Do Power Lines Pose Risk To Public Health? -- Perils Are Theoretical, But Steps Are Being Taken

Strung atop tall steel towers, one of the region's largest power lines runs from just north of Bothell to Maple Valley, past the houses, businesses and schools of the Eastside.

It's been there for years, and at first people just talked about how bad it looked.

But now governments, school districts and community groups are beginning to talk about power lines in ways beyond their aesthetics. They're asking whether electromagnetic fields emitted by lines going through their cities might pose a health danger, especially to children.

So far, nobody knows whether they do. But the questions are serious enough that several suburban cities have taken cautionary steps.

Renton, for example, three years ago adopted zoning rules prohibiting construction of buildings within a certain distance of the lines. Bellevue has started implementing its own new policies, which will include warnings to potential purchasers of homes near such lines.

And tomorrow in Renton, a regular meeting of planners from King County and suburban cities will focus on this topic - listening to national speakers discuss what's known and what's not.

What's NOT known still appears to be the largest category.

A 1979 Denver study linking transmission lines to increased leukemia risk in children, which was the beginning of concern in the United States, has been supported by later research.

Yet other studies have found no links between electromagnetic fields (EMF) and health, setting up contradictions, questions and differences in interpretation not likely to be ironed out for years. One theory speculates that tiny electrical signals from a magnetic field - either from a power line or household appliances - are amplified when they reach the surface of a cell in the body.

According to this theory, those signals trigger an electrical discharge that disrupts communication within and between cells and could lead to unregulated cell growth.

Electromagnetic fields are not generated only by big transmission lines. Anything that uses electricity, from residential power lines to home wiring to blow dryers, has one. Electrical fields are present all the time; magnetic fields only when current is running, when the light or television is turned on.

``It's a very, very complex mystery, really,'' said Scott Forslund, spokesman for Seattle City Light, which owns the 230,000-volt line that runs through the Eastside.

But such a mystery, when it's about a possible cancer risk, concerns people.

``Our concern, to be very frank, is one of public liability,'' said Don Erickson, Renton zoning administrator. ``If there's information out and we don't heed it, later on . . . we might be held liable. I've had people in the power industry tell me they got rid of their electric blankets a long time ago.''

About three years ago, Erickson said, Renton decided it should try to address the issue. The city required buildings to be located so that magnetic fields reaching them would be no stronger than 100 milligauss - the unit used to measure EMFs. That would mean, for example, that no building could be built closer than about 40 feet from a 230,000-volt line, Erickson said.

``Renton's in an unusual situation,'' said planner Mary Lynn Myer. ``Being at the end of the lake we're at a crossroads for many things. We have a number of transmission lines that come through Renton.''

So far, the standard has only been applied to a handful of permits, Erickson said, and other approaches are being considered.

Bellevue has also recently decided to address the EMF issue as part of its environmental-review process - applying it both to projects proposed near existing transmission lines and to proposals for new power lines themselves.

There aren't enough data either to recommend that such projects be denied, or to say that they are not hazardous and should be approved, said Ray Sachs, a Bellevue environmental planner.

``Realistically,'' Sachs said, ``I don't expect the research to reach any firm conclusions. We can't be ahead of science. It's not a simple issue of stay far enough away from it and you're safe.''

In some studies, people who were exposed to stronger fields had a lower incidence of health problems than those exposed to weaker fields.

The city wants to accomplish two things: lay out the debate for the City Council to help them make land-use decisions and attach warnings about potential risk for potential homeowners.

So far, three proposed projects will likely be affected, Sachs says. The first is a new 115,000-volt line Puget Power has for the past decade wanted to run from Factoria into Bellevue's downtown. An environmental review is under way, Sachs said. No hearings are scheduled.

The other two are proposals close to 124th Avenue Northeast, where the Bothell-to-Maple Valley transmission line runs: a request to divide one parcel into five for a housing project and a rezone request to allow four houses on one large lot.

``What we would probably do,'' Sachs says, ``is to condition a project like that so there was some kind of language to alert potential homebuyers to that situation: That it is an unresolved issue but there may be some risk.''

Anybody buying a parcel within that subdivision would be warned about that on official documents, including title reports.

The same condition would probably not be added to new apartments or businesses near power lines, Sachs says, because the city would have no way to force owners to provide warnings to renters or employees.

Renton and Bellevue aren't the only communities starting to grapple with the issue.

-- Just last week near Mill Creek, for instance, parents petitioned the Everett School District not to build an elementary school near some 120,000-volt lines until more is known about the effect of EMF.

But the fact is, schools have been sitting for years in the shadow of power lines.

-- The Northshore School District plans to build an elementary school in Bothell 130 feet from the 230,000-volt line along 124th Avenue. Steve Young, director of district operations, called in Seattle City Light to take readings of the magnetic field.

In the two Denver studies that linked EMF to increased risk of leukemia in children, the fields were measured at about 2 milligauss in strength. A computer model of the readings for the Northshore school site ranged, Young says, from .27 to 1.3 milligauss - lower than in district buildings.

Still, Young says, building designers worked to reduce EMF fields in the proposed school where they could. They'll be using gas heat, for example, and ceilings will be high, keeping fluorescent lights farther from children's heads.

-- Evergreen Hospital Medical Center in Kirkland sited its brand-new hospice center near the same line and reported the same testing results. ``We found there was less radiation emitted from (the power lines) than from a television,'' said hospital spokesman Bud Wagner.

-- Despite such uncertainty about the hazards, some Bellevue residents who live along 124th Avenue have asked Seattle City Light for readings anyway. After getting those readings, one woman said her family decided to quit worrying until and unless they get a better reason to start again.

``I worried and worried about it. I talked to our pediatrician,'' said the woman, who did not want to be named. ``I've gotten the same response: There's a lot of worse things we can do for the kids.''

Information

on magnetic fields

Utilities will, upon request, send out literature and measure magnetic fields near homes. To contact utilities:

-- Seattle City Light - Julia Greenlee, 684-3726, or write to her at 1015 Third Ave., Seattle, WA 98104-1198.

-- Puget Power - Mel Walters, 462-3089.

-- Snohomish PUD - Ask for the Safety Department at 347-5555 or write: P.O. Box 1107, Everett, WA 98206.

-- Tacoma City Light - Call Community Services at 591-9759 or write: P.O. Box 11007, Tacoma, WA 98411.

-- The Bonneville Power Administration study and brochures on the issue are available from BPA's Seattle office, 553-4136, or P.O. Box C19030, Seattle, WA 98109-1030.