Findings point new path for dealing with Vietnam War’s poisonous legacy
When a small Canadian environmental firm started collecting soil samples on a former U.S. air base in a remote Vietnamese valley, Thomas Boivin and other scientists were skeptical that they would find evidence proving herbicides used there by the American military decades ago still posed a health threat.
But results showed that levels of the cancer-causing poison dioxin were far greater than guidelines set by the U.S. Environmental Protection Agency for residential areas.
That’s when Boivin, now president of the firm, says he had his “eureka moment.” Vancouver-based Hatfield Consultants Ltd. began tracing the toxin through the food chain, from the soil and sediment of nearby ponds to the fat of ducks and fish to the blood and breast milk of villagers living on the contaminated site.
The breast milk of one woman in the study contained dioxin levels six times higher than what the World Health Organization deems safe. She also had a 2-year-old child with spina bifida, one of the birth defects for which the U.S. Department of Veterans Affairs compensates the children of U.S. veterans.
Since then, Hatfield and Vietnamese scientists have taken samples from nearly 3,000 former U.S. military installations scattered throughout former South Vietnam and have identified 28 “hot spots,” including three highly contaminated sites around populated areas in Da Nang, Bien Hoa and Phu Cat.
Their findings offered a way to recast the legacy in Vietnam of Agent Orange and related defoliants as a solvable, though urgent, issue. Instead of a messy controversy over birth defects and other complex health issues, the discovery of persistent contamination focused attention on a measurable, present-day problem that could be addressed.
Yet since the first Hatfield study was published in 2000, the U.S. government has done little to help clean up the sites it contaminated during the Vietnam War, providing just $6 million to tackle both the serious health issues related to the contamination and the significant environmental damage caused by the defoliants.
Boivin and others who have worked on the issue say that since the first studies came out, there has been more cooperation between the U.S. and Vietnam. Hatfield started working in Vietnam pro bono in hopes of landing Canadian government subsidies, but the firm later became committed to studying the problem, donating hundreds of hours and resources.
“During the past few years in particular, there’s been huge movement on the U.S. and Vietnamese sides,” Boivin said. “It’s very encouraging to see.”
Yet the United States’ overall pace of action on polluted former military bases in Vietnam has been slow. Officials in Vietnam and the U.S. have not settled on an exact cost, but the price tag to clean up Vietnam War-era hot spots would run into the tens of millions of dollars.
“There’s no question that there are levels of dioxin in Vietnam that are harmful, and there is no doubt that U.S. and South Vietnamese forces storing it there has had a cause and effect,” said Michael Marine, the U.S. ambassador to Vietnam from 2004 to 2007.
“It’s a relatively easy argument to make that the U.S. should help to address this issue.”
The impact of Agent Orange isn’t felt only by soldiers and civilians who were directly sprayed. The chemical has had a lasting effect in and around the bases where it was stored -- and spilled.
When Nguyen Van Dung took a job cleaning sewers at the Da Nang airport in 1996, he didn’t know that U.S. forces had stored hundreds of thousands of gallons of herbicides there during the Vietnam War or that those herbicides contained a highly toxic compound linked to more than a dozen illnesses. He didn’t know that the compound had soaked into the soil and remained there at dangerously high levels.
Dung moved with his wife, Thu, and their healthy infant daughter into a one-room cinder-block house next door to the former U.S. air base. During the next 13 years, Dung and Thu, who also works at the airport, had two children with devastating illnesses, including rare blood and bone diseases, that the couple suspect were caused by contamination at the airport.
Their second daughter died when she was 7, and now their 10-month-old son, who suffers from the same ailments, requires painful blood transfusions every month to stay alive.
“I am a man, and men seldom cry,” said Dung, 41, who sat cross-legged on the floor in his home, tears welling in his eyes as Thu cradled the frail infant in her lap. “But every time my son has a blood transfusion, I cry.”
During the last three years, Hatfield and Vietnamese scientists measured levels of dioxin in the blood and breast milk of workers at the Da Nang airport that were as much as 100 times higher than WHO safety guidelines.
Dioxin is considered the most persistent toxin known. In the environment, its half-life can be decades, meaning it takes that long for the chemical contamination to diminish by half. In the human body, the half-life of dioxin is about 7 1/2 years. That means that, not even a decade ago, some residents tested by Hatfield could have had even higher levels of the toxin.
The contamination at Da Nang isn’t confined to the air base. Scientists also found that dioxin from the herbicides had seeped into nearby Sen Lake, where for decades residents bought and sold fish.
The dioxin levels in the fish and in sediment are so high that the Vietnamese government prohibited fishing and swimming in the lake and moved families living close by. The government also sealed the contaminated site with concrete and built a wall around the lake to keep residents out, although reporters on a recent trip to the site met teenagers who were fishing in the lake.
For more than 10 years, Pham Thi Cuc, 74, grew lotus flowers and kept a fishery on the picturesque lake just west of the Da Nang airport. Her business was shut down in 2007 after studies by Hatfield showed that dioxin levels in the lake’s sediment were about 40 times greater than global safety standards.
Blood drawn from Cuc showed that she had some of the highest levels of dioxin ever measured in Vietnam, more than 50 times greater than WHO standards. Her children, who worked with her on the lake and ate large quantities of contaminated fish, also had high levels in their blood.
Although none of them is ill, Cuc said she has lost 10 pounds since the tests because she’s terrified about how the dioxin might affect her children and grandchildren.
Studies have shown that dioxin exposure raises the risk of cancer and other diseases, but it can take decades for its effect on the body to show up, and some exposed people will never suffer ill effects. Scientists believe the chemical disrupts cell development and can even alter a person’s DNA.
In 2006, the EPA began providing technical assistance as a way of contributing to efforts by the Vietnamese and private philanthropic organizations, most notably the Ford Foundation, to find inexpensive ways to eliminate the dioxin at the airport and in Sen Lake. In October of last year, the U.S. Agency for International Development signed a $1.4-million contract to research how best to clean up the site, a study the agency says will take three years.
But that won’t alleviate Cuc’s fears about the damage that has already been done.
“I cannot stop worrying about health problems with my children and grandchildren,” she said. “I am old now, so I don’t worry about my health. But I care very much about them.” The money allocated by Congress also falls far short of what it will take to clean up the Da Nang site, let alone the dozens of other hot spots scattered throughout southern Vietnam.
A report from the Congressional Research Service released in June quoted cost estimates to clean up the Da Nang air base at about $17 million; the Vietnamese peg the cost to clean up the three major hot spots at about $60 million.
“We both have opened the door to say freely what we think,” said Le Ke Son, deputy director of Vietnam’s General Environment Department. “I know the U.S. government cannot do everything, but I think they should show some sympathy to Vietnam for what has happened.”
