thedrifter
04-17-03, 07:56 AM
More Agent Orange Sprayed in Vietnam Than Thought
Wed Apr 16, 5:31 PM ET
By Keith Mulvihill
NEW YORK (Reuters Health) - The U.S. military sprayed roughly 1.8 million more gallons of dioxin-containing herbicides like Agent Orange in Vietnam then had been previously estimated, scientists announced Wednesday
What's more, a new look at military data indicates that millions of Vietnamese people were likely to have been sprayed directly with the chemicals and that many U.S. military personnel were also sprayed or came in contact with herbicides in recently sprayed areas.
The new study was conducted under contract to the National Academy of Sciences (news - web sites) in order to develop a method for evaluating the extent of exposure of Vietnam veterans to herbicides, the study's lead author Dr. Jeanne Mager Stellman explained in an interview with Reuters Health.
"The U.S. and Hanoi signed an agreement last year to cooperate on research and remediation of environmental damage (that resulted from the spraying)," said Stellman. "Our data will help to guide that research to the most exposed people and places."
Millions of gallons of Agent Orange, named after the striped orange barrels used to transport it, and other herbicides were sprayed over Vietnam by the U.S. military beginning in 1961. The aim was to clear forests and damage enemy food crops during the Vietnam War. Seven years after the program began, studies linked the chemical to birth defects and the use of all defoliants was stopped.
Dioxin, which has been fingered as the toxic component in Agent Orange, caused the 1983 evacuation of the town of Times Beach, Missouri, and the 1978 evacuation of the Love Canal site in Niagara Falls, New York.
Dioxin builds up in living tissue over time, so even small exposures can accumulate to dangerous levels.
While many reports about the use of the defoliants have been published during the decades following the Vietnam War, which ended in 1975, many aspects of their use remains controversial -- including how much of the defoliants were actually used and where they were sprayed.
Now, Stellman, of Columbia University in New York City, and colleagues have published revised estimates after combing through a more complete set of original military spraying records. Her team's finding are published in the journal Nature.
"We are the first people to look at a lot of the military records, like Air Force operational folders, that had been 'secret' during the war and have pretty much been in the National Archives for years without having been looked at critically," said Stellman.
The re-estimated volume of herbicides sprayed between 1961 and 1971 is 7,131,907 liters (approximately 1.8 million gallons) more than an "uncorrected" estimate published in 1974 and 9.4 million more liters than a 1974 "corrected" inventory, the authors report in their study.
"We've found much more dioxin contamination than had been previously estimated and we also have found the specific targets that the Air Force (sprayed in) Vietnam," Stellman told Reuters Health.
The study "gives new figures about how much dioxin was dispersed and clarifies where the 'hotspots' are likely to be," added Stellman.
The investigators report that 3,181 villages were sprayed directly with herbicides. "At least 2.1 million but perhaps as many as 4.8 million people would have been present during the spraying," they write.
Evidence also indicates that some people were sprayed with herbicide at levels an order of magnitude greater than levels used in the U.S. for similar purposes.
What's more, Stellman emphasized that that even after all these years, health experts still don't know what effects the veterans may have suffered.
"We don't even have a good count of how many of them served in sprayed areas," she added. "That's why our particular studies were undertaken."
And, Vietnamese people also benefit from the investigation because interested scientists can zero in on the "hot spots" and see what sort of remediation is needed, explained Stellman.
"(The Vietnamese) may also learn more about the health effects (of the herbicides)," added Stellman, who noted that "there are a number of researchers around the world interested in working with them on these problems and we've drawn an exposure roadmap for them."
In the past, health experts have often said that little could be done for people potentially exposed to Agent Orange without an evaluation of how and where the spraying was conducted, explained Stellman.
"Well, now we have the (spraying inventory), we know where the hot spots are and we've developed an-easy-to-use computer system for researchers to assess exposure opportunity.
"We should be designing and undertaking definitive health studies as soon as possible," Stellman concluded.
SOURCE: Nature 2003;422:681-687.
Sempers,
Roger
Wed Apr 16, 5:31 PM ET
By Keith Mulvihill
NEW YORK (Reuters Health) - The U.S. military sprayed roughly 1.8 million more gallons of dioxin-containing herbicides like Agent Orange in Vietnam then had been previously estimated, scientists announced Wednesday
What's more, a new look at military data indicates that millions of Vietnamese people were likely to have been sprayed directly with the chemicals and that many U.S. military personnel were also sprayed or came in contact with herbicides in recently sprayed areas.
The new study was conducted under contract to the National Academy of Sciences (news - web sites) in order to develop a method for evaluating the extent of exposure of Vietnam veterans to herbicides, the study's lead author Dr. Jeanne Mager Stellman explained in an interview with Reuters Health.
"The U.S. and Hanoi signed an agreement last year to cooperate on research and remediation of environmental damage (that resulted from the spraying)," said Stellman. "Our data will help to guide that research to the most exposed people and places."
Millions of gallons of Agent Orange, named after the striped orange barrels used to transport it, and other herbicides were sprayed over Vietnam by the U.S. military beginning in 1961. The aim was to clear forests and damage enemy food crops during the Vietnam War. Seven years after the program began, studies linked the chemical to birth defects and the use of all defoliants was stopped.
Dioxin, which has been fingered as the toxic component in Agent Orange, caused the 1983 evacuation of the town of Times Beach, Missouri, and the 1978 evacuation of the Love Canal site in Niagara Falls, New York.
Dioxin builds up in living tissue over time, so even small exposures can accumulate to dangerous levels.
While many reports about the use of the defoliants have been published during the decades following the Vietnam War, which ended in 1975, many aspects of their use remains controversial -- including how much of the defoliants were actually used and where they were sprayed.
Now, Stellman, of Columbia University in New York City, and colleagues have published revised estimates after combing through a more complete set of original military spraying records. Her team's finding are published in the journal Nature.
"We are the first people to look at a lot of the military records, like Air Force operational folders, that had been 'secret' during the war and have pretty much been in the National Archives for years without having been looked at critically," said Stellman.
The re-estimated volume of herbicides sprayed between 1961 and 1971 is 7,131,907 liters (approximately 1.8 million gallons) more than an "uncorrected" estimate published in 1974 and 9.4 million more liters than a 1974 "corrected" inventory, the authors report in their study.
"We've found much more dioxin contamination than had been previously estimated and we also have found the specific targets that the Air Force (sprayed in) Vietnam," Stellman told Reuters Health.
The study "gives new figures about how much dioxin was dispersed and clarifies where the 'hotspots' are likely to be," added Stellman.
The investigators report that 3,181 villages were sprayed directly with herbicides. "At least 2.1 million but perhaps as many as 4.8 million people would have been present during the spraying," they write.
Evidence also indicates that some people were sprayed with herbicide at levels an order of magnitude greater than levels used in the U.S. for similar purposes.
What's more, Stellman emphasized that that even after all these years, health experts still don't know what effects the veterans may have suffered.
"We don't even have a good count of how many of them served in sprayed areas," she added. "That's why our particular studies were undertaken."
And, Vietnamese people also benefit from the investigation because interested scientists can zero in on the "hot spots" and see what sort of remediation is needed, explained Stellman.
"(The Vietnamese) may also learn more about the health effects (of the herbicides)," added Stellman, who noted that "there are a number of researchers around the world interested in working with them on these problems and we've drawn an exposure roadmap for them."
In the past, health experts have often said that little could be done for people potentially exposed to Agent Orange without an evaluation of how and where the spraying was conducted, explained Stellman.
"Well, now we have the (spraying inventory), we know where the hot spots are and we've developed an-easy-to-use computer system for researchers to assess exposure opportunity.
"We should be designing and undertaking definitive health studies as soon as possible," Stellman concluded.
SOURCE: Nature 2003;422:681-687.
Sempers,
Roger