Measurement of Trace Heavy Metals and Inorganic Ions in Rains from Rancho Viejo, A Rural Wooded Area and from Southwest Site of Mexico City

摘要

Measurements of the trace metals Al, Cd, Cr, Mn, Ni, Pb, and V in soluble and insoluble rain fractions and SCV" NO3", Cl", Ca Mg , Na"*, K*,NH/ and H+ in soluble fractions, were performed in rain water collected at Rancho Viejo (RV), a wooded rural area in the state of Mexico and at the southwestpart of Mexico city (CU), during the rainy seasons of 2001 and 2002. In both sampling sites, aluminum presented the highest volume-weighted meanconcentration (VWMC), in total (soluble and insoluble) fractions. Ammonium presented the higher VWMC and was the main neutralizing ion. Air mass backtrajectories in Mexico City were associated to the concentrations of trace metais, ions and H+ observed {luring the rainy day But trace metals concentrationswere not clearly related to wind directions The high enrichment factors (EFc) were calculated related to the relative abundance of elements in crustal materialsFactor Statistical Analysis 6.4 was applied to all data, to have a better knowledge of trace metals in rainwater. Pearson's correlations show that Al correlatedwith most of the metals; Al presented the highest wet deposition flux.