(Portland, OR)  --  The Department of Environmental Quality and the Oregon Health Authority say the latest air-quality data show there continues to be a low risk of health problems for Portland residents.  Officials say both air and soil samples tested reveal no urgent public health risk.  Portland businesses Bullseye Glass and Uroboros are taking measures to stop the use of arsenic and cadmium in manufacturing, and officials say air concentrations of those toxic metals have since declined.