The Arizona Department of Environmental Quality (ADEQ) requested the Arizona Department of Health Services to determine whether exposure to tetrachloroethylene (PCE) in the indoor air of a vacant dry cleaning facility and an attached convenience store posed a health threat to workers renovating the former dry cleaners and the patrons and employees of the convenience store. The former Viking Cleaners operated from 1954 until 2000. The building houses two businesses, Viking Cleaners, which is currently vacant but under renovation, and an attached convenience store that is currently in operation.

A refuse dump near Naco, Sonora, Mexico, caught fire and burned from December 1 to December 5, 2001. The fire, which consumed large quantities of household refuse, also generated a large quantity of smoke. During this period, considerable smoke was intermittently present in Naco, Arizona. This report summarizes the events that occurred during the fire and analyzes the data collected by the Arizona Department of Health Services and the Arizona Department of Environmental Quality to determine the extent of the public health threat from the fire.