The world needs a new source of energy, an unspillable source.

Is burning coal a source of radioactivity?

The U.S. Nuclear Regulatory Commission (www.nrc.gov) mentions that sources of radiation exposure are first and foremost due to things like radiation for cancer therapy. That makes sense. Then, it says that secondary sources of exposure are cigarette smoke (thorium) and burning coal!

Does anyone know what radioactive substance is present in coal? Perhaps there’s more than one common radioactive element in coal, and that’s why they listed the chemical in cigs but not in coal?

Thanks in advance!

-K
Perhaps I should state that the radioactivity from coal was listed as a *greater* risk than that of a nuclear power plant – being 50 miles or less away from a coal-burning electric plant was considered to be *more* dangerous than being 50 miles away from a nuclear power plant.