There are concerns and questions about radiation exposure in Japan because of problems at the nuclear power plant in northeast Japan.
Good Question: What are the risks and effects of radiation?
When it comes to radiation exposure, scientists say there is a simple rule, no amount of exposure is safe.
"Radiation is a very good at damaging DNA, which is the basic of how cells divide in our body," said Dr. David Brenner, Director of the Center for Radiological Research at Columbia University.
That damage can lead to cancer, which radiation expert Dr. David Brenner says is the biggest concern.
"The bigger the dose, the bigger the risk. The smaller the dose, the smaller the risk. And it doesn't happen overnight. Its typically 10, 15, 20 and 30 years after the exposure is when a cancer might appear," said Dr. Brenner.
We're all exposed to low levels of radiation everyday, it happens naturally in the soil water and air.
We get it when we fly or get an x-ray.
"There's no question that radiation produces cancer, there are certainly still debates going on at very low does of radiation do they not," said Dr. Brenner.
As for our risk of exposure from what's happening in Japan, the head of the Nuclear Regulatory Commission says it is very unlikely that we will fee any harmful effects here in the United States.
Experts say so far the radiation released in Japan is nowhere near the level of the nuclear disaster at Chernobyl nearly 25 years ago.