New findings by a group of Colorado researchers indicates lightning could be the culprit in a number of unexplained fatal heart malfunctions in the outdoors in recent years, including some in the state's high mountains.
In an article published in the June 13 issue of Lancet, a highly regarded medical journal published weekly in London, the Colorado team proposed that lightning can kill without a visible sign of electrical current entering or leaving a person's body.
In most lightning fatalities, victims exhibit external damage such as skin burns where electrical currents have entered or exited the body, the scientists said. Some victims, however, show no sign of external burns, indicating they were not touched by the lightning itself. Biophysical calculations by the research team indicate that in such cases, intense magnetic fields resulting from the lightning may induce fatal electrical currents entirely within the body.
The researchers authoring the Lancet letter include Dr. Michael Cherington, a neurologist at St. Anthony Hospital in Denver, Professor Howard Wachtel of the University of Colorado at Boulder's electrical and computer engineering department and Dr. Phillip Yarnell, also a neurologist at St. Anthony Hospital. All are members of the Lightning Data Center research group that meets monthly in Denver to discuss the medical aspects of lightning and other electrical injuries and deaths.
Wachtel, who has spent much of his career researching the impact of electromagnetic fields on human health, said the results of the research are still speculative. "But our calculations indicate the magnetically induced currents within the body during a vulnerable cardiac period could be strong enough to disrupt and fibrillate the heart, possibly causing death."
The researchers also have speculated that in some fatal cases of "hiker
heart attacks" in Colorado's high country, lightning strikes near the victims
Contact: Howard Wachtel
University of Colorado at Boulder