Particles from outer space cause nuclear reactions in earth's atmosphere that make air slightly radioactive.

Since 2006 there has been a leak of 0.5 up to 2 liters slightly radioactive water from a deactivation-bath.

Surviving prints are slightly radioactive, a property which serves as a means of non-destructively identifying them.

Because this phosphogypsum is slightly radioactive, its use is banned in nearly every situation.

Its thermal baths was developed around the slightly radioactive and carbonic acid waters discovered in 1928.

This paint has thorium oxide in it and it's slightly radioactive.

Next to the spring with slightly radioactive water lies a small chapel from 1689.

The steam was slightly radioactive, regulators said, but was not a long-term contamination threat to the building.

One of the cars contained 190 pounds of slightly radioactive material which was consumed by the fire.

The coolant becomes slightly radioactive through the normal operation of a nuclear reactor.