The Santa Cruz County Health Department and the sheriff's office, along with the U.S. Border Patrol have expressed concerns regarding incidental contact with the water in Nogales Wash, Arizona. The public has expressed significant concern about direct public exposure to waters flowing in the wash. The Arizona Department of Health Services completed this health consultation to evaluate the levels of organic and inorganic chemicals at the request of the Santa Cruz County Health Department.

The Arizona Department of Environmental Quality and the California Department of Toxic Substance Control worked together to assess background levels of naturally occurring metals in groundwater wells at Topock and Golden Shores, Arizona. The communities expressed concerns regarding the findings, thus the ADEQ requested the Arizona Department of Health Services to evaluate whether these naturally occurring metals in groundwater wells are present at levels that may cause adverse health effects.