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Concern for heavy metal ion water pollution
Published in Manish Kumar, Sanjeeb Mohapatra, Kishor Acharya, Contaminants of Emerging Concerns and Reigning Removal Technologies, 2022
Sasireka Velusamy, Anurag Roy, Senthilarasu Sundaram, Tapas K. Mallick
Arsenic is a naturally occurring metalloid that exists in organic and inorganic forms in water sources. Thermodynamically, arsenic (As) has four stable oxidation states: +5 (arsenate), +3 (arsenite), 0 (arsenic), and –3 (arsine). As compounds from industrial effluents can easily dissolve in water and contaminate water resources like lakes, rivers, and groundwater by dissolving in rain and snowfall. Therefore, arsenic contamination of groundwater is a severe health threat worldwide. According to USEPA, the permissible limit of the arsenic ion is 0.05 mg/L (Gautam et al., 2016). The WHO has also set the guidelines to maintain all the metal ions, particularly arsenic. The WHO decreased their recommendation from 0.05 to 0.01 mg/L to protect our health from arsenic contamination. The groundwater can contain high arsenic concentration that should be tested to carefully identify the arsenic contamination level. It has to be monitored to avoid the perplexity of arsenic-containing water consumption. In general, the arsenic concentration in the Earth’s coating ranges from 1.5 to 5 mg/kg; higher concentrations found in sedimentary rock, mainly in iron and manganese ores. Arsenic released from these ores enters the soil, surface water, groundwater, and other possible sites.
Emergence and evolution of groundwater management and governance
Published in Karen G. Villholth, Elena López-Gunn, Kirstin I. Conti, Alberto Garrido, Jac van der Gun, Advances in Groundwater Governance, 2017
Marco García, Ebel Smidt, Jacobus J. de Vries
Arsenic contamination of groundwater occurs where high natural concentrations of arsenic in deeper parts of the aquifers have been reached by excessive extraction and depletion. A recent example is the Indo-Gangetic Basin in India. Groundwater abstraction from the transboundary Indo-Gangetic Basin comprises 25% of the global groundwater withdrawals, sustaining agricultural productivity in Pakistan, India, Nepal and Bangladesh. Excessive abstraction has meanwhile caused 60% of the aquifer to become unsuitable for drinking purposes due to high levels of salinity and arsenic (MacDonald et al., 2016).
The Story and Future of Nanoparticulated Iron Materials
Published in Marta I. Litter, Natalia Quici, Martín Meichtry, Iron Nanomaterials for Water and Soil Treatment, 2018
In recent years, a range of inexpensive, iron-based, water cleanup technologies have been developed to address the major problemof arsenic contamination in groundwater used for drinking [51]. Quinn et al. [75] highlighted the potential of nZVI to treat dissolved chlorinated solvents in situ, and to remediate zones with DNAPLs in aquifers. Since then, several field experiments were developed, typically injecting nanoparticles directly as a slurry (nanofluid) into the subsurface environment (e.g., [5, 26, 76]). The first field injection test of nZVI was reported in 2001 [26] for in situ degradation of chlorinated organics in groundwater. When a non-stabilized nZVI suspension was injected into the subsurface, it was observed that nZVI aggregates rapidly deposited on the well screen, while the remaining finer nZVI could travel from a few inches to a few feet before becoming immobilized in the soil matrix. The trend was then to investigate more effective stabilization techniques and more deliverable nZVI. The utility of iron nanoparticles in removing or stabilizing metallic and metalloid contaminants has also been demonstrated in a variety of soil and water media. Examples of reducing As [77, 78], Cu(II) [79], and Cr(VI) [80] mobility in groundwater or soils have been reported. A rapid transfer of nanoiron-based remediation technologies from laboratory to field-scale application and full-scale commercial applications of nZVI in land and groundwater remediation have rapidly developed [3]. In 2009, the technology was tested at the pilot- or field-scale at more than 58 sites [81], which increased to around 70 projects worldwide at the pilot or full scale in 2015 [82, 83]. Various remediation efficiencies have been observed in field trials in the USA and in Europe [75, 8488].
Magnetite interaction with arsenic during sorptive removal from groundwater: a mechanistic study
Published in Journal of Environmental Science and Health, Part A, 2023
Nicy Ajith, A. K. Satpati, A. K. Debnath, Kallola K. Swain
Arsenic is a metalloid and the presence of this in natural water and soil leads to global problem of arsenic contamination in groundwater. Due to the result of natural and man-made activities, the arsenic from the arseno-pyrite layer gets leached and enters into groundwater system.[1,2] Arsenic is notorious for its carcinogenicity and related serious health hazards.[3] The value of arsenic in water should be preferentially zero, but since it is mainly originated from the natural source and hence cannot be completely nullified. In such a scenario, WHO had set the maximum permissible limit for total As as <10 µg L−1 in potable water. Researchers had put their intense research work in this area for achieving the arsenic value below WHO limit.
Geo-spatial distribution of arsenic contamination of groundwater resources in intricate crystalline aquifer system of Central India: Arsenic toxicity manifestation and health risk assessment
Published in Human and Ecological Risk Assessment: An International Journal, 2021
Rambabu Singh, Anadi Gayen, Suresh Kumar, R. Dewangan
Unlike the other regions in which the arsenic occurs in strongly reducing aquifers often derived from alluvium, flood plains, deltas, and river basins; the arsenic contamination in groundwater of the current study area occurs in complex hard rock terrain in a sporadic manner, where oxidation of sulfide minerals in the host rock is the prime governing process (Mukherjee et al. 2019). Inhabitants from this area have been chronically exposed to arsenic contaminated drinking water through hand pumps, tube wells, and dug wells.