HAMPTON ROADS, VA.   December 12, 2004

Danger Dismissed: How the Pentagon downplays
the risks of depleted uranium weapons

Uranium Dust Leaves a Trail
Matt Rohman returned from the Gulf War with many medals and a long list of unexplained health problems. He says he encountered depleted uranium dust.
Photo by Sangjib Min/Daily Press








While U.S. forces fight in the streets of Iraq, scientists are finding more evidence that the depleted uranium weapons we've given them to defeat the enemy are a hazard to friend and foe. The weapons, first used in the Persian Gulf War, provide a decided battlefield advantage. But the mildly radioactive toxic dust that results when they're used successfully also might be why veterans of the 1991 war have a disability rate three times as high as those for Vietnam and World War II vets.

The Pentagon dismisses any link between those illnesses and depleted uranium. This week, the Daily Press takes an in-depth look at the latest science. You'll see why some experts think now is too soon to pull the plug on research into whether cancers and brain damage result from breathing the dust.

You'll find out why the U.S. military uses an inferior process to identify whether our forces have depleted uranium in their bodies and how British vets are signing up for a better test. You'll meet Matt Rohman of York County, a Gulf War veteran who's lost all feeling in his feet and fingers, living every day in pain. Government doctors say his problems are related to the war, but they don't know how or why. Will a new generation of warriors meet the same fate?



'Silver Bullet,' Black Dust 

CHAPTER 1: LOOKING FOR A CAUSE, LOOKING FOR A CURE

Many vets suspect the magic weapon of the 1991 Persian Gulf War caused their continuing health problems.  The Pentagon dismisses the dangers.
 
BY BOB EVANS
247-4758

December 12, 2004.

 

 Photo Gallery
Looking for a cause.
Looking for a cause.

 Chapter 1 in brief

What is it?
It's a byproduct of making "enriched uranium" for nuclear weapons and fuel. "Enriched uranium" is somewhat misleading because processors take uranium with natural levels of radioactive isotopes, primarily Uranium 238 and Uranium 235, and remove as much of the U-235 as possible. Weapons makers and nuclear plant owners want almost-pure, highly radioactive U-235. What's left behind is primarily U-238 (other isotopes remain, in very small quantities). That substance has about 40 percent less radioactivity than natural uranium and is "depleted uranium."


What makes it so important?
It's proven to be the most effective tank-killing weapon ever. A round of depleted uranium no bigger than your little finger can stop a top-of-the line tank without depleted uranium armor. The weapons get sharper as they hit and plow through thick steel. They also create fireballs of thousands of degrees, a potent combination.

What is the controversy?
As they strike, the weapons get sharper by peeling off millions of shards of burning depleted uranium. Those burning pieces become microscopic dust that can be inhaled. Depleted uranium is a mildly radioactive, toxic substance that can cause damage to live tissue and cells once inside the body.

More than a quarter of vets disabled
More than a quarter of the troops deployed in the 1991 Persian Gulf War are disabled, a rate three times greater than for World War II and Vietnam. The reason for the higher rate, especially for undiagnosed illnesses, remains a mystery.

Researchers suspect dust
Some researchers think the mildly radioactive dust that results from depleted uranium weapons is at least part of the problem. Inhaling the dust has been linked to cancer, and particles can alter the DNA of nearby cells in the lungs and other parts of the body, including infection-fighting blood cells.

Pentagon official cites risk studies
Lt. Col. Mark Melanson, a key player in the Pentagon's health program, says studies by the Army and independent labs have found that the risk from depleted uranium isn't significant. He says the lower threshold for danger is well-established.

UCLA researcher: Studies limited
Renowned cancer researcher Dr. Beate Ritz at the University of California, Los Angeles, says scientists have no idea what a "safe" level of exposure to depleted uranium dust might be. Research with human exposures is too limited, she says.


 
For Matt Rohman, the symptoms began about the time that his unit returned to its barracks in Germany after the 1991 Persian Gulf War.

First came a fatigue that sleep couldn't cure. Then severe pains in his joints. His teeth started falling out; his hands and feet went numb. Asthma grabbed his lungs. Debilitating migraine headaches squeezed his skull for days at a stretch. Sleeplessness and other symptoms followed.

Now every day for Rohman, 40, begins the same: waking up in his York County home and trying to figure out how many of the pills and inhalers from the Veterans Affairs hospital he'll have to use.

He wants to swallow just enough to keep his lungs working and the pain at tolerable levels. He's willing to ignore some of his problems to keep some of the drugs in their bottles. That way, his wife, 22-month-old son, 11-year-old daughter and what's left of his life don't disappear into a medicinal fog.

At best, he'll spend the day with no feeling in his feet or hands, watching his kids play, pretty much stuck to a chair or the couch. You could stub out a lit cigarette on any of his fingers or toes, and he wouldn't feel it because of the neuropathy - a nerve disorder that leaves him unable to feel anything. On a good day, he's able to hobble across the room or maybe go out with his family for an hour or two.

The bad days bring pain in his head too intense for him to be much help to his family or himself. Those days can also mean swelling in his extremities so severe, the tips of his toes and fingers look like toadstools and he can't walk at all.

After years of testing and examinations, doctors from the U.S. Department of Veterans Affairs have concluded that something happened to Rohman's brain or central nervous system during the war. The neurological and other symptoms make that clear.

Repeated tests, including brain and body scans, show that his brain is swollen. But there's no evidence of a physical injury or cause, those doctors' reports say, leaving them stumped about why he's so debilitated.

The neurological and other symptoms that Rohman suffers are mirrored in tens of thousands of others who served in the war. When Rohman filed his final plea for VA benefits related to wartime service, the document noted that Rohman had 11 of the 13 officially recognized symptoms consistent with Gulf War service-related illness. One of the 13 applied only to women.

The government lists 20 active theories of what caused these problems.

But it provides no answers.

It doesn't even know how many veterans have these problems or where they live. All that's known is that of the 697,000 who deployed in the war, more than 183,000 had service-related disabilities at the end of 2003, with thousands more applications pending. That's 26 percent of the total, three to five times higher than the rate of disability after World War II (9 percent), the Korean War (5 percent) and the Vietnam War (9 percent) for a comparable period.

All from a war that lasted 100 hours, while the others went on for years.

Why?

Perhaps it was the highly potent bug repellent that the military used to keep away the sand fleas and other pests in the deserts of Iraq, Saudi Arabia and Kuwait. Perhaps it was the experimental pills that troops were ordered to take to ward off the effects of disease and chemical weapons.

Perhaps it was the residue of their own government's most effective weapon for defeating enemy armor - the tank-killing projectiles made from depleted uranium.

In the past few years, while the media and public have been paying attention to another war in the region, doctors and researchers have been finding out more about depleted uranium and how it might be responsible for some of the problems suffered by veterans of the Gulf War. Some of this research hasn't been made public yet, while other findings made ripples only among doctors and professors still in the hunt for a cause and a cure.

There's now physical evidence that depleted uranium, once in the body, migrates to the brain, lungs, bones and testicles of rats and mice. Researchers have found that even a single particle placed in contact with human bone cells can set off a chain reaction of cell and chromosomal abnormalities of the type thought to cause cancer.

They've also found that rats with depleted uranium in their bodies develop tumors and cellular mutations consistent with cancer. And that mice who breathe in tiny bits of the metal - just like the soldiers on the battlefield - get genetic mutations thought to be indicative of cancer.

PENTAGON UNWILLING TO FUND NEW RESEARCH INTO ILLNESS

Despite their efforts, these researchers haven't been able to show why brain scans on Gulf War vets show abnormalities that don't appear in scans of other servicemen and women who didn't go to the war. They just know that it's further proof that there's a real problem among those vets.

They also can't say why men and women who deployed in the Gulf War are twice as likely as others their age to get a fatal neurological disorder known as ALS - Lou Gehrig's disease.

The questions demand answers. To get them, more money and scientific patience is needed, these scientists say.

But the main source of that money for the past 13 years - the Pentagon - says it isn't interested in pursuing new research into the health problems of its former soldiers. Especially when it comes to studying the health effects of using depleted uranium on the battlefield, a use that gives the United States and its allies a lopsided advantage in ground wars.

Pentagon officials have long dismissed the possibility that any of the veterans' problems are the result of the radioactive toxic dust that results when depleted uranium weapons hit hard targets. This fall, they released a $6 million study that they labeled "Capstone" - a title picked because they say it should close the book on whether inhaling depleted uranium on the battlefield is a health risk worth considering.

A number of scientists say it's too soon to stop investigating the possible dangers of these weapons, especially when there have been so few experiments that show what happens when animals or humans inhale the special type of dust created when depleted uranium weapons hit their targets.

None of the recent research that points to possible problems with the weapons was included or addressed in Capstone, not even the work performed by government scientists or researchers financed by the Army and Department of Defense. The Army officer who oversaw the study says that's because there was a conscious effort to base the work on "mainstream science," instead of "preliminary data."

Critics say that's the government's way of simply ignoring the emerging and potentially damning evidence on the subject. With the building body of data, they say, this is no time to label something the final word on depleted uranium's dangers.

The skeptics include a panel of scientists, doctors and veterans appointed by the Bush administration to study the nature and status of research into the cause of the veterans' illnesses. The panel issued its first report last month and said more research into possible health effects from depleted uranium was needed.

"We're not finished," says Lea Steele, the panel's scientific director.

The committee's report says poorly planned and administered research programs are partly to blame for having so little to show for the $247 million spent on research into Gulf War illnesses so far. It points no fingers, but it does note that 74 percent of that money has been controlled by the Pentagon and that most of it has gone to support the now-discounted idea that stress and psychological problems account for the physical symptoms that vets suffer.

Steve Smithson is a member of the panel and the assistant director of the American Legion's Veterans Affairs and Rehabilitation Division. He says the Pentagon has been trying to prematurely end the debate about possible health hazards from depleted uranium for years.

"These are very effective weapons," he says, "and they want to keep them."

WEAPONS' POTENTIAL DANGERS WERE KNOWN FOR DECADES

Depleted uranium was used in combat for the first time in the Gulf War. The weapons proved so effective, troops began calling them "The Silver Bullet," in honor of their near-magical ability to kill the enemy.

The weapons enable U.S. tanks and Bradley Fighting Vehicles to fire accurately and decisively from much greater distances than other anti-tank weapons used in ground combat. That means U.S. troops can kill the enemy before the enemy can fight back.

Last year, when Operation Iraqi Freedom began, the weapons' effectiveness played a big role. It was a reason commanders said they could whip Iraqi leader Saddam Hussein with a smaller, lighter - but more mobile - force than they used in the 1991 Gulf War.

Before that, many people thought that depleted uranium wasn't much more than low-level nuclear garbage.

Depleted uranium is the byproduct of making "enriched uranium" for nuclear weapons and fuel. The process involves stripping natural uranium of its most radioactive components for use in bombs and power plants. What's left is "depleted" uranium.

In the early days of making nuclear weapons, this byproduct was considered a problematic waste. But almost immediately, weapons researchers began trying to make something with it. It took more than 20 years, but by the late 1970s, they'd succeeded. The Army, Navy and Air Force each had a weapon using the material.

But they had to wait to see their creation anywhere except a test range. The first war that involved U.S. forces using tanks against hostile forces who also had tanks was the Persian Gulf War.

One of the weapons' special properties creates what all acknowledge is the downside of these weapons.

When those weapons strike something hard, they slice through the target, getting sharp where other metals get dull. They get sharper by shedding millions and millions of tiny bits of flaming depleted uranium, spitting out the bits like shavings from a pencil in a high-speed sharpener.

Once cool, those bits become mildly radioactive toxic black dust particles, most of them small enough to inhale deep into the lungs. The Capstone study says those toxic particles will likely remain in the lungs for years.

U.S. researchers have known that the weapons' use created a long-lived radiological risk to the lungs since at least the early 1980s. They've also known that these tiny bits of black dust pose a potentially catastrophic health hazard for troops on a battlefield.

None of that was revealed publicly when the weapons were put to use. It wasn't until the mid-1990s that the government officially and publicly acknowledged that troops in the Gulf War had been exposed to this hazard and should have been warned and trained about the dangers beforehand.

By then, thousands and thousands of troops had started suffering the debilitating pains, neurological problems and other symptoms.

Rohman was one of them.

'WE ACTUALLY SLEPT UNDENEATH DESTROYED TANKS ...'

For three months after the fighting stopped, Rohman and his buddies in a 3rd Armored Division combat engineer squadron were ordered to crawl around in the black dust left over from successful shots of depleted uranium.

He was ordered to live and breathe in it while finishing the job of destroying damaged Iraqi tanks and munitions, to make sure that the enemy's equipment couldn't be used again.

"We actually slept underneath destroyed tanks and stuff because we figured they wouldn't fire at their own destroyed vehicles," Rohman says.

For months, the black dust covered many of those vehicles, rubbing off on Rohman's clothing, getting on his skin and often into his food and water.

Hundreds of other soldiers were ordered to do the same work, while thousands of others might have come in contact with the dust through curiosity or happenstance.

Neither Rohman nor the military can say how many of them got sick like he did. Rohman says none of the other soldiers from his unit came from nearby towns or cities, so he lost touch with them while focusing on his own deteriorating health. Researchers say the military didn't keep, or pursue, the kind of information that would help them make such determinations. They also say one of the biggest obstacles to solving the riddle of the illnesses is that people who appear to have the same experiences reacted differently - some getting ill and others staying well.

Many soldiers didn't pay the black dust any notice during the war because the military had never told them about the dangers.

"We didn't know any different," Rohman says.

The Pentagon acknowledged seven years after the war was over that it should have provided training that advised troops to avoid contact with the dust or to use safety masks and suits in the situations that Rohman described.

Instructions on depleted uranium weren't added to the Army's regular training program until the late 1990s. Since then, the requirements for telling troops about depleted uranium have been gradually relaxed for troops who don't fire or handle the weapons.

The Army has a long list of medical and training requirements that must be met before a soldier is supposed to be sent off to war. The checklist for Transportation Corps soldiers deploying from Fort Eustis to Iraq is long. But for the past two years, it hasn't included a requirement that soldiers in transportation units receive depleted uranium hazard training, even though the Army's own radiological experts said in 1997 that they should.

Military and medical officials say it's too early to tell what the effect will be on troops involved in the continuing fighting in Afghanistan and Iraq.

Department of Defense policy - spurred by members of Congress critical of the way that the military handled health complaints after the Gulf War - requires all soldiers, sailors and airmen who come home from overseas wars to fill out a multipage questionnaire about their health and what they experienced.

The only specific mention of depleted uranium exposure on the questionnaire involves one item near the end of a list of 22 possible exposure risks. The list includes such mundane items as "paints," "sand/dust" and "vehicle or truck exhaust fumes." Some soldiers returning from Iraq say that because they were never given instruction on the possible hazards, they didn't know what to choose when given the options of "No," "Sometimes" or "Often" on this question.

Army, Air Force and Navy officials say anyone who checks "Sometimes" or "Often" is questioned further and tested, if necessary. They also say any man or woman in the military who deployed and asks for a test for depleted uranium will be given the test, no further questions asked. Department of Veterans Affairs officials say the same applies to those who served in the Persian Gulf War.

PROMISE TO PERFORM TESTS NOT FULFILLED FOR VETERANS

Yet, Rohman's medical records show that he made VA officials aware of his exposure to depleted uranium six years ago. He's sure that he told them earlier, but many of his records have been lost, and the earliest date that he can document is 1998.

When the Daily Press called the VA administrator responsible for the local testing program to find out why this problem persisted, she immediately agreed that a mistake had been made and took steps to bring Rohman in for evaluation. He still hasn't been tested.

It isn't clear whether things have gotten any better for veterans of the more recent fighting in Iraq.

The Government Accountability Office, Congress' investigative arm, checked in the past year the health forms filled out by more than 1,000 troops who'd returned from the Gulf War. It found that very few of those who'd chosen "Sometimes" or "Often" got tested, said Dan Fahey, a congressional adviser who participated in a briefing on the study.

Steve Robinson, executive director of the National Gulf War Resource Center, a veterans advocacy group, says he's talked to dozens of soldiers just back from the current war who told him that doctors can't diagnose their ills but have refused to test them for depleted uranium exposure.

The soldiers even showed him medical records and other paperwork to prove it, he says. They won't go public for fear retaliation from the military.

Robinson and Smithson say they won't be surprised if there are thousands of veterans with undiagnosed, unexplained illnesses once the totals are in from Operation Iraqi Freedom and its aftermath. Rohman says he won't be surprised, either. He wonders whether this new generation of warriors will succumb to the same undetected poisons that he believes hit him. His brothers still wear military uniforms and could be called to combat tomorrow - one a Marine the other in the Army.

PENTAGON: WE'RE CONVINCED OUR METHOD IS ACCURATE

The Pentagon will say only that as of October, 20,000 troops had been evacuated from the wars in Iraq and Afghanistan for noncombat-related illnesses and injuries and that, on average, about 5,800 troops are on "medical hold" each day because military doctors haven't finished diagnosing or treating them. Only five people have tested positive for depleted uranium from the most recent war - all victims of friendly fire who had depleted uranium shrapnel in their bodies, the Pentagon says.

Getting tests for depleted uranium exposure from the U.S. military and VA might be a waste of time, anyway, say Robinson and experts who have developed those tests for other countries. "Even the test they offer is a less-than-respected test," Robinson says.

Scientists overseas have spent years creating a more accurate method of detecting whether there are even tiny amounts of depleted uranium in the human body.

They say the U.S. government relies on testing procedures and equipment that have a high margin of error and are capable of discerning the presence of depleted uranium only in limited circumstances. They say it's not much of a test if you really want to find radioactive and toxic dust in particles small enough to the inhaled.

The British government officially takes the same stance as the United State on the dangers of depleted uranium, but it's financed a much more exacting test capable of finding out whether someone has even small quantities of depleted uranium in their system. It doesn't settle whether the depleted uranium is harmful, but it can identify the veterans' who definitely have it in their bodies.

That would be an important step forward, several researchers say.

British veterans of the Persian Gulf War began signing up for the tests in late September.

Rohman would like to take it, but the U.S. military says it has no need to use it or even find out how it works.

"We're convinced that our method is sufficiently sensitive and accurate enough," said Lt. Col. Mark Melanson, manager of the health physics program at the U.S. Army Center for Health Promotion and Preventive Medicine, the Army's public health agency.

'OUR HUMAN RESEARCH ... HAS A LOT OF SEVERE LIMITATIONS'

He says the government labs used to identify soldiers with depleted uranium in their bodies can detect the substance as long as there are at least 3 to 5 nanograms of uranium per liter in a day's worth of urine.

The British test also involves a 24-hour urine sample. But it can accurately detect depleted uranium when only 0.1 nanogram of uranium per liter is present, making it capable of detecting amounts 30 times smaller or more.

The British also say their degree of uncertainty at these lower levels is less than 1 percent, a much smaller margin of error than the U.S. tests.

Melanson and other U.S. officials say anything below 3 nanograms of uranium in such a sample is clearly inconsequential. They cite studies of the known, respected science involving the health effects of uranium, specifically studies by the U.S. Institute of Medicine and the World Health Organization.

But the co-author of the Institute of Medicine study, as well as an epidemiologist who was asked to review it to make sure it was scientifically sound, say that wouldn't be an accurate reading of the work at all.

Establishing a lower limwit for inhalation of depleted uranium hasn't happened, they say, because too little is known about how the substance reacts with tissues in various parts of the body.

"We have no idea," said Carolyn Fulco, the co-author of the Institute of Medicine study.

Beate Ritz, an epidemiologist and expert on cancer at the University of California, Los Angeles, agrees: "Our human research, as valuable as it is, has a lot of severe limitations."

Ritz, one of the scientists and health experts whom the institute asked to review its work to ensure accuracy, says it might take decades of following Gulf War veterans to have even a hazy picture when it comes to cancer.

Fulco and others note that the Institute of Medicine and the World Health Organization said explicitly that the data on depleted uranium's health effects were limited and that more research needed to be done.

Still, Melanson thinks that the 50 years of research considered by the studies is enough to show that low levels of uranium or depleted uranium in a human's blood, lungs and other body tissue isn't a problem.

Most of that research involved uranium millers, miners and processors.

It fed the government health standards that the Pentagon used in the Capstone study to establish that inhaling or breathing the dust from the weapons shouldn't be considered a significant health risk on the battlefield. Alexandra Miller, a radiobiologist at the Armed Forces Radiobiology Research Institute, says using that research to dismiss the possible health effects of depleted uranium weapons is a mistake.

There are many studies of uranium miners' health that indicate problems, she says. In addition, she says, the studies of miners and millers are, in many ways, irrelevant to the experiences of soldiers on the battlefield.

When it comes to depleted uranium, she says, there simply hasn't been enough research on animals to know what happens when rats or humans inhale the dust from these weapons.

The amount of depleted uranium dust that can be inhaled without harm simply isn't known yet, she says.

"We don't really know," she said. "Not even for a rat."













Of Rodents and Radiation 

CHAPTER 2: FROM THE NOSE TO THE BRAIN

Experiments with rats find that inhaling dust from depleted uranium weapons can cause genetic mutations
 
BY BOB EVANS
247-4758

December 12, 2004.

 

 Photo Gallery
Looking for damage.
Looking for damage.

 Chapter 2 in brief
Does this dust damage the brain?
University of New Mexico researcher Johnnye L. Lewis leads a team investigating whether rats that inhale dust from depleted uranium weapons experience damage to their central nervous systems or other body functions. The experiments are designed to accurately mimic the exposures encountered by soldiers on a battlefield.

Radioactive residue bypasses barrier
Lewis' research has found inflammation in the neurological systems of rats after they inhaled microscopic depleted uranium, lending credence to the theory that inhaling the dust can disrupt the neurological system. She also found two rats in one experiment had depleted uranium in their brains. She thinks it's the first documented evidence of direct transfer of the substance from the nose to the brain. If so, that would be big because it means the toxic material bypasses much of the body's normal defense systems.

After chemicals, rats unable to function
Mohamed B. Abou-Donia and other researchers at Duke University have documented various problems that result from exposure to chemicals and other substances found on the battlefield in the Persian Gulf War, including depleted uranium. In one experiment, they found that rats lost their ability to perform simple tasks after exposure and that the chemical composition of their brains had been affected.

Vets with shrapnel OK, Pentagon says
Several dozen soldiers who carry depleted uranium shrapnel in their bodies from "friendly fire" incidents during the 1991 war are regularly examined at the Baltimore VA Medical Center by doctors and researchers. The multiyear effort also includes troops who think they inhaled dust from the weapons. Melissa McDiarmid, who heads the study, says none has exhibited significant health problems attributable to the weapons aside from the physical injuries suffered in battle. That's good evidence that internal exposure to pieces of the metal much larger than the dust isn't hazardous, she says.

Blood cells altered after particles inhaled
Richard Albertini, a nationally recognized cancer expert at the University of Vermont, is part of McDiarmid's team. He found that some of the veterans with shrapnel experienced genetic damage of a type thought to indicate cancer. To test the theory, a researcher in New Mexico examined rats that inhaled bits of depleted uranium. He found the rats had the same type of genetic damage as the soldiers, solidifying the link between the damage and the depleted uranium.

She looks for what happens to cells
Alexandra Miller has looked at how exposure to depleted urainum affects human cells. When bone cells were exposed, there were mutations of a type that many scientists consider to be the first steps of cancer. When those cells were injected in animals, tumors developed. Her work was conducted at the Armed Forces Radiobiological Research Institute.

Is it one of many possible causes? Depleted uranium is among many possible causes of Gulf War vets' unexplained illnesses, the Research Advisory Committee to the secretary of veterans affairs said: chemical weapons; biological weapons; infectious agents; specific individual vaccines; multiple vaccines; pyridostigmine bromide; antibiotics, antimalarials; generalized deployment stress; traumatic experiences; physical stressors; oil-well fire smoke; depleted uranium; insect repellents; pesticides; diesel fuel and fumes; jet fuel; chemical-agent-resistant coating; contaminated water; contaminated food; sand.
Details On Thursday in Chapter 6

 THE SERIES

Part One: Looking for a cause, looking for a cure
In a New Mexico laboratory, researchers have been sliding rats into clear Plexiglas tubes with small holes at the end, openings just big enough for the animals' noses to poke through. Once in the tubes, the rats' noses jut into a central space called a plenum. All the air that they breathe comes through that space.

The plenum sits at the center of the tubes, like the hub of a big Plexiglas wheel. When the experiment begins, the air in the plenum is laced with carefully measured, breathable specks of depleted uranium.

Depending on the dose, the rats spend 15 minutes to six hours in the tubes, breathing the uranium-infused air. The researchers carefully have determined the amount of uranium and the length of time to mimic what happens to soldiers on a battlefield.

Afterward, some rats are dissected to find out whether the uranium that they breathed shows up in their brains, lungs, livers, larynxes, tracheas or bronchial lymph nodes. The rest of the rats will meet the same fate a few days, weeks or a year later - to test long-term effects from the same exposure.

The goal is to see whether the tiny pieces of uranium have migrated through their bodies into places that might explain the illnesses suffered by veterans of the 1991 Persian Gulf War.

Lovelace Respiratory Research Institute in New Mexico, home of the Plexiglas tubes and the rats, is one of the few places in the world where scientists are able to accurately simulate what happens when impurities in the air are inhaled. Some of the groundbreaking research on the effects of air pollution has been done there, and the U.S. military has turned to this lab since the 1970s to try to determine the health effects of inhaling depleted uranium.

Lovelace's labs typically are used to investigate hazards to the lungs. Government engineers and scientists have known for decades that the tiny bits of depleted uranium created when the weapons are used pose a health hazard in the lungs and kidneys. They've used computers and other methods to try to determine the details.

The Pentagon has spent millions of dollars to prove that there's no significant radiological or toxicological risk from the pieces of depleted uranium on a battlefield that are small enough to be inhaled. Their studies have focused on potential damage to the kidneys and lungs, where decades of science based on studies of uranium miners, millers and processors predict the most significant effects will be shown.

Scientists in New Mexico are looking at those organs, but they have their eye on a different, more important target this time: the brain.

In the controversy over depleted uranium weapons, nearly everyone agrees that soldiers and others in the immediate area of a blast at the time of impact might be endangered. They also agree that people who later crawl around in the dust or on the destroyed vehicles should use protective gear.

The big disagreement involves whether the dust can simply blow around in the desert away from the explosion, be inhaled, and kill people or make them sick. If this type of minimal contact is harmless, it means depleted uranium is an unlikely cause of the debilitating illnesses suffered by many Gulf War veterans.

If inhaling just a little bit is shown to cause dysfunction in the brain, central nervous system or other parts of the body, the U.S. military might be forced to give up using one of its most effective weapons for land warfare.

The Pentagon has dismissed this danger repeatedly and says there's no serious harm from inhaling depleted uranium on the battlefield - not when someone is in a tank struck by one of the weapons and certainly not afterward, from the dusty residue.

A number of scientists say that's a premature conclusion and that important questions need to be answered first.

SIMULATED MARCH THROUGH DESERT YIELDS A SURPRISE

One of those scientists, professor Johnnye L. Lewis of the University of New Mexico's College of Pharmacy, is trying to find out what happens to the brain and other parts of the central nervous system when someone inhales a lot of the dust and what happens when they inhale a little.

Unless there's evidence that depleted uranium is somehow getting into the brain or central nervous system, it's unlikely to be linked to the neurological and physical problems that many Gulf War veterans suffer. Doctors haven't been able to figure out why the veterans have those medical problems, and little is known about the effect that depleted uranium has on the brain.

The Army officially says depleted uranium is entirely safe in these scenarios, but it does want to know more. So it's financing Lewis' work.

Some of the tasks in Lewis' experiment are done with colleagues at Lovelace. But most take place in her lab at the university, a few miles away.

Before exposing the rats to uranium, Lewis and her colleagues spent months analyzing data, reading research reports and talking to Army generals about how troops move around during a war. They had to find other labs, such as Lovelace and Lawrence Livermore National Laboratory in California, where the different parts of the experiment and analysis could be authoritatively done. The goal was to design experiments that duplicated, as accurately as possible, what real soldiers on a battlefield encountered, Lewis says.

Once the scientists were satisfied, the Lovelace rats went to work.

In the first year, Lewis and her co-workers tested what they called the "tank-impact scenario," which involved exposing several groups of rats to very high doses of uranium (500 milligrams per cubic meter of air) for 15 minutes. That experiment simulated what would happen to someone in an enclosed area, such as a tank, when a depleted uranium weapon struck it.

What came next - detecting the very small quantities of uranium that entered the rats' bodies - takes specialized equipment, Lewis says.

To analyze the rats' brains, for instance, Lewis and her co-workers used a machine to cut the brains into slices thinner than 4/10,000th of an inch.

She also had to find another lab capable of detecting small quantities of depleted uranium in such small samples without destroying them.

Lewis picked Livermore, where a particle accelerator the size of a football field bombards the brain slices with protons. The barrage of protons produces X-ray signals and other readings that allow scientists to determine the presence or absence of uranium and other substances, as well as how much there is in the sample being tested.

When the Livermore scientists did their analysis during the first stage of the experiment, they found no evidence of uranium in the rats' brains, Lewis says. Some of the rats died from kidney damage before they were scheduled to be sacrificed and analyzed, but this was not too surprising. Years of research on uranium miners, millers and processors showed that the kidneys are particularly vulnerable during exposure to uranium dust.

Then the scientists began testing what they call the "march-through scenario," simulating what might happen if soldiers were ordered to walk through an area where tanks or other equipment had been hit with depleted uranium weapons. In this scenario, the rats are exposed to very small quantities of uranium (only 1 milligram per cubic meter of air) for six hours, Lewis says. Nothing remarkable happened.

The next phase involved finding out what happened if the insides of the rats' noses had been irritated by dust, like the small-grained Iraqi desert sand, before the animals are exposed to the uranium.

To do this, the lab used a component of bacteria that produces the same kind of bodily reaction as the powdery sand that blasts at troops in the Iraqi desert. After the irritation, the rats got the low dose of uranium in their air tubes.

This time, the rats had an important story to tell.

"In that case, in a small subset of animals, we did see uranium in the brain," she says.

The depleted uranium was even tracked from one part of the brain to another, linked by a neural pathway. That means it could go deeper in the brain, Lewis says.

The results are preliminary and involved only two of six rats in one group, But Lewis says the implications could be very important as the experiment is repeated and if the same results occur. She says it will be at least a year or more before she can say for sure how significant her findings are.

Lewis expects this phase to produce the best test of what most soldiers experienced in the war.

"If somebody's inhaling dust in the desert, they're likely to get some sort of irritation," she says. Later, when they walk or drive near battle sites, the dust would have been kicked up by others walking or driving ahead of them or by the winds, she says.

EXPERIMENTS COULD EXPLAIN HARM TO NERVOUS SYSTEMS

Scientists generally think that the body has a natural protective barrier called the blood/brain barrier. When impurities, such as toxins, get into the body, they are generally absorbed into the bloodstream. Blood cells, enzymes and other factors then break down those toxins before they get to the brain, protecting it from harm.

It appears that the uranium found in those two rat brains bypassed that process and is the result of direct neural transfer, Lewis says. That means the uranium probably went directly from nerve endings in the nose to the olfactory tissue in the brain, bypassing cleansing agents in the blood.

"I feel some confidence that this is a plausible pathway," Lewis says. If so, toxic aspects of inhaled uranium might also be carried directly from nerves in the nose to other parts of the brain to do damage elsewhere - and might explain many of the problems that Gulf War veterans are having, she says.

Those organs and parts haven't been looked at yet, she says.

If the migration of uranium to the brain can be repeated with more rats, the next step is to see how far into the brain the uranium can go, whether it reaches the spinal cord and central nervous system, and what effect it has, Lewis says. The big question is whether depleted uranium can be linked to the neurological problems experienced by Gulf War veterans.

Mohamed B. Abou-Donia and other Duke University researchers tested that possibility with rats and found evidence that the answer is yes. Because of tight restrictions placed on depleted uranium (the military and Department of Energy strictly regulate its ownership and use), they used a chemical compound very similar to the toxicity and radiological properties of what's used in military weapons. The substitute, uranyl acetate, is frequently used by military and other government researchers as a substitute for depleted uranium in experiments.

Abou-Donia and the scientists at Duke injected rats with various concentrations of the compound and found that high doses killed the rodents. Low doses significantly affected their ability to perform several sensory and motor-skills tests, such as gripping and walking on a beam. When they examined those animals' brains, they found changes in chemicals that affect how well the brain could function.

"The present results suggest that low-dose multiple exposure with uranyl acetate causes long-term neurobehavioral deficits after the initial exposure has ceased," the Duke scientists wrote in the journal Pharmacology, Biochemistry and Behavior in 2002. They said the work showed that the weapons' use could affect the central nervous system, as well as the peripheral or neuromuscular system of the body, and that more research was needed.

SCANS OF THE BRAIN SHOW REDUCED CHEMICAL LEVELS

Rats and mice can tell us much about how chemicals will affect the human body. But sometimes, exposures that cause damage to the little animals do nothing to humans.

Do the illnesses suffered by Gulf War vets have a link to the brain?

A number of researchers have used brain-scanning equipment to study that question and say the answer is yes.

Using the scanners to look at the brains of sick Gulf War veterans, they've consistently found evidence of reduced levels of chemicals required for proper brain functions.

In the veterans, the scans zeroed in on parts of the brain thought related to chronic fatigue syndrome and the veterans' neurological problems.

Researchers say it's unlikely that these brain abnormalities existed before the war because the soldiers' behavior, physically and mentally, would have been noticeably impaired and prevented deployment. But the tests can't confirm what caused the problems or exactly when they began.

The suspects for the cause include depleted uranium dust, the use of heavy-duty bug spray, experimental anti-chemical-warfare medicine, vaccinations for diseases peculiar to the Persian Gulf region, genetics and exposures to toxins after the war. Some of those are known to affect the brain; others are being evaluated.

So far, the uranium in Lewis' experiments has shown up only in the olfactory bulbs of the rats' brains, an area where damage isn't likely to cause the symptoms that Gulf War vets suffer.

The smaller particles might be more dangerous, she says, because they're more likely to end up in the nose and therefore are available for transport into the brain. These smaller, lighter particles are also the ones more likely to be in the air - at nose level - hours, days or months after use of depleted uranium weapons, kicked up by vehicles, boots or winds.

Lewis suspects that in subsequent experiments, with longer exposures or higher doses, there will be evidence of depleted uranium migrating deeper and deeper into the brain, past the olfactory bulb and into places that might be linked to the debilitation that some of the veterans have experienced.

It's possible some people, and some rats, are more capable of withstanding the onslaught of the dust or uranium, perhaps because of stress, genetics or a combination of factors, she says. That would explain why some rats' brains succumbed to the one-two punch of dust and uranium and others didn't. It might also explain why some soldiers have come down with these symptoms, while others in their unit didn't.

SUSPECTED PREDICTOR OF CANCER FOUND IN VETS' BLOOD

Lewis says she hasn't completed the part of her research that involves looking at whether the inhaled uranium changes the neurochemicals in the brain - the chemicals that make the brain function well or poorly. That would help show whether inhaled uranium affected the neurological health of veterans exposed to it.

Her research follows work by other scientists who found that tiny pellets of depleted uranium implanted in the bodies of rats have resulted in collections of uranium in the brains, bones, kidneys, testicles and lymph nodes.

Terry C. Pellmar, a researcher at the Armed Forces Radiobiological Research Institute, found evidence of changes in the brain as a result of those depleted uranium implants.

Some of the rats initially exhibited loss of mental function, but the effects weren't substantial or long-term, she says. Tests given to Gulf War vets with shrapnel in their bodies have shown no demonstrable evidence of impairment in their mental capacities either, she says. Memory loss, confusion and other mental impairments are among the symptoms that other veterans of the war complain of.

The Pentagon and the U.S. Department of Veterans Affairs have been following several dozen Gulf War veterans who have small pieces of depleted uranium shrapnel in their bodies, testing them periodically for various health problems and indicators of carcinogenic and genetic abnormalities. A few soldiers thought to have inhaled depleted uranium dust are also in the study.

The most recent installment of this continuing study said no significant harm to the soldiers had been found, other than the obvious wounds of war that they'd suffered. The Pentagon often points to this research when asked about the health effects of the weapons, noting that these veterans likely have larger quantities of depleted uranium in their bodies than anyone who inhaled some dust on a battlefield.

What Pentagon officials don't mention is what some researchers in the program think is a potentially important finding.

Richard J. Albertini of the University of Vermont's Vermont Cancer Center is one of several co-authors of the shrapnel study. His part of the work included examining cells taken from the veterans to look for genetic changes that might prove harmful.

Albertini's specialty involves research into the hypoxanthine-guanine phosphoribosyl transferase, or HPRT, gene, one of the 30,000 genes that every human being has in their cells.

Albertini is particularly interested in HPRT genes in T-lymphocytes - white blood cells important to the body's ability to ward off diseases, including cancers.

Albertini said blood samples from three of the 39 veterans in the most recently published shrapnel study showed an increased frequency of mutations of the HPRT gene, compared with earlier samples. The three-out-of-39 ratio is a statistically significant number, the study says.

Many scientists think that increased frequency of mutation in HPRT genes is a predictor of cancer. That's why HPRT was included in the study.

Albertini says the link between HPRT mutations and cancer hasn't been proven. A much larger study than those available to date would be needed to know for sure. Then would come research to determine what rate of increase might be indicative of a greater risk of cancer.

Right now, he says, "it's a canary in a coal mine. Just because the canary dies does not mean the miner is going to die, but it's a warning."

Cancer isn't one of the documented problems experienced by Gulf War veterans, Albertini says. Experts say it's too early to tell whether increased rates of cancer will be part of the problems those veterans suffer, though some forms might become evident now.

RATS THAT INHALED PARTICLES, DEVELOPED MUTATIONS

At this point, what's important about the mutation-rate increase is that it might indicate the possibility that veterans exposed to depleted uranium face increased risk of cancer in the future, Albertini says.

The increased mutations in the HPRT gene among veterans spurred another researcher in New Mexico, Vernon Walker, to hook up more rats to tubes to breathe in uranium.

"Lo and behold, he did get an increase in the frequency" of mutations of the HPRT genes in the rats, Albertini says. "So we think this sort of confirmed our hypothesis."

That hypothesis says "the important exposures are from inhalation, where all blood cells can be exposed, not from the shrapnel in a few where the exposure is local," Albertini adds.

All blood flows through the lungs and lymph nodes as part of the process of carrying oxygen to all parts of the body, while only a small fraction of someone's blood would come close enough to the tiny pieces of embedded shrapnel in veterans, Albertini says.

He says it makes sense that even a tiny piece of radioactive dust in someone's lung would have the potential to alter the genetics of more blood cells than shrapnel or a pellet.

That's why he thinks the potential for long-term harm from inhaled uranium dust is greater than that from shrapnel, especially given the small pieces the military leaves in the body when its doctors decide that more damage would result from surgery.

Albertini says he'd like to test that theory further, but so far, the military hasn't made any samples available from troops with more recent exposures.

Obtaining newer samples is crucial for determining whether there's a link between depleted uranium weapons and the mutations and, ultimately, cancer, Albertini says. The rate of mutations in HPRT genes returns to normal after a period of time, he says, so the veterans of the 1991 war won't exhibit this warning sign forever.

In the most recent examination of the veterans with shrapnel, he says, only two people exhibited the increased mutations seen in the earlier study.

That doesn't mean the other soldiers aren't at a higher risk of getting cancer, he says. The HPRT gene mutations are a marker that indicates that the radiation is having an effect on the blood. But they aren't the mutations suspected of causing cancer themselves. Those mutations are likely continuing, if the theory is correct, and could cause the chain reaction of effects that result in cancer, Albertini says.

Samples from troops exposed to depleted uranium dust in Operation Iraqi Freedom haven't been made available yet, but Albertini says further studies of how HPRT genes react in relation to depleted uranium are being planned. The object is to determine whether the relatively weak alpha radiation from small pieces of inhaled depleted uranium cause the type of mutations in the HPRT genes that were seen in the veterans, Albertini says.

Other researchers have seen similar genetic effects from exposure to depleted uranium. A German study found that 16 British soldiers who reported inhaling depleted uranium during their wartime service had five times the frequency of chromosomal aberrations as a group of 40 people who hadn't been exposed to the dust. The aberrations were of the type known to be indicative of radiation that alters the atomic structure of matter, the study said. None of the British veterans had depleted uranium shrapnel wounds.

Whether those veterans actually inhaled depleted uranium - and how much of it is left in their bodies all these years later - is unknown, the German scientists wrote.

At the time of their research, there was no reliable way to measure whether someone had inhaled very small amounts.

The German researchers noted that studies had found the type of uranium that results in the black dust from depleted uranium weapons remains in rat lungs longer than other forms of uranium. The high, intense heat that's part of forming the depleted uranium dust makes the particles not as prone to be dissolved by the blood and other fluids. On one of the few occasions when scientists have been able to perform an autopsy on a Gulf War veteran thought to have inhaled the black dust, lymph nodes related to the lungs showed unexpectedly high concentrations of particles from the decay of uranium, the German study says.

RESEARCH INDICATES A LONG LIFE IN THE LUNGS

Depleted uranium dust created after the weapons' use and small enough to inhale lasts for years in simulated lung fluid, according to a Pentagon study released this fall. The study says the smaller pieces tended to take longer to dissolve half their mass.

That means those bits, though small, are in contact with living tissue for a long time.

Researchers concerned with the safety of the weapons say that could prove important, as the conventional wisdom in science says that chemical toxicity, not radioactivity, is the likely source of any possible ills from inhaled depleted uranium.

Like other heavy metals (such as mercury, zinc and lead), uranium is a toxic chemical. Like those other metals, it's also a naturally occurring element. Nature puts a certain level of those metals into the food chain, the air we breathe and the water we drink. Mankind and modern life has added more, via air pollution and working with what's found in nature to create plumbing, machines, weapons and other tools.

As a result, our bodies and their waste products, including urine, contain some degree of all these metals.

How much is a safe level and how much is too much is the question, whether it be figuring out safe levels of mercury in fish or how much black depleted uranium dust a soldier can inhale without incident.

The toxic effects of these metals typically act like poisons carried through the bloodstream. They collect in parts of organs - often the kidneys or liver - and can destroy them. Uranium miners, millers and processors exposed to too much uranium dust typically have kidney damage; little tubes in the organs break down and malfunction.

Depleted uranium's radiological properties act differently. Until very recently, scientists thought that the effects of radioactivity occurred in very predictable paths and patterns, depending on the material, how big it was and whether it was emitting alpha, gamma or X-rays.

Like all uranium, depleted uranium emits mostly alpha radiation. Typically, alpha radiation isn't considered very dangerous because its power doesn't go very far and is easily blocked by a sheet of paper, clothing, the top layers of skin and other mundane items.

But once an alpha radiation source gets in the body, it's another story. Then there's no shield to protect the cells and tissue. The radius of alpha radiation is relatively short, but it's long-lasting and therefore powerful.

STUDY ANSWERS ALL QUESTIONS, PENTAGON SAYS

Pentagon and other government officials say risk from that radiation is negligible because the soldiers, even those caught in a tank hit with the weapons, wouldn't inhale enough depleted uranium dust to create a problem.

The military spent five years and $6 million to gather data on what actually happens when tanks and Bradley Fighting Vehicles are hit with depleted uranium. It released the data and its findings this fall in what it called the Capstone Study - a title designed to tell people that their research was the final word on the subject.

Real vehicles and vehicle parts were hit with depleted uranium weapons in a large building in Aberdeen, Md. Sophisticated machines capable of gathering and counting millions of tiny pieces of dust recorded the data. Researchers with respirators, wearing devices that could also collect the depleted uranium and other dust particles in the air, wiped the vehicles down afterward and examined the insides.

It was the most complete and sophisticated examination of what happens when depleted uranium weapons strike a vehicle, Lt. Col. Mark Melanson says. He manages health physics programs at the Army's public health agency, which commissioned the study.

Using the established government standards for acceptable levels of uranium inhalation and ingestion, the researchers in Capstone found that even under the worst circumstances, people in a tank or Bradley Fighting Vehicle hit by a depleted uranium weapon would incur no significant health risk.

They wouldn't inhale enough for there to be a toxicological danger to their kidneys or other organs, the study says. And the tiny bits that remained in the soldiers' lungs, even the ones that stayed there for years and years, would not be of sufficient quantity to pose a radiological hazard anywhere near as great as smoking cigarettes, it says.

Possible radiological problems from the weapons have been dismissed by many in the military for years.

"The issue is chemical, not radiologic, risk," says Melissa A. McDiarmid of the University of Maryland School of Medicine and the VA hospital in Baltimore. McDiarmid directs the government's monitoring of Gulf War veterans with shrapnel in their bodies and has participated in other government-financed research.

McDiarmid says the tiny amount of black depleted uranium dust that a soldier could inhale several hundred feet away from an explosion is inconsequential. Even if particles are inhaled in that scenario, they wouldn't constitute a big enough dose of radiation or toxic chemical to change lives, she says. Fifty years of research based on the experiences of workers in the uranium mining, milling and processing industries prove that scientists have good models to use to compute what is - and isn't - a harmful dose of inhaled uranium, whether it's depleted or not, she says.

CHALLENGING THE MODEL ABOUT HOW RADIATION HARMS

The government standards used in the Capstone Study are based on the research on those occupations and its hazards. Scientists then develop a model of what's safe and unsafe, using computers and theories. Many well-respected scientists say the models are fine but aren't a substitute for testing the models' assumptions out on living creatures or cells. Tests on animals often prove that the models are wrong, they say.

Alexandra Miller is a scientist at the Armed Forces Radiobiological Research Institute. Miller has spent much of the past 10 years testing whether very small particles of alpha radiation can have lasting and catastrophic effects on cells. She and others around the world are challenging the conventional wisdom that it takes large doses of radiation - either in a single blast or prolonged exposure - to make someone sick or die.

The research on uranium industry workers used to support the argument that depleted uranium dust in battlefield situations isn't a significant hazard is limited, Miller and these scientists say. There are studies that contradict each other, that are poorly done and don't really match up with what troops in the 1991 war experienced, they say.

Their point isn't that the weapons are more dangerous than the military says. They simply say that now is too early to reach a conclusion about safety and that more work needs to be done.

In one recent experiment, Miller exposed human bone cells to alpha particle radiation from depleted uranium and other forms of uranium. Scientists have known for years that when uranium or depleted uranium gets in the body, more of it tends to migrate to the kidneys and bone than any other parts.

Miller says her experiments with the bone cells had two significant findings.

First, she found that the cells went through transformation from normal cells to cancer cells. When those cells were then injected into animals, tumors developed. A genetically similar group of animals used for comparison didn't develop those tumors, she says.

Although the precise cause of cancers isn't known yet, scientists think that these sorts of transformations get the carcinogenic ball rolling, Miller says. The results of that experiment weren't too surprising, she says, though they were important.

The surprise came when she started counting how many cells turned to cancer cells and noticed how far away they were from the source of the radiation.

"BYSTANDER EFFECT" BRINGS UNEXPECTED DAMAGE TO CELLS

Scientists have been working with uranium long enough to be able to say with certainty how much alpha radiation a given piece of uranium or depleted uranium holds. Extremely sensitive devices can measure it.

Scientists therefore think that they can predict in advance how far away the radiation effects can be felt.

But when Miller applied those rules of science to the cells in her laboratory, the rules didn't work. Those same rules underlie the Pentagon's Capstone Study.

"We actually got more damage to chromosomes than we expected, based on the number of alpha particles," she says. "That was the first surprise to me, as a scientist."

Other scientists and other experiments have made similar discoveries. Now they're trying to figure out what it means and why it happens.

Miller says the transformations might result from uranium's toxicity, not its radioactivity. But she suspects that it's a combination of radiation and toxicological effects.

The radiation starts the damage, and the toxicological properties carry it further, she theorizes. The radiation causes another change, and the process is repeated, over and over, until many more cells are altered.

Another possible explanation is that the cells damaged by the initial radiation excrete a hormone or other chemical that spreads to a nearby cell and damages it, Miller says. The damage gets repeated, over and over.

No one is sure of the cause, but scientists do have a name for it: the "bystander effect." That simply means cells, chromosomes and genes that are nearby - but not in the path of actual radiation - are affected.

The effect seems to be more pronounced with alpha radiation, as opposed to the other varieties, Miller says.

"It's actually changed radiobiology dogma in the past four to five years," providing a new look at a hundred years of science, she says.

Whether it will also change what science considers a healthy or unhealthy dose of radiation remains to be seen.

So far, the government agencies and industrial groups that set what are deemed to be safe levels of exposure haven't revamped their standards in light of the bystander effect, Miller says.

Now is probably too early for that, she says, but by the same token, it's too early to say we know enough about depleted uranium to decide what's safe.

When Miller published her first paper on how uranium might damage cells, it was 1998.

She says only two other scientists had published experiments on the topic before that. More work needs to be done, she says. Similarly, Miller says, more work needs to be done on inhalation of depleted uranium, as opposed to ingestion.

When uranium is swallowed, most of it passes immediately through the digestive system and is eliminated in body waste. But when a particle small enough to be inhaled directly lands on lung tissue - with no clothing, paper or outer layers of skin to block the path of the alpha radiation - what happens to that lung tissue?

"We simply don't know," she says. "The body of data out there on uranium is limited."

McDiarmid thinks that we do know enough to reach the conclusion that inhaled depleted uranium isn't a significant radiological danger. And she thinks that the failure to acknowledge this might be hurting ill veterans from the Persian Gulf War.

"What we have here is a witch hunt for an explanation," she says, fed by the public's fear of radiation and fanned by opponents of the weapon and ignorance of the actual science.

"The thing I'm worried about with everybody chasing depleted uranium is that we're missing the boat," she insists.

With so much attention on depleted uranium, other possible causes for the veterans' illnesses go unexplored and the veterans aren't helped.

Her most recent research paper about the veterans with shrapnel in their bodies also points to another risk of pursuing this line of inquiry into depleted uranium, known by scientists and others as "DU."

"Questions regarding the long-term health consequences of these exposures have fueled considerable debate regarding continued use of DU in combat," it says.

If the weapons are proven to create toxic dust that swirls around the desert and contaminates the air in virtual perpetuity, the United States, Great Britain and their allies might be forced to give the weapons up. They might also be forced to spend billions of dollars cleaning the dust up and taking it out of the desert.

Lurking in the background of this scenario is the argument by some antinuclear activists, Iraqi physicians - and the former régime of Iraqi President Saddam Hussein - that the black dust left behind from the Persian Gulf War caused deformities, cancers and death for thousands of Iraqi children since 1991.

So far, those statements have been buried behind the curtain of Saddam's tyranny, beyond verification by credible groups. Now that Iraq is open to outsiders and run by a friendly interim government, credible medical and scientific experts have started work to figure out whether these stories are propaganda - or the worst sort of bad news.

The United Nations and other organizations recently began financing studies to determine whether the depleted uranium left behind in Iraq and Kuwait in the two wars are linked to health problems in the two countries.

The head of the U.N. effort - Pekka Haavisto, a former Finnish minister of the environment - said this fall that the British government gave his workers information on places where it used depleted uranium weapons but that the U.S. government hadn't.

U.S. military munitions experts say losing depleted uranium from this country's arsenal would be a disaster - and might cost more soldiers' lives in combat than scrapping the weapons might save.