Aqueous Arsenic Speciation with Hydrogeochemical Modeling and Correlation with Fluorine in Groundwater in a Semiarid Region of Mexico

Abstract

In arid and semiarid regions, groundwater becomes the main source to meet the drinking water needs of large cities, food production, and industrial activities. For this reason, necessary studies must be carried out to estimate its quantity and quality, always seeking sustainable management, thus avoiding social conflicts or a decrease in the productive activities of humanity. This research explains the behavior of groundwater quality concerning arsenic speciation and its relationship with fluoride. The average total arsenic concentration of 19.95 µg/L and 20.29 µg/L is reported for the study period from 2015 to 2020, respectively, according to the Mexican standard. If the population drinks water directly, it is exposed to possible damage to health. The predominant arsenic species is As (V), with 95% and As (III) with 5%, this finding will allow us to define in greater detail the type of remediation that is required to reduce the content of this element in the water. Regarding the relationship between arsenic and fluorine, very small Pearson correlation coefficients of the order of 0.3241 and 0.3186 were found. The estimation of the space–time variation made it possible to identify the areas with the highest concentration of arsenic and fluorine, allowing the definition of the operating policies of these wells, thereby protecting the health of the inhabitants who consume this water.

Spatial distribution and chemical speciation of some potentially toxic elements in Qena Governorate groundwater, Egypt

“…The dominant form of As was HAsO4 -2 owing to the high pH value (>6.9) of the studied groundwater. The prevailing of this As +5 forms has good implication for the As elimination from water [55].…”

Upward Trends and Lithological and Climatic Controls of Groundwater Arsenic, Fluoride, and Nitrate in Central Mexico

“…The state of Zacatecas contains 34 alluvial aquifers; 25 of them are endorheic basins that belong to a group called Cuencas Centrales del Norte, and nine that belong to Cuencas Rio Lerma y Santiago and discharge into the Pacific Ocean [34,35]. Large groundwater withdrawals from aquifers surrounding the city of Zacatecas (e.g., Calera, Aguanaval, Chupaderos) for urban, agricultural, and industrial purposes have caused depletion of groundwater levels and altered groundwater flows [5,20,26,[36][37][38][39].…”

“…The values and distribution pattern have been commonly related to not only the mineral composition of the aquifer but also to the alkalinity and hydrothermal conditions. Studies are now encompassing hydrogeochemical enriching processes, among them evaporation, residence time, presence of other ions, and mixing with contaminated flows from mining or agricultural activities [10,[26][27][28]. In Zacatecas (Central Mexico), groundwater is the primary source of water for drinking, agricultural, and industrial purposes.…”

Probabilistic Risk Assessment of Exposure to Fluoride in Drinking Water in Victoria de Durango, Mexico

“…Despite the abundance of studies on fluoride concentration levels in Mexico and specifically in Durango [3,4,22,23,25], much of the attention has focused on the potential health threat, especially in children, through deterministic approaches and epidemiological studies focused on specific population groups [16,20,21,26]. However, there is a marked shortage of information regarding health risk analysis from a probabilistic perspective, particularly in the adult population, and substantial knowledge about skeletal fluorosis in adults is absent.…”