The U.S. Environmental Protection Agency last week held the first of a series of public hearings to explore the potential health risks posed by electromagnetic fields created by high-power lines and electronic equipment.
The hearing in part reflected the growing concerns expressed by some scientists, educators, and members of the public that the electromagnetic fields are particularly dangerous to children.
Over the past several years, parents in many communities have begun to question whether power lines, which emit low-level radiation, should be placed near homes and schools. These health concerns also extend to computers, microwave ovens, electric blankets, and other home appliances, which also create electrical fields.
The hearing also made clear, however, that the scientific community remains divided on whether, and to what extent, exposure to the fields causes cancer and other serious health problems.
Many experts do agree, though, that power at 60 cycles per second--a frequency commonly used in North America--can produce biological changes in humans.
Last week’s meeting followed release late last year of an epa report that concluded that some scientific studies have suggested a “causal link” between exposure to electromagnetic fields and leukemia, lymphoma, and cancer of the nervous system in children.
But, the report added, there currently is not sufficient evidence to prove that electromagnetic fields can be positively considered a cause of cancer in humans.
A study released by the Congressional Office of Technology Assessment in 1989 came to a similarly mixed conclusion. It did recommend, however, the “prudent avoidance” of excessive exposure to electromagnetic fields until scientists prove or disprove their potential ealth threat.
Although there are no firm answers about the health risks posed by emf’s, educators in several school districts around the nation have become involved in community controversy over their students’ ex posure to such low-level radiation. For example:
A Palm Beach, Fla., circuit court judge late last year upheld his 1989 ruling that prohibits students from using a large portion of the school yard at a local elementary school be cause a power line runs near the fa cility.
Parents had initiated the lawsuit because they were upset the district had built the school alongside the power line, according to their law yer, Lawrence Marraffino. He said the parents will be seeking a liberal transfer policy that would allow them to send their children to other district schools.
“I’m not someone who says we should tear down power lines but you shouldn’t build schools and houses anywhere near those things,” he said. “When it comes to schools and school children, I don’t think you can do any thing differently.”
In Fountain Valley, Calif., educa tors late last year worked with com munity committees in each of the dis4trict’s 11 schools to develop plans to limit students’ exposure to emf’s. The strength of electric fields was measured in each of the schools, as well as in students’ homes.
According to the plan of one school, staff members were told which parts of the school had the highest readings, and were advised to warn students if they played in these areas. Students will also have to sit further away from the video- display terminal when they work in the school’s computer lab.
In 1985, a jury awarded the Klein (Tex.) School District more than $100,000 in compensatory damages and $25 million in punitive damages in its suit against a local power com pany that was planning to install a power line adjacent to a school. Two years later, however, an appeals court overturned the punitive award, and the power company relocated the line to avoid the school.
At the hearing last week, which was held by a special advisory board appointed by the epa to review its : recent report, scientists aired their differences over the potential effects of emf’s.
Several of those testifying expressed skepticism about the alleged health dangers posed by emf’s.
“The bottom line is that the ex perimental record is thin,” said ark Mandelkern, a professor of physics and pathology at the Uni versity of California at Irvine.
Some of the scientists at the forum were representing organizations that are funded by public utilities and the makers of products that proH duce electromagnetic energy. They said the report was biased because it placed too much emphasis on flawed studies or on studies that have not yet been reproduced.
But that view is disputed by Nancy Wertheimer, a clinical-faculty mem ber in the department of preventive medicine at the University of Colora do Medical Center in Denver. In 1979, Ms. Wertheimer was a co-au thor of the first study that suggested that children who live near power- distribution lines may have twice the risk of developing certain types of cancer than do unexposed children. “Any one of the studies has flaws,” Ms. Wertheimer said in an inter view last week, “but it’s unlikely that there would be flaws in that many instances.”
“There is evidence that there may be some kind of risk here, and that evidence in growing stronger,” she said.