Hydrogeochemical Processes and Potential Exposure Risk of Arsenic-Rich Groundwater from Huaihe River Plain, China

Muhammad

et al. 2022

Front. Environ. Sci.

Arsenic is considered a poison because of its seriously toxic effects on the human body; elevated concentrations of arsenic in drinking water have been reported in different parts of the world. Investigating the arsenic distributions in soil, surface water (SW), and groundwater (GW) is an interesting topic of research, along with probing its correlations with local factors of the ecosystem and other hydrogeochemical parameters. This study mainly aims to investigate the impacts of various factors on elevated arsenic concentrations in water and soil. The following factors are assessed for their relationship to the propagation of arsenic in Jianghan Plain, which is the study area: population density, pumping rate, rain, land use, surface elevation, water level, and heavy metal contamination. The arsenic contamination potential prediction map and categories were developed using GIS-based techniques, such as ordinary kriging and quantile methods. Then, the “raster calculator” tool was applied to verify the impacts of the abovementioned factors on arsenic concentration. Eighty-four single-factor, bi-factor, and multi-factor models were established to investigate the effective combinations among the factors. Land use and pumping rate were identified from the soil through an equal frequency tool, whereas water population density and pumping rate were obtained with high matching percentages. The arsenic concentrations varied in the ranges of 0.0001–0.1582 mg/L in GW, 0.0003–0.05926 mg/L in SW, and 1.820–46.620 mg/kg in soil sediment. The single factors showed the best equal frequency of arsenic concentration in water for population density (68.62%) and in soil for land use (65.57%) and pumping (63.66%). Statistical calculations with percentage frequency factors also depicted a positive trend. Arsenic was reported to have high correlations with Fe in GW (r2 = 0.4193), with EC in SW (r2 = 0.4817), and with Cu in soil (r2 = 0.623). It is observed that the alkaline behaviors of water bodies are associated with arsenic mobility. Elevated arsenic values were observed in grids along surface flows with high anthropogenic activities and urbanization. Additionally, low concentrations of Fe depicted reduced activities in aquifer systems. Filtering drinking water as well as controlling the suspected sources and factors affecting concentrations of arsenic in the three phases are options for reducing the health risks of the local populations.

Section: High Equal Frequency Factors In Water Bodiesmentioning

confidence: 99%

Spatial distribution and risk identification of arsenic contamination in water and soil through GIS-based interpolation techniques in Jianghan Plain, Central China

Muhammad

et al. 2022

Front. Environ. Sci.

“…The formation of arsenic-bearing groundwater is the result of a series of water-rock interactions, hydrogeochemistry and geological microorganisms. The release mechanisms are mainly as follows: desorption, reductive dissolution of arsenic-bearing minerals, oxidation of arsenic-bearing minerals and the direct reduction of arsenic [17][18][19][20][21][22]. There are mainly two forms of arsenic in nature, inorganic arsenic and organic arsenic, and its main valence states are As 3+ and As 5+ .…”

Section: Introductionmentioning

confidence: 99%

Microbial Community Structure of Arsenic-Bearing Groundwater Environment in the Riverbank Filtration Zone

Lü

Yang

Yin

et al. 2022

Water

Arsenic (As) contamination of groundwater is a global public health problem. Microorganisms have a great effect on the migration and transformation of arsenic. Studying the effect of microbial community structure and function on arsenic release in the groundwater environment of the riverbank filtration zone has important theoretical and practical significance. In this paper, in-situ monitoring technology and molecular biology technology were used to study the microbial community in the process of river water infiltration in the Shenyang Huangjia water source, China. The results showed that the structure, diversity and abundance of the microbial community in groundwater were closely related to the arsenic content. Proteobacteria was the dominant phylum in groundwater of the study area, and Acinetobacter, Pseudomonas, Sulfuritalea, Sphingomonas and Hydrogenophaga etc. were the main dominant bacterial genera. In addition to reducing and oxidizing arsenic, these functional microorganisms also actively participated in the biogeochemical cycle of elements such as iron, manganese, nitrogen and sulfur. There was a significant correlation between dominant bacteria and environmental factors. Fe/Mn had a significant positive correlation with As, which brought potential danger to the water supply in high iron and manganese areas.

“…In China, more than 19 million people are exposed to arsenic-rich water (Xu et al, 2022). Thus, it is urgent to remediate the arsenic-contaminated water by effective methods.…”

Section: Introductionmentioning

confidence: 99%

Phytoremediation potential of Acorus calamus L., an emergent macrophyte, to remove inorganic arsenic from water

Li¹,

Zhang²

2022

Preprint

In this study, the emergent macrophyte Acorus calamus L. was used to remove different concentrations (200, 500, and 1,000 µg L‒1) of arsenate [As(V)] and arsenite [As(III)] from water. The removal efficiencies of As(V) and As(III) reached more than 95%. As(III) could be removed by A. calamus L. more efficiently than As(V). In both As(V)- and As(III)-exposed A. calamus L., the arsenic contents were much higher in the root than in the stem and leaf. The translocation factors of As(V) and As(III) were no more than 0.152. Both As(V) and As(III) were found in the whole plant, whereas dimethylarsinic acid (DMA, 0.06‒0.13 mg kg‒1) was only present in the aboveground part (leaf). As(V) was the main species in the As(V)-exposed plants (45.86%‒70.21%). As(III) was the main species in the stem and leaf of As(III)-exposed plants (55.76%‒85.52%), while As(V) was still dominant in the root. A. calamus L. could keep its green leaves during the 31 days of inorganic arsenic (iAs) exposure. However, As(V) had a little inhibitory effect on height growth, and As(III) could slightly inhibit the weight gain. The concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2), as well as the activity of catalase (CAT) were significantly higher in the root than those in the stem and leaf. The oxidative stress response of A. calamus L. to As(III) was more than that to As(V). Our findings indicated that A. calamus L. was regarded as a promising material for the removal of iAs.