent Orange on Vietnam during the war that ended in 1975 to deny communist soldiers jungle cover. Spraying was halted in 1971 after it was discovered it contained the most dangerous form of dioxin, TCDD, and caused cancer in rats.
The issue is a tricky one for the United States, which has faced compensation demands from both Hanoi and U.S. veterans for exposure to Agent Orange.
Farland said there was data that showed researchers needed to be looking for current exposure to dioxin which might be from long-lived chemicals in so-called Agent Orange "hotspots".
He said the United States was funding a pilot project experimenting with a cheaper type of testing for dioxin at one such hotspot in Danang, a major U.S. base area during the war.
He said there was general understanding between Vietnam and the United States and in the conference of the importance of locating such hotspots, and findings from these would be helpful in the study of dioxin exposure elsewhere in the world.
Washington was providing $400,000 for the pilot in Danang and offering cleanup advice, but there had been no talk of the United States participating in such a cleanup, he said.
While U.S. veterans have received some compensation for diseases "associated" with dioxin exposure, U.S. officials say this was a political decision and government scientists do not recognise a causal effect.
The current conference is aimed at establishing what is already known about the effects of Agent Orange and establishing future research priorities. A previous meeting in Singapore in late 2000 stalled over Vietnamese compensation demands.
Farland said one of the long-term aims was "to bring (Vietnamese) scientists to a point" at which they could compete for research funding on the issue.
"The truth lies somewhere between that dioxin causes everything and dioxin doesn't cause anything," he said. "Where it is we don't know. The more research we do around the world, the closer we'll get to finding that ground."
Senior officials of Vietnam Veterans of America, which has fought for years for compensation for U.S. veterans, said earlier they felt Washington, and Agent Orange manufacturers Dow Chemical Co and Monsanto Co, had a moral duty to compensate Vietnamese who have suffered from exposure.