Evaluation of Long-Term (1960-2010) Groundwater Fluoride Contamination in Texas

Abstract

Groundwater quality degradation is a major threat to sustainable development in Texas. The aim of this study was to elucidate spatiotemporal patterns of groundwater fluoride (F) contamination in different water use classes in 16 groundwater management areas in Texas between 1960 and 2010. Groundwater F concentration data were obtained from the Texas Water Development Board and aggregated over a decadal scale. Our results indicate that observations exceeding the drinking water quality threshold of World Health Organization (1.5 mg F L) and secondary maximum contaminant level (SMCL) (2 mg F L) of the USEPA increased from 26 and 19% in the 1960s to 37 and 23%, respectively, in the 2000s. In the 2000s, F observations > SMCL among different water use classes followed the order: irrigation (39%) > domestic (20%) > public supply (17%). Extent and mode of interaction between F and other water quality parameters varied regionally. In western Texas, high F concentrations were prevalent at shallower depths (<50 m) and were positively correlated with bicarbonate (HCO) and sulfate anions. In contrast, in southern and southeastern Texas, higher F concentrations occurred at greater depths (>50 m) and were correlated with HCO and chloride anions. A spatial pattern has become apparent marked by "excess" F in western Texas groundwaters as compared with "inadequate" F contents in rest of the state. Groundwater F contamination in western Texas was largely influenced by groundwater mixing and evaporative enrichment as compared with water-rock interaction and mineral dissolution in the rest of the state.

Hydrogeochemical Evaluation of Groundwater Quality Parameters for Ogallala Aquifer in the Southern High Plains Region, USA

“…Fluoride is an inorganic, naturally and anthropogenically occurring ion that is found along the natural surface and in groundwater [ 33 , 34 ]. Fluoride can originate from the dissolution of fluorite, fluoropatite, and certain silicates.…”

“…Mukherjee and Singh [ 35 ] confirmed this path of fluoride contamination, as the dissolution of fluorapatite by Pseudomonas fluorescens contributes to fluoride in the environment. Fluoride can have beneficial effects when taken in moderation, such as improving dental health and bone mineralization [ 29 , 33 ]. Drinking water is the primary pathway for intake and exposure to elevated levels of fluoride [ 34 ].…”

Water for All (Har Ghar Jal): Rural Water Supply Services (RWSS) in India (2013–2018), Challenges and Opportunities

“…The extent of spatial heterogeneity in RWSS coverage was assessed by agglomerative hierarchical cluster analysis (HCA). Application of HCA is well documented in water resources assessment studies (Chaudhuri and Ale 2015; Chaudhuri and Roy 2017; Hadjisolomou et al 2018; Shrivaastava, Tandon, and Kumar 2015). In the present context, the governing idea was to ‘generalise’ states based on similarity (or dissimilarity) in RWSS coverage (for both 40 lpcd and 55 lpcd) so as to identify underlying zones (of high/low coverage).…”

“…An idea to use HCA was, elicit the regional differences in RWSS coverage, so as to identify a ‘zonal structure’, which could potentially be used by the authorities to spatially optimized interventions in days ahead. The HCA was performed by using Ward’s minimum variance algorithm (Chaudhuri and Ale 2015).…”

Hydrogeological Characterization and Statistical Analysis for Ogallala Aquifer in the Southern High Plains Region, USA

“…Fluoride is an inorganic, naturally and anthropogenically occurring ion that is found along the natural surface and in groundwater [33]. It can be naturally found in volcanic rocks and Precambrian rocks, where there are said to be significant concentrations [34].…”