Behavior from lead, niquel and vanadium contamination in Conchos River watershed

Abstract

A worldwide water deficit caused by increasing human population has generated a very high interest for this natural resource. To make a bad situation worse widespread contamination of water resources especially in the rivers has also become a serious concern for people on this planet. The Conchos watershed the most important in the State of Chihuahua because it is the sole source of water for more than 1,000,000 inhabitants living along its 560 km length. The objective of this study is to quantify the spatial and temporal contamination of Conchos River Water by the elements Lead, Nickel and Vanadium. Six sites were selected for bimonthly water sampling during 2004, from February to December. Two sites were selected in the upstream region of the watershed, 3 in the middle region and 1 about 1 kilometer before its confluence with the Rio Bravo. One liter of water was taken at each site, which was analyzed later for the metals (Lead Niquel and Vanadium) by the Inducted Coupled Plasma Spectrometer (ICP) technique. Multivariate statistical analysis showed that the highest levels of contamination occurred from the months of June to October. There are no differences between sites; however the most contaminated site was near Ojinaga City in the lowest region of the watershed. Increase levels of contaminants that sometimes are above recommended levels in Mexico are caused by the contaminant sources up river and by local human activities and the differences in time are related to rainfall with highest levels during the rainy season.