Scientist's Death Traced To Seemingly Trifling Mishap -- Tiny Drop Of Mercury Spilled In Chemistry Lab Proves Deadly

LYME, N.H. - It was just a drop of liquid, just a tiny glistening drop. It glided over her glove like a jewel.

Scientist Karen Wetterhahn knew the risks: The bad stuff kills if you get too close.

She took all the precautions working with mercury in her Dartmouth College lab - wearing protective gloves and eye goggles, working under a ventilated hood that sucks up chemical fumes.

So on that sunny day in August, when she accidentally spilled a drop, she didn't think anything of it. She washed her hands, cleaned her instruments and went home.

It was just a drop of liquid, just a tiny glistening drop.

At first, friends thought she had caught a stomach bug on her trip to Malaysia. It wasn't until she started bumping into doors that her husband, Leon Webb, began to worry. Karen, always so focused, always so sure of her next step, was suddenly falling down as if she were drunk.

In 15 years together, she had never been sick, never stopped working, never complained. Leon was stunned when she called for a ride home from work.

A few nights later, Leon drove her to the emergency room. It was Monday, Jan. 20, 1997, five months since she had spilled the drop in the lab.

Just a single drop of liquid. Yet somehow it had penetrated her skin.

By the weekend, Karen couldn't walk, her speech was slurred and her hands trembled. The initial diagnosis of "virus" seemed awfully vague for symptoms that were getting worse every day.

"It's mercury poisoning," Dr. David Nierenberg said. "We have to start treatment immediately."

Leon hung up with relief. At last, they understood the problem. Now maybe they could fix it.

It seemed impossible to believe that anything could be wrong with Karen Wetterhahn, one of those quietly impressive individuals whose lives seemed charmed from the start.

Serious and hardworking, she excelled at everything she turned to - science or sailing or skiing.

Karen was always the brilliant one of the family, the one who would do great things. And she did, becoming the first woman chemistry professor at Dartmouth, running a world-renowned laboratory on chromium research.

It was important work, the kind that could lead to cures for cancer and AIDS. Karen thrived on it.

At home, she would throw great neighborhood parties by the pool, or gather up the family and drag them off to the golf course, or the tennis court, or a kid's hockey game.

"We never knew she was a world-famous scientist," one neighbor said afterward. "She was just Char and Ashley's mom."

Mercury poisoning.

Karen beamed when she heard the news. Finally, something she understood. Something she could explain. They would feed her fat white nasty-tasting pills that would flush the poison out of her system. Science would cure her, she told her husband, giddy with excitement as she sat in bed surrounded by her children and her notes.

Back in January, virtually nothing was known about the extraordinary dangers of dimethylmercury, the rare man-made compound Karen had spilled. Scientists didn't know it could seep through a latex glove like a drop of water through a Kleenex. Doctors didn't know it could break down the body over the course of a few months, slowly, insidiously, irreversibly.

Above all, no one knew how to stop its deadly progress, as it cut off her hearing, her speech, her vision, reducing her body to a withered shell.

Today, because of Karen, the world knows so much more.

Quicksilver, as mercury is called, has long played a sinister game of seduction with science. One of the world's oldest metals, it comes in various forms - some that heal, some that kill. Dimethlymercury, a colorless liquid that looks like water but is three times heavier, is far more toxic than other forms - the kind used in thermometers and batteries and medicine. It's made purely for research and is rarely used.

There was only one documented case of dimethlymercury poisoning this century, a Czech chemist in 1972 who had suffered the same symptoms as Karen and died. A handful of people had been exposed directly to pure methlymercury, another toxic mercury compound, and died.

There was no telling if dimethlymercury would act the same way.

Karen herself was beginning to understand. There was a desperate look on her face as she pointed to the clock when it was time to take her pills. Still, she kept up a brave face, kept saying not to worry.

That was Jan. 31, three days after the diagnosis. A week later, Karen was transferred to Massachusetts General Hospital for a massive blood transfusion that nearly killed her.

Leon was pacing at home again, torn between honoring his wife's wish not to alert her parents and the feeling that she was sinking faster than she knew.

The phone rang. The nurse said Karen wanted to talk to her son, Ashley.

From her hospital bed, the mother struggled. She drooled and moaned and the words just wouldn't come. Ashley, 14, waited uncomfortably. He didn't like the silence. "Hi, Mom," he coaxed, loud so she might hear. It was useless. The nurse ended the torture and took the phone.

"She just wanted to say goodnight," Ashley says, bowing his head to hide the tears when he remembers the last time he talked to his mother. "She couldn't even say goodnight."

Others remember final moments, too, although everything was happening so fast they didn't seem like goodbyes at the time. But friends could see the toll on the scientist's mind and body. They could see her faith fading, even as she continued to talk about being back on her feet for her new spring course. The day the ambulance came to take her to Massachusetts, she cried uncontrollably.

Karen's lab was shut down. Her family, students and co-workers were tested. Her hospital room was checked for airborne mercury from her breath. Federal environmental and health agencies were alerted, as was the state health department. Her car and clothes and house were sniffed with mercury-detectors.

Scientists and doctors around the world offered their services.

"It was an extraordinary outpouring," Nierenberg says.

But Karen was slipping too fast to appreciate it. Ten days after the diagnosis, on Feb. 7, she fell into a coma. Leon told the doctors he was taking her home.

Back at Dartmouth Hitchcock Hospital, her family kept vigil by her bedside, her parents and sister talking to her as her body thrashed and moaned. Leon plastered the walls with cards and photographs: Karen on the golf course, at Disney World with the kids, lunch with her friends Cathy and Nadia, shaking hands with President Clinton at graduation ceremonies in 1996.

Just a tiny drop of poison. And she was fighting it with all her might.

It became too difficult for the children to visit. Even friends stayed home, waiting for the phone call that would tell them it was over.

Her husband stroked her face. Her sister and her best friend washed her hair. Doctors tried treatments never attempted on humans before.

But they couldn't save her from the poison. On June 8, it took her life.

"She didn't suffer," Ashley told his eighth-grade class the next day. "She just stopped breathing."

It was 10 months since she had spilled the drop in the lab, four months after she had slipped into a coma.

Karen Wetterhahn's death was as extraordinary as her life and, in many ways, just as important. Perhaps she had an idea that it would be.

While she could still speak, she urged doctors and scientists to learn everything they could from her accident and to warn the world about the dangers.

The world has already learned so much. It learned that the gloves that were supposed to protect her actually acted as a conductor to the poison. It learned that dimethlymercury, so easy to order in research catalogs, is more deadly than anyone had imagined. Saddest of all, it learned that by the time the symptoms showed, it was too late.

Her funeral took place on a hot summer day to the strains of a flute and a choir singing "Be Not Afraid."

In the packed college chapel, the sense of betrayal was as powerful as the sense of loss. Colleagues wept as they eulogized a modern-day Madame Curie who had sacrificed her life to her cause.

Alone and bewildered, Leon sat in the front pew, looking out of place in his dark funeral suit, tears streaming down his face.

It all seemed like a dream, he says later. No, he corrects himself - a nightmare.

"She loved her work," he says. "It made her happy."

She couldn't have known the risks. She couldn't have known how bad the bad stuff really was. Truth is, no one knew.

Just a tiny drop of liquid. Sweet-smelling. Dense. Deadly.