The recent discovery of high electromagnetic fields in a Sherman Oaks kindergarten classroom exposed the lack of a concerted program to detect EMF hot spots in city schools.
EMF measurements were taken at Dixie Canyon Avenue Elementary School because of a parent's concern about the placement of an electric transformer, not due to the vigilance of school authorities. As the episode revealed, testing for elevated EMFs usually is limited to schools with worried parents or staff.
EMFs have been linked by some studies to a small increased risk of cancer.
This passive approach--which one critic called a "squeaky wheel" policy--has not produced much information about EMF levels in local schools. Only nine of more than 600 schools in the Los Angeles Unified School District have had EMF measurements, district records show.
More testing is likely after the Dixie Canyon flap, which involved a transformer installed inches from the exterior wall of a bungalow classroom. After a parent voiced concern, district safety officials sought measurements by the Los Angeles Department of Water and Power, which obtained a high reading of 107 milligauss at the teacher's desk. Typical readings in homes and offices are less than 2 milligauss.
Parents were particularly upset because the district installed the transformer in 1991--long after the EMF controversy surfaced.
Jeffrey Fried, the parent who raised the issue, said he was incensed that the district "put it (the transformer) seven inches away from the children."
District officials, who have decided to relocate the transformer at a cost of about $100,000, say similar situations could exist on up to 100 campuses where transformers have been added since 1989 to serve portable classrooms and new air-conditioning systems. Rather than install the transformers as far as possible from classrooms, officials said they typically put them nearby to save money and space.
The state Department of Education since 1988 has required minimum setbacks from power lines for new schools and portable classrooms, but the standard does not mention other electrical installations.
Diane Doi of the district's environmental health and safety branch said the risk of transformers creating higher EMF exposures "didn't register. . . . The focus with EMFs . . . was always with the power transmission lines."
Electric and magnetic fields are invisible lines of force that radiate outward from every electrical device, penetrating nearly everything around them--including the human body. If EMFs are dangerous, distance is the best defense because their strength falls rapidly with distance from the source.
Several studies have found a small increased risk of cancer in children living near high-current power lines, and other EMF research has found elevated cancer rates among workers whose jobs bring them into close contact with electrical equipment, such as utility linemen and film projectionists. A smaller number of studies found no connection between EMFs and cancer, and experts generally say a causal link has not been proven.
Recognizing that a definitive conclusion may be years away, some authorities--including state health officials--have called for voluntary adoption of no-cost and low-cost means to reduce exposures, in case EMFs are proven to be harmful.
Such "prudent avoidance" measures, as they are sometimes called, can be as simple as fencing off part of a playground or moving workstations farther from a source of EMFs.
But taking such precautions means knowing where elevated fields exist. And in Los Angeles and many other areas, this data exists for a mere handful of schools.
As a free service to customers, a number of utilities, including the DWP and Southern California Edison Co., take EMF readings in homes, offices and schools by request. Although the DWP has surveyed nearly 600 homes and offices during the past two years, it has only been asked to test nine schools.
Although Edison, the nation's second-largest utility, has measured nearly 3,900 sites during the past two years, fewer than 100 have been schools, said Mark Judy, manager of Edison's EMF education center.
Yet many experts believe there are compelling reasons why such testing should be focused on schools. For one thing, some schools were built near power lines or other electric installations to take advantage of cheaper land costs. By bringing large numbers of children and adults together in one place, schools concentrate any risks that may exist.
"Schools have a special status, because they're public institutions to which people entrust their kids," said Dr. Raymond R. Neutra of the state Department of Health Services, the state's point man on the EMF issue.
State health and education officials say a mandate to test all schools is unlikely anytime soon--particularly because there is no consensus on what EMF levels would be cause for concern.
Testing "will probably continue to be on a public response mode, instead of a blanket 'everybody must do it,' " said Duwayne Brooks, an assistant superintendent of the state Department of Education and member of a state task force on EMF in schools.
Although they are veterans of emotionally charged health scares involving asbestos, lead and radon, school safety officials say they are floundering for lack of standards on EMF exposure.
Several testing initiatives are expected in the coming months. In response to the Dixie Canyon episode, district officials said they will review building plans to pinpoint campuses where transformers near classrooms may be causing heightened exposures.
In a separate study, DWP officials are planning to take EMF measurements at 41 schools that are near transmission lines and substations--although the readings will be confined to school property lines.