Dr. Ellen K. Silbergeld is at home in several worlds.
One is filled with test tubes and toxicology classes, another with public policy debates and environmental committees.
A third is filled with homework, soccer, gymnastics, hectic mornings and no-show baby-sitters.
Last month, Dr. Silbergeld, 47, of Baltimore received a $290,000 "genius grant" from the John D. and Catherine T. MacArthur Foundation.
Dr. Silbergeld divides her weekdays between teaching classes or doing research as a professor of epidemiology at the University of Maryland School of Medicine, and working to change public policy in Washington as chief toxics scientist at the Environmental Defense Fund.
In doing so, she has become known as a scientist who has both the ability and desire to halt lab work long enough to argue policy.
On a recent Saturday morning, however, as Dr. Silbergeld swings on a hammock with her 8-year-old son, Nicholas, and husband, Mark, the word "genius" does not spring to mind. (Nor does it upon hearing her voice imitating Godzilla on the telephone answering machine.)
The Silbergelds minus one -- 12-year-old Sophia is at summercamp -- are eating breakfast on the wrap-around veranda of their Roland Park home. In the interlude before father and son rush off to a soccer game, there is a rare moment of familial serenity.
Rare indeed. In the three weeks after learning of the grant -- she's unsure how she will spend the money, but wants to use it "to make a difference" -- Dr. Silbergeld flew to Munich to speak at an international toxicology conference, polished three manuscripts for publication, and finished a third round of experiments that attempt to link blood lead levels in male rats to fetal defects in their offspring.
Meanwhile, Sophia left for camp in North Carolina and Mr. Silbergeld, director of the Consumers Union's Washington office, flew to Costa Rica to speak on free-market economies.
Work vs. home
The Silbergeld formula for the inevitable work-vs.-home crunch consists of "two opposing principles," Dr. Silbergeld says.
"One is: I let my kids really know what I'm doing. They come to the lab. They both have traveled with me. They understand why I have to be out of town sometimes," she says.
"The other is: When I'm at home, I'm at home. When we go on vacation, I leave work behind."
The decision to have children didn't come easily. "When I was working at NIH, children were a huge issue. [Women at the National Institutes of Health] were all fairly much convinced it was impossible to have children and a science career," she says.
But in her mid-30s, after 10 years of marriage, Dr. Silbergeld realized she wanted to try.
"I wasn't under any illusions that it would be easy, but I asked myself: 'Did I not want children because I didn't want children or because it was so hard?' "
And she adds, laughing: "I have never not done something because people made it hard for me."
Called "pleasantly aggressive" by one public health official, Dr. Silbergeld refers to herself as downright stubborn. "It leads one into a lot of trouble," she says.
Persistance, however, often pays when arguing for policy changes.
"Just get in an argument with her. You'll see!" says Dr. Joel Schwartz, a senior scientist at the Environmental Protection Agency, who has done lead research with Dr. Silbergeld and who received a 1991 MacArthur grant. "Her combination of persistence and scientific knowledge is very effective."
Her determination paid off after a young Ellen Kovner, a woman with a bachelor of arts degree in history from Vassar College, decided to join a predominantly male graduate program at the John Hopkins University.
"Her whole outlook is directed.
She is stimulated by the outside world as well as from within," says M. Gordon "Reds" Wolman, a professor in the Hopkins Department of Geography and Environmental Engineering, where Dr. Silbergeld received her doctorate.
It was, in fact, Dr. Wolman's father, the late Dr. Abel Wolman, head of the first department of sanitary engineering at Hopkins, who inspired her commitment to changing policy, Dr. Silbergeld says.
"He gave me the notion that scientific research was important only in so far as it helps us solve problems, not just define problems," she says.
And so on a recent afternoon in her University of Maryland lab, as Dr. Silbergeld used a pipette to place brain cells from young rats into test tubes, her conversation ranged from the experiment to policy changes she'd like to see made.
The work at hand is the third round of tests attempting to prove a hypothesis, developed by Dr. Silbergeld and a former graduate student, that lead poisoning in adult males affects their offspring.
Many scientists have focused concerns about lead poisoning on pregnant adult females, studying how the mother's condition might harm the fetus while overlooking the potential role of lead poisoning in the father.
One assumption was that lead-poisoned males would be sterile and unable to pass along abnormalities, an assumption, she says, "that's kind of kooky."
So far, she says, her research appears to show that changes in fetal brain cells of rats are linked to lead poisoning in their fathers.
How much testing?
The policy changes that Dr. Silbergeld advocates are universal testing for lead poisoning in children and funding for elimination of existing sources of lead poisoning -- mostly house paint manufactured before lead was banned from paint in 1977.
High levels of lead in a child's body can limit the ability to learn, cause behavioral problems and stunt growth.
But some public health professionals dispute the need for such costly measures, arguing that it is unclear how much children are harmed by low lead levels.
In addition, they say, universal lead testing for children will prove so expensive that other programs for at-risk children will suffer.
"Much more effort should go into the activities [such as Head Start] that we know make a difference," says Dr. Claire Ernhart, a developmental psychologist at Case Western, who is conducting large-scalestudy in which children who live in old housing are tracked from birth.
Dr. Ernhart adds: "I don't think that some of what's going on in lead testing is going to make a darn bit of difference."
Dr. Silbergeld disagrees. She points out that universal screening for lead poisoning among children has been recommended by the Centers for Disease Control and Prevention in Atlanta.
"When you have a disease that is largely untreatable, whose early symptoms are difficult to detect and that is so prevalent, then insistence upon universal testing is not extreme," she says.
DR. ELLEN K. SILBERGELD'S ACCOMPLISHMENTS
Here are a few achievements that Dr. Ellen K. Silbergeld views with satisfaction. Many of them, she says, weren't accomplished alone but by team work through the Environmental Defense Fund (EDF) or with other researchers.
Changes in federal or corporate policy
* Early '80s. Played a pivotal role in convincing federal government to phase out the use of lead in gasoline.
* 1982-1984. Was among environmentalists who fought and stopped a revision of how the federal government defines and controls carcinogens such as dioxin, asbestos and formaldehyde.
* 1984. Was among public health officials and environmentalists who successfully had health-related provisions written into Superfund.
* Early '90s. Brought international spotlight on the use of mercury to extract gold from the Amazon River.
* 1990. Played a pivotal role for an EDF team that worked with McDonald's in the switch to paper wrappers from foam containers.Research
* Studies investigating the long-term mechanisms of how lead affects the brain.
* Study showing lead, stored in bones throughout a lifetime, re-enters the bloodstream during menopause so that blood lead levels in older women may rise dramatically.
* Studies of fetal brain cells showing that blood lead levels in males may affect their offspring.
* Early studies looking at dioxin as a hormone -- instead of as a toxic chemical -- which sheds light on the systemic effects of dioxin on the body.
* Development of a lead test that reduces the wait for results to about a half hour. Now being patented by the University of Maryland, the procedure could ease testing and broaden its use.