Total Reflection X Ray Fluorescence in environmental and geochemical studies: Unveiling Solute Source in Streams during a Rain Episode.

RODRIGUEZ CASTRO, CAROLINA; VILCHES CAROLINA.; TORREMORELL, A.; VÁZQUEZ, CRISTINA; GIORGI, ADONIS

X-RAY SPECTROMETRY

John Wiley and Sons

Año: 2016 vol. 45 p. 225 - 232

0049-8246

Rural population useswater for irrigation, animalwatering and for their own consumption, therefore water contamination is a major concern and a priority for its inhabitants. Unveiling the presence and source of contaminants can help to understand the dynamic of pollutants and therefore define management politics to address the issue. One way to elucidate the origin of contaminants in surface water is by studying rain episodes, relating water discharge with changes in solute concentration. Total Reflection x-ray Fluorescence (TXRF) was used as the main analytical technique. The study was based on the analysis of samplesoriginating froma Pampean stream(Buenos Aires, Argentina). Solutes (As, P, Ca, Fe, K, Zn, Br) weremonitored before, during and after a stormevent. During the monitoring it was observed that As was diluted at the beginning of the episode and concentration increased slowly after the rain ceased. The pattern of As is consistent with Ca, K and Fe behavior, revealing a groundwater source. Instead, P concentration increased in the early hours, it was diluted later and finally increased. This behavior indicates that the source of this analyte is superficial and sub superficial water, implying a runoff origin. The simultaneous determination of these analytes by TXRF allowed comparing solute behavior under the same episode, allowing reveal their provenance.