Assessment of fluoride contamination and distribution: a case study from a rural part of Andhra Pradesh, India

Abstract

In total, 123 groundwater samples were collected to evaluate the suitability for drinking purpose in a rural part of Andhra Pradesh, India. The groundwater is alkaline in nature and pH varying from 7.18 to 9.32 with a mean value of 8.36. The hydrogeochemical analysis reveals that the fluoride concentration varies from 0.4 to 5.8 mg/L with a mean of 1.98 mg/L. Higher fluoride concentration is found in west-central parts of Markapur region. The villagers have been exposed to the intake of high fluoride-bearing groundwater for the prolonged period and suffering from the deadly disease fluorosis. However, with respect to groundwater chemistry, the fluoride concentration is high in Na + -HCO 3 − -type groundwater and low in Ca 2+ -HCO 3 − -type groundwater in the Markapur region. Data plotted in Gibbs diagram show that all groundwater samples fall under rock weathering dominance group with a trend toward the evaporation dominance category. Therefore, rock-water interaction is the primary cause of elevated fluoride in the groundwater of the study region. Furthermore, a significant positive correlation exists between F − and pH, HCO 3 as well as negative correlation exists between Fand Ca 2+ and NO 3 − , which supports that the alkaline nature of water is the main cause for dissolving fluoride-bearing minerals.

Monitoring of groundwater quality for drinking purposes using the WQI method and its health implications around inactive mines in Vemula-Vempalli region, Kadapa District, South India

“…It is clear that potential hydrogen is one of the causes to be found higher fluoride in the study area, while some samples in the study may have low fluoride concentrations because the study area under the part of the semiarid environment and solubility process of F − in groundwater vary from one rock formation to another. If pressure and temperature was under normal conditions, fluoride-bearing minerals have been sparingly soluble in water; under certain physicochemical conditions, dissolution processes are too fast (Prajapati et al 2017;Adimalla et al 2019d;Vikas et al 2009;Adimalla 2020c). In the semiarid region, soil plays a major role in weathering and aqueous leaching processes that determine the amount of F − in groundwater.…”

“…According to this piper diagram, groundwater of this study group is six types. (I) Ca 2+ -HCO 3 − , (II) Na + -Cl − , (III) mixed Ca 2+ -Na + -HCO 3 − ,(IV) mixed Ca 2+ -Mg 2+ -Cl − , (V) Ca 2+ -Cl − , and (VI) Na + -HCO 3 − (Adimalla et al 2019d). From the diamond-shaped triangular diagram, 57% of the samples belong to Ca-Mg-HCO 3 type and remaining 42% of the samples belong to mixed Ca-Mg-Cl type reveals that carbonate rock dissolution processes dominate in the groundwater of this region, and from cation triangle zone it is clear that 50% of the sample falls in no dominant zone; another 50% samples fall in magnesium dominant zone; from triangle anionic zone, 65% of the samples fall in bicarbonate zone and 25% samples fall in no dominance zone remaining samples fall in sulfate zone (Fig.…”

Estimation of uranium in groundwater and assessment of age-dependent radiation dose in Nalbari district of Assam, India

“…Problems like blue baby disease or methemoglobinemia can be caused by a nitrate content of more than 45 mg/L [16]. Diseases like dental and skeletal fluorosis can be caused by fluoride concentration of 3 mg/L or more [17].…”

Investigation of Groundwater Contamination and Health Implications in a Typical Semiarid Basin of North China

“…Groundwater is characterized by extremely low flow rate, with a mean residence time of 1500 years in the aquifers [8]. During the long residence time, it has sufficient time to interact with the surrounding media of the aquifers [9,10], and harmful elements such as fluoride, arsenic, and other toxic elements can become dissolved [11][12][13][14]. In addition, many external elements in groundwater have been shown to be elevated in recent decades in many regions around the world [15][16][17][18][19][20].…”