Concentration of heavy metals in condensed atmospheric water vapor at three Mexican localities

Abstract

The condensation of water vapor is a very useful technique in mitigating the scarcity of water resources for human consumption; however, the quality of this water must meet the highest standards to avoid becoming a health hazard. The present study quantifies trace elements such as As, Ba, Cu, Cd, Cr, Fe, Hg, Mn, Pb, and Zn, as well as pH and electrical conductivity (EC), in condensed atmospheric water vapor at three localities in Mexico. Atmospheric water vapor was condensed with an atmospheric water generator prototype. A total of 108 samples were obtained from three survey sites over the course of two seasons (wet and dry) during day/night shifts. The concentration of heavy metals was analyzed using inductively coupled plasma mass spectrometry. The pH and EC parameters were measured with a potentiometer/conductometer. We found Pb, Fe, and Cd in 91.66, 58.33, and 33% of the samples, respectively, at concentrations exceeding those permitted by the World Health Organization (WHO) for water intended for human consumption. Both pH and EC were within the limits established by the Department of Water Affairs of Namibia. The concentrations of trace metals in condensed atmospheric water vapor samples were within the maximum permissible limits determined by WHO for most elements analyzed in this study.