Radiation exposure explained

By Dr. Ananya Mandal, MDMar 14 2011

Amidst threat of major nuclear accident in Japan, people are in a state of panic worldwide said Jerrold Bushberg, a medical physicist at UC Davis. Bushberg said Americans do not have a good knowledge of the science of radiation and tend to over-exaggerate the risks.

Debates over the safety of exposure from radiofrequency waves emitted by cellphones and high-power lines is an example of how worried people are, he said. He added, “I think anything that has radiation associated with it conjures up in people’s mind - either consciously or subconsciously - fears of everything from nuclear weapons and nuclear reactor accidents like Chernoybyl…As children you get this message that radiation can do odd and mysterious things -- most of it not good.”

Chief health and medical editor Dr. Richard Besser discussed some potential hazards of radiation in this scenario. He pointed out that radiations are found naturally and nearly everywhere in the environment. Heat, light and microwaves all emit some form of radiation. Uranium, thorium and radium that emit radiation are found naturally in the earth's soil. This type of exposure is generally not considered a health concern. We are, at all times exposed to little radiation says the Centers for Disease Control and Prevention and 80% of this comes from natural sources and the remaining 20 percent comes from man-made radiation sources, mainly medical x-rays. Overall, scientists do not find our everyday exposures harmful.

However during a nuclear explosion like in Japan now, people are overexposed to high amounts of radiation over a short period of time and may develop acute radiation syndrome (ARS). Within the first few hours of exposure, people with ARS may experience nausea, vomiting, diarrhea, and skin damage. Over time, the radiation can damage a person's bone marrow and cause internal bleeding and other infections. Most people who do not recover from ARS will die within several months of exposure. Emergency evacuation during a radiation fall out should be in place.

For facts on radiation exposure and ways to protect yourself from radiation emergencies, visit the Centers for Disease Control and Prevention or the United States Nuclear Regulatory Commission.