Human Health Risks due to Exposure to Water Pollution: A Review

Li P., Sabarathinam C., Elumalai V.

The processes of Fe(III) activated persulfate (PS) and H2O2 modified by catechin (CAT) had been shown to be effective in degrading contaminants. In this study, the performance, mechanism, degradation pathways and products toxicity of PS (Fe(III)/PS/CAT) and H2O2 (Fe(III)/H2O2/CAT) systems were compared using atenolol (ATL) as a model contaminant. 91.0% of ATL degradation was reached after 60 min in H2O2 system which was much higher than that in PS system (52.4%) under the same experimental condition. CAT could react directly with H2O2 to produce small amounts of HO• and the degradation efficiency of ATL was proportional to CAT concentration in H2O2 system. However, the optimal CAT concentration was 5 μM in PS system. The performance of H2O2 system was more susceptible to pH than that of PS system. Quenching experiments were conducted indicating that SO4•- and HO• were produced in PS system while HO• and O2•- accounted for ATL degradation in H2O2 system. Seven pathways with nine byproducts and eight pathways with twelve byproducts were put forward in PS and H2O2 systems respectively. Toxicity experiments showed that the inhibition rates of luminescent bacteria were both decreased about 25% after 60 min reaction in two systems. Although the software simulation result showed few intermediate products of both systems were More toxic than ATL, but the amounts of them were 1–2 orders of magnitude lower than ATL. Moreover, the mineralization rates were 16.4% and 19.0% in PS and H2O2 systems respectively.

Guo W., Li P., Du Q., Zhou Y., Xu D., Zhang Z.

The hydrochemical characteristics of phreatic water were evaluated in this study, and the hydrogeochemical processes occurring along groundwater flow paths were analyzed using inverse hydrogeochemical simulations. The spatial distributions of groundwater Fe and Mn contents in the study area, their influencing factors, and their correlative probabilistic human health risks were assessed. The results showed that the order of cation content in phreatic water was Ca2+ > Mg2+ > Na+ > K+ and Ca2+ > Na+ > Mg2+ > K+ in the pluvial-alluvial fan and alluvial plain, respectively. Approximately 92.73% of the phreatic water samples were HCO3-Ca·Mg-type water, and only a few belonged to SO4·Cl-Ca·Mg-type water. Twelve percent and forty percent of the phreatic water in the pluvial-alluvial fan and alluvial plain, respectively, showed Fe and Mn concentrations exceeding China's drinking water standards. Hydrogeochemical simulations using PHREEQC showed some differences in water‒rock interactions between paths and along the same path due to differences in lithological and hydrological conditions. In addition, higher Fe and Mn contents mainly occurred in the Huyi District, as well as in some parts of the alluvial plain aquifer. Moreover, groundwater Fe and Mn contents were mainly influenced by redox potential, infiltration of sewage containing high Fe and Mn concentrations, TDS contents, and groundwater flow rates. In the Wei River basin, the probability of the health risk due to NO3-N, Fe, and Mn was ordered as NO3-N > Mn > Fe. The health risks of NO3-N were 3.1% and 18.3% for adults and children, respectively, and the health risks due to Mn were 2.3% and 4.9% for adults and children, respectively. In contrast, the probability of health risk of Fe was negligible.

Nsabimana A., Li P.

Life and the sustainable growth of socioeconomic sectors such as agriculture and industry depend on groundwater, particularly in arid and semi-arid regions where surface water resources are limited. The objectives of the current study are to characterize groundwater chemistry and assess its suitability for industrial usage in the Guanzhong Basin located in the semi-arid region of northwest China. To better understand the hydrogeochemistry in the study area, statistical analysis, ionic plots and Pearson's correlation analysis were conjunctively used. Finally, a novel industrial water quality index (IndWQI) model was developed in this paper to determine the overall industrial water quality based on scaling, corrosion, and foaming coefficients as well as some physicochemical parameters. The contribution of each parameter to the overall industrial water quality was determined using multivariate statistical analysis approaches. The findings reveal that dissolution of minerals such as calcite, dolomite, anhydrite and gypsum regulate the groundwater geochemistry in the study area. In addition, human activities influence the groundwater quality in the study area. According to the novel IndWQI approach, 78.95 % of the confined water samples and 74.51 % of the phreatic water samples have excellent or good quality, and can be safely used for industrial boilers. The geospatial analysis shows that the most contaminated groundwater samples are mainly located in northeast Xi'an and the northeast region of the Guanzhong Basin. The IndWQI model is trustworthy, as it can combine several water quality indices and give an instantaneous impression of the whole groundwater quality for industrial uses. It can serve as a benchmark for other areas across the world with a comparable climate.

Alam S.M., Li P., Fida M.

Groundwater is a key water source for drinking and irrigation in Bangladesh, and nearly 69% of the total population of Bangladesh lives in rural areas and depends on shallow tube-wells for direct drinking purposes. Literature published from the year 2005 to 2021 along with N-fertilizers data from the fiscal year 1985–1986 to 2021–2022 has been reviewed in this study to understand the current status of groundwater nitrate (NO3−) pollution in rural areas of Bangladesh. The review showed that the farm inputs (N-fertilizers, manure) have the highest contribution (64%) to groundwater NO3− pollution followed by pit latrines (18%) in rural areas of Bangladesh. Based on the urea consumption rate, elevated NO3− concentration in groundwater in some rural areas, and the estimated duration of N-fertilizers accumulation into groundwater, a total of 23 districts are classified as the most vulnerable areas facing severe future NO3− pollution and may cause new concerns to local people's health within the next 3 decades. Most of these districts lie within hydrogeological Zone-I (Tista fan), Zone-II (flood plains), and Zone-III (Pleistocene tracts). After conducting the health risk assessment, this study implies that the safe standard limit of nitrate in drinking water for consumption is below 31 mg/L as NO3− for children. Governments must take immediate and long-term measures to protect public health from groundwater NO3− pollution in rural areas of Bangladesh.

Xu D., Li P., Chen X., Yang S., Zhang P., Guo F.

Wang D., Li P., He X., He S.

Groundwater recharge from precipitation is a complex process that often exhibits strong nonlinearity. This process is influenced by multiple hydrogeological and topographical conditions. This study aims to assess the response of shallow groundwater table to precipitation in the northern piedmont of the Qinling Mountains in China from 2005 to 2015 using a combination of the Mann-Kendall (MK) test, continuous wavelet transform, and cross-wavelet transform. The MK test revealed a slight upward trend of precipitation from 2005 to 2015. In addition, 71% of the shallow groundwater monitoring wells exhibited increasing trends in the groundwater table depth. Continuous wavelet transform demonstrated periodic groundwater responses to precipitation. Both precipitation and groundwater table showed significant monthly oscillation of 9–15 months, while the highest wavelet power was detected at the temporal scale of 12 months. According to the results of the cross wavelet transform, lag times between groundwater level responses and precipitation events were 78, 73, and 99 days for P1-PF1, P2-FT1, and P3-ST1 in pluvial fans, first terraces, and second terraces, respectively. Moreover, the results suggested spatiotemporal variations in the lag time, which might be due to the variation in groundwater levels, aquifer lithology, precipitation intensity, and groundwater exploitation intensity. The current study revealed the spatiotemporal response mechanism of the shallow groundwater to precipitation, providing a scientific basis for assessing the regional water cycle processes and ensuring effective groundwater resource management.

Yang Y., Li P., Elumalai V., Ning J., Xu F., Mu D.

The entropy water quality index (EWQI) is a simple method of comprehensively assessing water quality. This method has been widely used in groundwater quality assessment. However, the number of hydrochemical parameters selected for the evaluation can lead to inconsistent classification criteria. In this study, 12 parameters were selected, based on their importance in the groundwater quality, to redefine the classification criteria of EWQI. Therefore, the modified EWQI approach with updated classification criteria was applied to evaluate groundwater quality in the Zhouzhi Country of the Guanzhong Basin, China. The results show that considering heavy metals in the groundwater quality resulted in different EWQI classification criteria from those previously used in other studies due to the large difference in the national standard limits for heavy metals in different water quality categories. In addition, the improved EWQI showed that 1.41, 63.38, and 35.21% of the groundwater samples in the Zhouzhi County were of excellent, good and moderate groundwater quality, respectively. Compared with other classification criteria, the improved EWQI method considering more water hydrochemical parameters and heavy metal elements is more suitable and reliable for comprehensively evaluating groundwater quality.

Alharbi T., Al-Kahtany K., Nour H.E., Giacobbe S., El-Sorogy A.S.

The contamination and health risks by arsenic and chromium in the Al-Khobar coastal area, Arabian Gulf, have been assessed by examining 29 samples of surface sediment. Several single and complex indices were accounted to assess contamination, while the chronic daily intake (CDI), the hazard index (HI) and the total lifetime cancer risk (LCR) were applied to assess human health. The studied sediments showed absence or low level of As and Cr contamination. Results of CDI suggested a greater intake of As and Cr in children than in adults, mainly by ingestion pathway, reaching >99.5 % from the total for both adults and children. The recorded values of HI indicated not significant non-carcinogenic effects on the human body. LCR was higher in children than in adults. However, the recorded values suggested that the present carcinogenic risk for As and Cr can be considered acceptable or tolerable.

Chen L., Wang J., Beiyuan J., Guo X., Wu H., Fang L.

Soil pollution by potentially toxic trace elements (PTEs) near uranium (U) mines arouses a growing interest worldwide. However, nearly all studies have focused on a single site or only a few sites, which may not fully represent the soil pollution status at the global scale. In this study, data of U, Cd, Cr, Pb, Cu, Zn, As, Mn, and Ni contents in U mine-associated soils were collected and screened from published articles (2006–2021). Assessments of pollution levels, distributions, ecological, and human health risks of the nine PTEs were analysed. The results revealed that the average contents of the U, Cd, Cr, Pb, Cu, Zn, As, Mn, and Ni were 39.88-, 55.33-, 0.88-, 3.81-, 3.12-, 3.07-, 9.26-, 1.83-, and 1.17-fold greater than those in the upper continental crust, respectively. The pollution assessment showed that most of the studied soils were heavily polluted by U and Cd. Among them, the U mine-associated soils in France, Portugal, and Bulgaria exhibited significantly higher pollution levels of U and Cd when compared to other regions. The average potential ecological risk value for all PTEs was 3358.83, which indicated the presence of remarkably high risks. Among the PTEs, Cd and U contributed more to the potential ecological risk than the other elements. The health risk assessment showed that oral ingestion was the main exposure route for soil PTEs; and the hazard index (HI) values for children were higher than those for adult males and females. For adult males and females, all hazard index values for the noncarcinogenic risks were below the safe level of 1.00. For children, none of the HI values exceeded the safe level, with the exception of U (HI = 3.56) and As (HI = 1.83), but Cu presented unacceptable carcinogenic risks. This study provides a comprehensive analysis that demonstrates the urgent necessity for treating PTE pollution in U mine-associated soils worldwide.

Kumar E., Subramani T., Li P., Karunanidhi D.

Guo Y., Li P., He X., Wang L.

Landfilling is the main method used for garbage disposal, but landfill leachate can affect groundwater quality. To study the influence of landfill leachate on groundwater, 6 monitoring wells and 14 domestic wells in and around the Jiangcungou landfill site in northwest China were sampled. Groundwater chemistry characteristics were analyzed, and water quality and health risks were assessed. Saturation index and correlation analysis were used to identify the sources of major ions, and the hydrogeochemical mechanism controlling characteristic contaminants was analyzed. The result of single-factor water quality evaluation showed that 35% of groundwater samples had at least one indicator exceeding the drinking water standards. It was confirmed that the landfill had an impact on groundwater, as the average pollution index of the monitoring wells (0.72) was significantly higher than that of the domestic wells (0.31). The major characteristic pollutants were iron (Fe), manganese (Mn), arsenic (As) and fluoride (F−), and their average pollution indices were 12.91, 1.78, 1.1, and 2.47, respectively. The average non-carcinogenic health risks of F−, NO3− and As were 0.96, 0.58, and 0.42, respectively, while the average carcinogenic risk for arsenic was 1.90E−04. The landfill is in the methane production stage, resulting in a reducing redox environment. Among the four characteristic pollutants, Fe and Mn resulted mainly from the landfill, while As and F− were affected by the landfill as well as slow groundwater flow and other human activities. Necessary measures were also proposed to prevent groundwater pollution in and around the landfill.

Archer E., Volschenk M., Brocker L., Wolfaardt G.M.

This study evaluated the occurrence and fate of fourteen contaminants of emerging concern (CECs) at two South African wastewater treatment works (WWTW). Daily loads of the drug targets were calculated in the aqueous phase of influent- and effluent wastewater to evaluate their fate at the treatment works, along with population-normalised daily loads in raw influent wastewater to identify community-wide substance use patterns in the two study areas. Environmental risk characterisation of the CECs at WWTW effluent discharge was done using conventional risk quotient (RQ) estimations. A significant reduction of most CECs was observed at both WWTW locations, except for some that have been previously recorded to persist through various WWTW processes globally, including the illicit drug methaqualone that was reported here for the first time to evaluate its fate during wastewater treatment, substance use trends, and potential toxicological risk. Moderate-to high-RQs were estimated for several target CECs during the sampling period for both treatment facilities. The results presented here suggest the need for a multi-disciplinary approach to WWTW monitoring of CECs and highlight the need for further refinement of risk assessment approaches to mitigate recalcitrant- or pseudo-persistent CECs in wastewater discharge. Such refinement should include: (1) identifying the potential ecological risk on a wider range of sentinel indicators, (2) interaction of CECs with various biochemical pathways (including sub-lethal toxicity responses), (3) identifying the persistence and toxicological risks of breakdown products and (4) partitioning of CECs in the aqueous environment and/or bioaccumulation in freshwater biota.

Saghafi M., Shariatifar N., Alizadeh Sani M., Dogaheh M.A., Khaniki G.J., Arabameri M.

In this study, the trace elements lead (Pb), arsenic (As), cadmium (Cd), nickel (Ni), copper (Cu), zinc (Zn) and iron (Fe) quantity have been investigated using graphite furnace atomic absorption s...

Liu L., Wu J., He S., Wang L.

In this paper, the spatial distribution of fluoride (F‒) and manganese (Mn) in groundwater was described and the overall groundwater quality was assessed with the entropy weight water quality index (EWQI) in Weining Plain, northwest China. The probabilistic health risk of F‒ and Mn in groundwater was assessed by the Monte Carlo stochastic simulation method. The results show that 50 groundwater samples (a total of 144) belong to poor and very poor quality because of agricultural activities, industrial development, and the local hydrogeological conditions. Groundwater quality in the upper reaches of the Yellow River is better than that in the lower reaches. The average health risks faced by children and adults are 4.59 and 0.62, respectively. If the uncertainty of the model parameters are considered, the mean risks faced by children and adults are 6.84 and 0.92, respectively, indicating that the health risk to residents, especially children, cannot be ignored. Compared with dermal contact, drinking water intake is the main exposure way to harm residents’ health. F‒ contributed higher to the health risk than Mn, and children face greater risk than adults. Stochastic simulation can reflect health risks more comprehensively than the deterministic methods. The study results are helpful for decision makers to take measures for the safe supply of drinking water in the study area.

D. K., P. A., T. S., Setia R.

• Groundwater of the study region is high to very high saline and low alkaline in nature. • Around 53% of the total area has good quality groundwater for drinking water supply. • Southeast part has poor groundwater quality due to less recharge from surface water bodies. • Nearly 82% of the groundwater samples possess health risks for infants in the study region. The main objective of the present investigation is to estimate groundwater suitability for sustainable drinking water supply and food production in a semi-urban area of south India with a focus on risk assessment for making healthy society. As urbanization and industrialization make the water unfit for water supply and crop rising in most parts of the world this study is very much significant for the fast growing Edappadi region in the southern part of India. A total of sixty-nine groundwater samples were obtained during May 2019 (summer season) and analyzed for Total Dissolved Solids (TDS), Electrical Conductivity (EC), pH, potassium (K + ), magnesium (Mg 2+ ), sodium (Na + ), calcium (Ca 2+ ), bicarbonate (HCO 3 − ), nitrate (NO 3 − ), sulphate (SO 4 2- ), chloride (Cl − ), and fluoride (F − ). Fluoride and nitrate ranged from 0.38 to 3.23 mg/L and 12 to 136 mg/L with an average of 1.7 mg/L and 62 mg/L, respectively. About 36 % of samples occupying 80.74 km 2 area surpass the allowable limit of fluoride (1.5 mg/L). Similarly, 42 % of samples occupying 98.75 km 2 area surpass the allowable limit of nitrate as per WHO and BIS standards (45 mg/L). Correlation studies point out that groundwater contamination is happening due to manmade activities. The Improved Water Quality Index (IWQI) suggested that about 57% of groundwater samples can be used for drinking utility. The alkalinity of groundwater is within the suitable level for crops but groundwater salinity is high to very high in most of the areas. The Total Hazard Index (THI) showed that 72%, 59%, 33% and 29% and 86%, 77%, 51% and 43% of groundwater samples are within the non-carcinogenic health risk category based on fluoride and nitrate contents, respectively, for infants, children, teens, and adults. This study will help the decision and policymakers such as municipal corporation, pollution control board, public works department, water supply and drainage boards, agricultural and public health departments, etc., to use appropriate groundwater resources for providing safe drinking water supply and food production from crops. The findings of this study can aid in the development of appropriate management strategies by the above government departments for ensuring safe water supply and health protection measures for inhabitants.

Preethi B., Subramani T., Saravanan, Gopinathan P., Huang Z., Kumar B.

Mahmoodi N.M., Ghadirli M.M., Hayati B., Mahmoodi B., Rabeie B.

Musielak M., Serda M., Malecka M., Gągor A., Dreszer D., Szubka M., Sitko R.

Adnan M.A., Majnis M.F., Adnan W.N., Abdullah N.H., Baharom A.S., Julkapli N.M.

Macrì A., Agostino E., Spagnuolo D., Trombetta D., Smeriglio A., Spanò A., Morabito M., Genovese G., Caccamo M.T., Magazù S., Nicolò M.S., Zammuto V., Gugliandolo C.

Sukarjo, Dewi Yustika R., Oktasari Handayani C., Dewi T., Yustiawati, Yanti D., Dariah A.

Bhattacharya S., Kolandhasamy P., Mandal A., Rajaram R., Darbha G.K.

Ajab H., Khan M.H., Naveed P., Abdullah M.A.

Sivaraman S.P., Srinivasan P., Madhu D.K., Deivasigamani P., Mohan A.M.

Buzukashvili S., Sommerville R., Kökkılıç O., Ouzilleau P., Rowson N.A., Waters K.E.

Milijašević Joksimović D., Jakovljević D., Jojić Glavonjić T.

This study evaluates the water quality of the Tamiš River, a tributary of the Danube, at the Jaša Tomić and Pančevo hydrological stations from 2011 to 2016 and from 2018 to 2022, using the Water Pollution Index (WPI) and seasonal analysis. The analysis revealed elevated nitrite and orthophosphate concentrations at both stations, with Pančevo exhibiting extreme microbial contamination in 2015, attributed to urban runoff, agricultural activities, and inadequate wastewater treatment. Seasonal results indicate that while spring conditions align with Class I water standards, summer presents critical risks, especially at Pančevo, where the highest WPI value (26.47 in 2015) was recorded. Autumn shows stabilization, though sporadic WPI peaks reflect the impact of nutrient runoff. Winter conditions are marked by stability, with favorable dissolved oxygen levels but occasional exceedances in heavy metals, particularly at Jaša Tomić. Increased concentrations of suspended solids and heavy metals at Jaša Tomić emphasize diverse pollution sources, including industrial discharges and soil erosion. These findings underscore the necessity of integrated water management strategies, such as wastewater treatment upgrades and sustainable agricultural practices, to mitigate pollution. Protecting the Tamiš River is crucial for supporting biodiversity, safeguarding public health, and ensuring sustainable use of this vital Danube tributary.

Yang R., Sha Y., Sun Z., Yang B., Solangi F.

Substantial amounts of nitrogenous (N) compounds, as well as bisphenol A (BPA) and bisphenol S (BPS), contribute to the impurities of pharmaceutical contamination (PC) in wastewater, which have detrimental effects on the environment, humans, and aquaculture. The anammox processes is primarily used to treat wastewater contamination, in which certain microbial communities play a crucial role. In this regard, the present study focuses on microbial communities and the functional genes involved in the anammox process. Further, the current study highlights the secondary (biological) and tertiary (advanced) methods; these techniques are more effective solutions for PC treatment. Anammox bacteria are the primary drivers of the wastewater’s ammonium and nitrite removal process. However, overall, 25 anammox species have been recognized between five important genera, including Anammoxoglobus, Anammoximicrobium, Brocadia, Kuenenia, and Jettenia, which are mainly found in activated sludge and marine environments. The group of bacteria called anammox has genes that encode enzymes such as hydrazine synthase (HZS), hydrazine dehydrogenase (HDH), nitrite oxidoreductase reductase (NIR), hydroxylamine oxidoreductase (HAO), and ammonium monooxygenase (AMO). The anammox process is responsible for developing about 30% to 70% N gases worldwide, making it a critical component of the nitrogen cycle as well. Therefore, this review paper also investigates the pathways of hydrazine, an intermediate in the anammox process, and discusses the potential way to significantly decrease the N-compound contamination from wastewater systems and the environmental effects of determined organic contaminants of BPA and BPS.

Mustafa G., Noreen S., Ahmad A., Iqbal D.N., Rizwan M., Jilani M.I., Ahmad M., Munir S., Kennedy J.F.

Li C., He S., Mo H., Xu X., Yang P., Liu M.

Fe2O3-based photocatalysis is one of the most promising technologies for the removal of pollutants in water.

Arif M., Tahir F., Hussain T., Alrokayan S., Akhter T.

Aromatic compounds containing aldehyde and nitro groups are very toxic to human health. Moreover, complete degradation of these compounds is not possible.