Arsenic in geothermal sources at the north-central Andean region of Ecuador: concentrations and mechanisms of mobility

作者：Cumbal Luis^*; Vallejo Paulina; Rodriguez Brigida; Lopez Dina

来源：Environmental Earth Sciences, 2010, 61(2): 299-310.

DOI：10.1007/s12665-009-0343-7

• Arsenic
• Geothermal
• Spring
• Sediment
• Ecuador

The arsenic content of geothermal hot springs and their sediments in the north-central Andean region of Ecuador has been investigated. The area of study is located between parallels 1A degrees 11'N and 1A degrees 30'S and includes five provinces. The area is rich in geothermal surface manifestations that are mainly used for medicinal baths in recreational complexes. Unfortunately, water residuals without treatment are released from the recreational facilities to surrounding water bodies. The results indicate that total arsenic in geothermal waters in this region has a range of 2-969 A mu g As/L, and sediments contain arsenic ranging from 1.6 to 717.6 mg/kg. Chemical analyses of sediment samples show the presence of sulfur, iron, aluminum and calcium. A high concentration of natural organic matter was also found in some samples (20-29.5%); thus sorption and coprecipitation can be the main mechanisms of As immobilization on mineral phases and natural organic matter.

• 出版日期2010-7