EMFs make the public nervous also because they are present everywhere. They
are generated by home appliances such as microwave ovens, personal computers,
hair dryers, and electric blankets. The public is not reassured by the fact
that scientists disagree on whether EMFs are an invisible threat to health.
In May 1995, the American Physical Society issued a statement that its review of the scientific literature found "no consistent, significant link between cancer and power line fields." But there are still questions to be resolved because of evidence of subtle effects of EMFs on cell membranes, and ORNL physicists and biologists have been grappling with these questions for several years.
Because of insufficient evidence to link EMF bioeffects with measurable
health effects, DOE has established four national facilities that will
determine if previously observed biological effects of EMFs can be reproduced
consistently. One such facility is now operating in Oak Ridge. On June 9, 1995,
ORNL's Electromagnetic Fields Bioeffects Laboratory was dedicated.
David Reichle (left), Paul Gailey, and Guy Griffin examine ORNL's Electromagnetic Fields Bioeffects Laboratory.
The theory that EMFs cause biological effects such as cancer is controversial for three reasons, says Gailey, a physicist.
"First, some epidemiological studies of various populations, beginning with a study in 1979, have shown a trend toward a higher incidence of cancer for people living near power lines," he notes. "But this correlation has not always been observed in studies of exposed populations.
"Second, no physical mechanism has been proposed to adequately explain reactions of biological tissue to weak electromagnetic fields in the environment. A theoretical problem is sorting out the effects of these environmental EMFs from the influence of the body's own electrical fields from nerve signals and background noise from the earth's geomagnetic field.
"Third, subtle EMF effects have been detected in cells such as changes in the flow of ions and increases in the proliferation of a line of cancer cells. But these effects have not been replicated consistently. That's why the government is supporting four EMF replication facilities."
The other three EMF bioeffects facilities are a Food and Drug Administration laboratory in Rockville, Maryland; a National Institute for Occupational Safety and Health laboratory in Cincinnati, Ohio; and DOE's Pacific Northwest Laboratory in Richland, Washington. The results of the experiments from these facilities will be used for a risk assessment to be completed by 1997 as mandated by the National Energy Policy Act of 1992. The assessment will be prepared by DOE and the National Institute of Environmental Health Sciences.
Startup funds for EMF research at ORNL came from an internal source: the Laboratory Directed Research and Development Fund. Later, DOE contributed $75,000 to purchase and install the EMF exposure system.
The facility consists of two exposure chambers, each containing a box for cell and tissue samples surrounded by a coil. When the coil is electrified, it produces an electromagnetic field. A computer operates the whole system, turning on one coil but not the other for each study. Researchers do not know which sample is exposed to the EMF until after the data are analyzed, preventing them from being biased in interpreting results. After they have analyzed the data, the computer tells them which of the two samples was exposed to EMFs.
The blind cell culture experiments at the facility are being conducted by biologist Guy Griffin of the Health Sciences Research Division; Gailey and Griffin will analyze the results. The first experiment used genetically engineered breast cells that emit light when exposed to estrogen-like compounds. The researchers searched for possible effects of EMFs on breast cells by measuring the cells' dim light emissions. The researchers will also try to replicate the results of a study that suggests that EMFs cause abnormal nerve cell growth.
Gailey says that many schools are built near power lines because land next
to power corridors tends to be inexpensive. Some worried parents, he adds, take
their children out of neighborhood schools near power lines and drive them
farther away to a different school. "The safety risk of driving the extra
distance each day is measurable," he says, "but the hypothetical health risks
of EMFs are not. The decision to change schools is difficult to justify based
on current scientific information."
Louise Dunlap, director of the Office of Science and Technology Partnerships, said the new facility will bring together technology transfer
functions into a central location that will enable the office to serve both its
internal and external customers more efficiently.
The Energy Research Laboratory Technology Applications Program, which is managed by Tom Rosseel through the partnership office, is a major resource for technology transfer programs at the Laboratory. In addition to cooperative research and development agreements (CRADAs), this program includes personnel exchanges, technology maturation, and technical assistance projects.
This program also provides funding and leadership for such broad efforts as the American Textile Initiative (AMTEX), a CRADA program involving the American textile industry and 10 DOE laboratories, including ORNL.
The user center program, which encompasses 11 facilities at ORNL and one at the Oak Ridge Y-12 Plant, attracts both academic and industrial users. About 300 universities and private firms have active user agreements.
The Minority and Small Business Office headed by Will Minter will also be
located in the new facility. This group informs small and minority businesses
of opportunities to work with ORNL staff and facilitates such interactions.
Johnson and her group were brought into the study when University of Colorado researchers found that the gene they were looking for was located in a region of a chromosome that has been extensively studied at ORNL since 1947. The ORNL studies had examined chromosomes from which small pieces had been knocked out, or "deleted," by exposure of mouse sperm to radiation.
"The gene we are looking for is located near the albino gene, a defective form of the gene that controls the amount of pigment in skin and hair," says Johnson. "Because the effect of having or not having the albino gene is obvious to the naked eye, it was one of the focal points of early genetics research at ORNL. As a result, we have mice with about 50 different deletions around the albino locus."
Traditional research into inheritance patterns concentrates on studying traits that are determined by a single genelike extra fingers. In these situations, if one parent carries the gene for extra fingers, a dominant gene, their child has one chance in two of having the trait. If both parents carry the gene, the child's chances of having extra fingers increase to three in four. In the case of a recessive gene like the one that causes cystic fibrosis, a child's chance of developing the disease is one in four if both parents carry the gene. If only one parent carries the gene, the child has one chance in four of becoming a carrier of the gene, but will not develop the disease.
Recently, computer-assisted analysis of genetic experiments has enabled researchers to digest the vast amounts of data necessary to study more complex traits, such as alcoholism, which are controlled by the interaction of several genes. The initial Colorado studies identified two lines of mice that differ dramatically in their physical reaction to alcohol. Known as "long-sleep" and "short-sleep," both groups of mice fall asleep when injected with ethanol (grain alcohol), but the long-sleep mice sleep 20 times as long as their short-sleep counterparts.
Unlike some of the other genes in the eight-gene group, such as the genes that control behaviors related to alcohol-water preference and alcohol withdrawal, the exact relationship of the long-sleep or short-sleep gene to an individual's tendency toward alcoholism has yet to be determined. "We can't tell which of these variations provides the good input and which provides the bad," says Johnson.
By breeding mice having selected deletions with long- and short-sleep mice, Johnson hopes to isolate the location of the gene more closely. For example, breeding a mouse with one of its sleep time control genes deleted entirely with a long-sleep mouse would result in half of the offspring being purebred long-sleep mice. On the other hand, if a long-sleep mouse were bred with a mouse having two intact sleep time control genes, then none of their offspring would exhibit the long-sleep reaction to alcohol. By breeding long-sleep or short-sleep mice with mice having deletions that come closer and closer to the suspected location of the gene, the boundaries of the gene can be fairly closely defined.
The gene is then copied, or "cloned," and analyzed by laboratory techniques to determine its structure and function. As a final proof, the cloned gene can be inserted into fertilized mouse embryos. If the mature mice that develop from these embryos exhibit the predicted long- or short-sleep reactions to alcohol, then the gene has been accurately identified.
Such a discovery would move science one step closer to understanding the
genetic bases of alcoholism in humans and help lay the foundation for research
into treatments for this condition.
[ Next article | Search | Mail | Review Home Page | ORNL Home Page ]