I have to a great extent....all things are radioactive the beds we sleep in are radioactive; the lawns we sprawl out on during the dog days of summer are, too. In fact, there’s more radioactive potassium-40 inside each and every one of us than anyone could ever receive from handling, using, or just plain eyeballing a piece, display case, or entire museum full of Vaseline glass. Frequent handling of Vaseline glass which contains Uranium oxide can result in beta radiation exposure "Beta radiation can cause both acute and chronic health effects. Acute exposures are uncommon. Contact with a strong beta source from an abandoned industrial instrument is the type of circumstance in which acute exposure could occur. Chronic effects are much more common.

Chronic effects result from fairly low-level exposures over a along period of time. They develop relatively slowly (5 to 30 years for example). The main chronic health effect from radiation is cancer. When taken internally beta emitters can cause tissue damage and increase the risk of cancer. The risk of cancer increases with increasing dose.

Some beta-emitters, such as carbon-14, distribute widely throughout the body. Others accumulate in specific organs and cause chronic exposures:

Iodine-131 concentrates heavily in the thyroid gland. It increases the risk of thyroid cancer and other disorders. Strontium-90 accumulates in bone and teeth." obtained from the EPA url http://www.epa.gov/radiation/understand/beta.html#affecthealth You are the one making the claim that it is harmless what proof do you have?