1997k-219 adverseeffects air airpollution airqualitymanagement alpharays cancer congresses economicaspects environmentalaspects epidemiology governmentpolicy healthandhygiene healthaspects healthriskassessment indoor indoorairpollution lawandlegislation lungs microbiology neoplasms organiccompounds probability radiation-induced radiationcarcinogenesis radiationeffects radioactive radioactivefallout radioactivehazardrelease radioactivepollutants radioisotopesinthebody radiotherapy risk riskassessment riskfactors schoolbuildings students unitedstates wn300b872i1990 wn620n2746i1997