Mill Creek parents worry about health risks from planned power line

Columbia Missourian

COLUMBIA — Some Columbia residents fear that a proposed electric transmission line for south Columbia could emit harmful electromagnetic fields that could be bad for the health of their children.

The Columbia City Council approved the route for the 161-kilovolt transmission line in 2013 in order to boost electric capacity and reliability in south Columbia and to meet federal regulations, according to the city website. The new power line circuit, which is planned for construction in 2017, will run from the Mill Creek substation along Providence Road, Grindstone Parkway, Nifong Boulevard, Vawter School Road and Scott Boulevard.

The route would lead the line near Mill Creek Elementary School and homes where some residents say they will be exposed to electromagnetic radiation from the power lines.

"We are concerned because we believe the public and various stakeholders might be underinformed about the possible health concerns," resident Detelina Marinova, who is a parent of a Mill Creek Elementary student. "More specifically, the adverse health concerns from EMFs generated by the high-voltage power lines."

What are EMFs?

EMFs, or electromagnetic fields, are a "combination of electric and magnetic fields of energy that surround any electrical device that is plugged in and turned on," according to the Environmental Protection Agency website. This includes things such as power lines but also household items such as microwaves or cellphones. EMFs are measured in milligauss or microtesla — milligauss can be divided by 10 to convert to microtesla.

Are EMFs harmful? 

Multiple studies have been done on whether electromagnetic fields are linked to an increase in childhood leukemia. Marinova said no studies have been able to disprove this link.

"There's been hundreds and hundreds of studies, and many of them find the type of positive effects (that EMFs are linked to leukemia)," said Marinova, who has a master's degree in statistics. She also noted that some studies show no statistical relationship but said those don't indicate absence of influence from industry or special interest groups.

Narrowing down exposure from EMFs is difficult because so many devices emit them, Columbia Water and Light spokeswoman Connie Kacprowicz said.

"As I sit here right now, I'm surrounded by a computer monitor. Next to me is an iPad and an iPhone, and my back is really hurting, so I've got a heating pad on," Kacprowicz said. "I am, right now at my desk, being exposed to EMF. So, if there were a transmission line outside my window, it's hard to get to the point where you are saying there's a direct cause-and-effect from one thing."

Marinova, however, said the EMFs emitted by power lines don't compare to household electronics.

"Length of exposure matters in terms of EMF and adverse health effects," Marinova said. "You use your phone intermittently, whereas the power line (has) a constant nonstop exposure," Marinova said. "So think about it: These elementary kids would be exposed to it for six years, every school day, for eight hours. ... Using the microwaves for two minutes is not even close."

Kacprowicz said researchers haven't consistently found that EMFs are bad for people's health.

"One scientist might come up with a conclusion, and another scientist tries to duplicate that conclusion and can't come up with the same results," Kacprowicz said, noting that the National Institutes of Health have found no direct link.

The city held an open house Wednesday to discuss the power line project with residents. It also presented a packet of 2002 information from the National Institute of Environmental Health Sciences about the health risks associated with EMFs.

According to the packet, there is "still no definitive answer" to whether EMFs are linked to childhood leukemia.

The British Journal of Cancer published a 2000 "pooled analysis of magnetic fields and childhood leukaemia." It combined findings from different independent studies on EMFs to reconcile differences and eliminate outliers.

This meta-analysis found that children who had residential exposure to more than 0.4 microtesla of EMFs — who comprised only 0.8 percent of the children in their study — had twice the risk of leukemia than the 99.2 percent of children studied who were exposed to less than 0.4 microtesla of EMFs. The authors said that was "unlikely to be due to random variability."

"The explanation for the elevated risk is unknown, but the selection bias may have accounted for some of the increase,"  the authors concluded.

How strong of an EMF would the new power line emit?

EMFs vary depending on how close someone is to the object emitting them, which is one reason power lines are so tall, Kacprowicz said. Dan Clark, electric engineering supervisor for the city, measured 0.55 microtesla of EMFs beneath a 161-kilovolt line Tuesday.

"The magnetic field strength is a function of how much current is on a conductor and how close you are to the conductor," Clark said in an email. "So, a conductor with high current that is pretty far away from you may have the same magnetic field as a (conductor) with a small current that is up close to you."

Kacprowicz said Clark measured EMFs from the power line at about 300 feet away, which is about how close Mill Creek Elementary would be to the new line. The readings dropped to 0.01 microtesla. Those readings were also presented at the Wednesday open house.

Marinova said the city wasn't clear in the beginning how strong of an EMF the line would emit or whether there might be health risks.

Clark said that until the new line is installed, it will be difficult to know what readings it might create.

"The amps on a transmission line constantly vary depending on system conditions," Clark said, "and the distance of the conductor above the ground constantly varies depending on where (you) are in the span."

What's next?

The council, when it approved the power line project, decided none of the new lines would be buried. Kacprowicz said that would be only an aesthetic benefit but would cost about $4 million more per mile than putting lines overhead.

Second Ward Councilman Michael Trapp defended the council's route choice. "The lines need to run by somebody's house, and there's huge benefits to having electricity, and there are unquantifiable risks about transmission lines."

Marinova and other parents are asking the city to honor a resolution drafted by the Columbia Council of Parent Teacher Associations, which comprises all PTAs in Columbia. It calls on the city to bury high-voltage power lines near schools and to set them back at least 300 feet from school property lines. If that's impossible, the resolution says "all efforts be made to reduce the emissions of electromagnetic fields to a minimum including the installation of gas or liquid-filled, pipe-type systems."

Clark said there's no way to get away from EMFs.

"EMFs exist whenever and wherever electricity is being used," Clark said. "They cannot be separated from electricity, just as the effects of gravity cannot be separated from an object that has mass."

Not all parents are as worried about EMFs.

"Am I concerned? Sure," Mill Creek Elementary parent David Townsend said. "There's always a concern when high power lines go anywhere near where kids are, not just for that (EMF) but in case of a storm. But they're everywhere right now, so it's nothing we can really ever get away from."

Trapp said the possible danger from EMFs doesn't match that of having no electricity.

"It's a huge blessing to be able to flip a switch and the light comes on," Trapp said. "That's nothing we can take for granted. There's billions of people that live around the planet without reliable electricity. Ask what they would think about the relative risks of EMF exposure versus the risks of not having reliable electrical service."

Clark agreed that living without electricity would pose more risks than EMFs.

"(Leukemia) is a terrible disease, but fortunately also very rare," Clark said. "If you did find a population of people that are voluntarily living without electricity, they would probably have other, more serious health problems."

Columbia resident Carolyn Hawks said at the open house that if there's a chance the power lines could cause leukemia, there's no reason to risk it.

"It’s one of those things that’s very hard to document, but if there’s the slightest risk, why would you go near schools? Or nursing homes? Or preschools?"

Kacprowicz said that while the city is seeking residents' feedback, it would take considerable effort to change the route of the line.

"We need to have this conversation with the public now, see what they think, what we can do as far as shifting it," Kacprowicz said.