Health risk assessments of arsenic and toxic heavy metal exposure in drinking water in northeast Iran

Meta-analysis of TLR4 pathway-related protein alterations induced by arsenic exposure

Arsenic is a toxic metal, which ultimately leads to cell apoptosis. TLR4 signaling pathway played a key role in immunomodulatory. Therefore, alterations in related proteins on the TLR4 signaling pathway induced by arsenic exposure was systematically reviewed and analyzed by meta-analysis. Some databases were searched including PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and WANFANG MED ONLINE. The results of NF-κB, IKK, NF-κBp65, phospho-NF-κBp65, and TLR4 expressions were analyzed by Review Manage 5.3. In the arsenic intervention group, NF-κB, phospho-NF-κBp65, and TLR4 expression levels were higher than the control group, respectively. SMD and 95%CI were 11.29 (6.34, 16.24), 4.71(1.73, 7.68), and 5.79 (-4.22, 15.80). Compared to controls, in the exposed group, IKK levels were found to be 38.11-fold higher (Z = 0.97; P = 0.33); NF-κBp65 levels were found to be 0.92-fold higher (Z = 3.33; P = 0.0009) for normal cells and tissue, while IKK levels were found to be 5.18-fold lower (Z = 5.34; P < 0.0001); NF-κBp65 levels were found to be 2.01-fold lower (Z = 3.87; P = 0.0001) for abnormal cells. With comparing of low dose, high dose of arsenic exposure was found to reduce the expression of NF-κB, but increase the expression of NF-κBp65. This review supports the alterations in related proteins on the TLR4 signaling pathway induced by arsenic exposure, which is helpful to provide theoretical basis for the mechanism of toxicity of arsenic-induced immune system damage.

Water quality and health risk assessment of trace elements in surface water at Punjnad Headworks, Punjab, Pakistan

Pollution of the aquatic ecosystem due to different trace elements has become a global concern which has raised health-related issues for both aquatic and human life. Industrial and agricultural water run-off drained into the rivers and deposit trace elements in water, sediments and planktons. This study was designed to calculate the burden of trace elements such as aluminium (Al), arsenic (As), barium (Ba), and lead (Pb) in the river water of Punjnad Headworks, Bahawalpur, Punjab, Pakistan. Samples were collected from surface water, bed sediments and planktons during autumn, winter and spring seasons (September 2018 to May 2019). The results showed that the concentration of Pb was highest in surface water (453.87 mg L^-1), while that of Al was highest in sediments (370.24 µg g^-1) and plankton (315.05 µg g^-1). A significant difference was found in metal concentrations among surface water, bed sediments and plankton at different sampling stations during various seasons. Importantly, the Exp_ing (0.71, 1.23^-3, 0.34, 0.02 for Pb, As, Al, and Ba, respectively) and Exp_derm (7.09^-8, 1.23¹⁰, 3.42^-8, and 2.48^-9 for Pb, As, Al, and Ba, respectively) for trace elements were below 1.0 suggesting non-significant adverse effects of trace elements on human health. This study provided better understanding of various pollutants and their concentrations in water sources at the studied location.

Health risk assessment of groundwater nitrogen pollution in Yinchuan plain

High nitrogen concentration of groundwater poses a threat to human health. This study evaluated the potential health risk of nitrogen pollution in Yinchuan plain by geostatistical analysis and triangular stochastic model considering different land use types, and identified the uncertainties of the parameters. 163 samples were collected from groundwater wells in different land use types. The results show that the concentration of NO₃^--N ranges from 0.059 to 450 mg/L, with an average of 22.439 mg/L. Approximately 32% of the samples exceed Grade III threshold (20 mg/L of N). The concentration of NH₄⁺-N ranges from 0.011 to 11 mg/L, with an average of 0.456 mg/L. The concentration of NO₂^--N ranges from 0.003 to 9.09 mg/L The NO₃^--N and NH₄⁺-N concentration in the groundwater of the unutilized land use is significantly lowest among all the land types. The concentration of nitrogen is highest in farmland use. The ranking of non-carcinogenic risk under different land types for infants, children, adult males and females is: farmland use > residential land use> unutilized land use. The non-carcinogenic risk value of farmland use is three times as much as that of the residential land use. Drinking groundwater can be potentially harmful to human health, and nitrogen pollutants pose an even greater threat to infant. At the same time, considering the impact of different land use types on groundwater would avoid overestimating or underestimating regional risk value. Triangular stochastic model is more sensitive to data changes and can reduce uncertainty. The contribution rate of nitrate concentration to risk is more than 83%, indicating that random sampling is needed to improve the reliability of evaluation results. The research results of this study will provide a new way to solve the uncertainty in groundwater security management.

Assessment of physical and chemical properties, health risk of trace metals and quality indices of surface waters of the rivers and lakes of the Kola Peninsula (Murmansk Region, North-West Russia)

The pollution of waterbodies with trace metals is of concern throughout the world due to their high toxicity. One of the main anthropogenic sources of trace metals entering natural waters is the mining and processing of minerals. Intensive development of the mining industry on the Kola Peninsula (the Murmansk region, Russia), exploration and development of new mineral resources have led to a sharp deterioration in the quality of surface waters of rivers and lakes. As a result of anthropogenic impact, accumulation of a wide range of metals (mainly Cu, Ni, Co, Pb, Cd, Mn, Sr, Al and Fe) is observed, as well as significant changes in the physicochemical parameters and radioactive conditions of surface waters. The most polluted waterbodies of the Kola Peninsula are located in the Monchegorsk, Olenegorsk and Apatit regions. Consumption of water from investigated contaminated sources can cause various high risks of human health. The results of this study will provide an informative basis for future risk assessments of the environment and human health, as well as for the development of integrated measures for managing the quality of surface waters of lakes and rivers of the Kola Peninsula.

Evaluation of occurrence of organic, inorganic, and microbial contaminants in bottled drinking water and comparison with international guidelines: a worldwide review

The aim of this study was to evaluate the levels of inorganic and organic substances as well as microbial contaminants in bottled drinking water on a global scale. The findings were compared to WHO guidelines, EPA standards, European Union (EU) directive, and standards drafted by International Bottled Water Association (IBWA). Our review showed that 46% of studies focused on the organic contaminants, 25% on physicochemical parameters, 12% on trace elements, 7% on the microbial quality, and 10% on microplastics (MPs) and radionuclides elements. Overall, from the 54 studies focusing on organic contaminants (OCs) compounds, 11% of studies had higher OCs concentrations than the standard permissible limit. According to the obtained results from this review, several OCs, inorganic contaminants (IOCs), including CHCl3, CHBrCl2, DEHP, benzene, styrene, Ba, As, Hg, pb, Ag, F, NO3, and SO4 in bottled drinking water of some countries were higher than the international guidelines values that may cause risks for human health in a long period of time. Furthermore, some problematic contaminants with known or unknown health effects such as EDCs, DBP, AA, MPs, and some radionuclides (40K and 222Rn) lack maximum permissible values in bottled drinking water as stipulated by international guidelines. The risk index (HI) for OCs and IOCs (CHBrCl2, Ba, As, and Hg) was higher than 1 in adults and children, and the value of HI for CHCl3 in children was more than 1. Thus, further studies are required to have a better understanding of all contaminants levels in bottled drinking water.

Tap Water Consumption Is Associated with Schoolchildren’s Cognitive Deficits in Afghanistan

Environmental influence on intelligence quotient (IQ) is poorly understood in developing countries. We conducted the first cross-sectional investigation to assess the role of socio-economic and environmental factors on schoolchildren’s IQ in Jalalabad, Afghanistan. A representative sample of 245 schoolchildren aged 7–15 was randomly selected in five schools. Children’s records included: non-verbal IQ TONI-1 scale, body mass index, socio-economic status, and further environmental indicators (water supply, proximity to a heavy-traffic road, use of surma traditional cosmetics). The mean age of the children was 11.7 years old (±2.0 years), and 70.2% and 29.8% were male and female, respectively. The children’s mean IQ was 83.8 (±12.6). In total, 37 (14.9%) of the children were overweight, 78 (31.5%) were living below the USD 1.25 poverty line, 133 (53.6%) used tap water supply, 76 (30.6%) used surma, and 166 (66.9%) were exposed to heavy road traffic. The children’s IQ was significantly and independently lowered by tap water use (−3.9; 95% CI [−7.1; −0.6]) and by aging (−1.4; 95% CI [−2.2; −0.6]), as revealed in multivariate analysis, independently of gender, socio-economic status, exposure to heavy road traffic, overweight status, and surma use. Lower IQ among older children is possibly attributed to chronic stress experienced by adolescents due to living conditions in Afghanistan. While using tap water prevents fecal peril, it may expose children to toxic elements such as lead which is known to lower their intellectual development.

A comparative study, distribution, predicted no-effect concentration (PNEC) and contamination assessment of phenol with heavy metal contents in two coastal areas on the Egyptian Mediterranean Sea coast

This study comparing the expected pollution status of phenol along with heavy metals in sediments of two economic regions on the Mediterranean Sea coast using equilibrium partitioning method (EPM) as well as exposure of fishermen and populations to these sediments through ingestion and skin contact while swimming. El-Dekhila (ED) and Abu Talat (AT) regions were different in sediment texture and pollution sources. The expected ecological hazards of phenol in the studied areas were carried out using the equilibrium partitioning method (EPM) by which the partition coefficient of organic carbon-water, K_OC (logK_OC> 0.95-3.49), octanol-water coefficient, K_OW (logK_OW> 1.46-1.48) and sediment/liquid partition coefficient, K_d (log K_d < 3) detected high availability amounts of phenol in seawater. Risk quotient (RQ) for phenol in ED region ranged from high to moderate risk, while for AT region was low risk (<0.1); whereas, RQ values of heavy metals in sediments of two studied areas reflected the overall low risk without human hazards (HQ & HI < 1). RQ_Acute and RQ_Chronic values were above 1 for phenol and heavy metals (Cu and Zn) reflecting that fish were the most sensitive to them in the two regions. Interestingly, this current investigation predicts future contamination of the studied areas especially phenol contamination and its relationship to heavy metals using some reasonable information and allowing the managers to manage how they decide on and protect these two areas. Thus, there is a constant need to use relatively simple tools capable of ensuring protection objectives with a quantity of information with realistic feasibility.

Health Risks for a Rural Community in Bokkos, Plateau State, Nigeria, Exposed to Potentially Toxic Elements from an Abandoned Tin Mine

The past mining activities in Bokkos Local Government Area (LGA) were performed in an uncontrolled way and gave rise to many abandoned ponds now serving as domestic and irrigation water sources. Past research focused mainly on the environmental impact, and we show for the first time what the human health risk through consumption of contaminated food crops is in these communities. This study was designed to determine the level of Potentially Toxic Elements (PTEs) contamination in pond water, soil, and food crops and assess the health risk of inhabitants in the abandoned tin mining community in Bokkos LGA. Samples of the mining pond water, soil, and selected food crops from farms irrigated with the pond water: bitter leaf (Vernonia amygdalina), pepper (Piper nigrum), okra (Albelmoschus esculentus), maize (Zea mays), sweet potato (Ipomoea batatas), and Irish potato (Solanum tuberosum) were analyzed for each of the eight PTEs (viz. Cu, Cr, Fe, Mn, Ni, Zn, Cd, and Pb) using inductively coupled plasma optical emission spectrometry (ICP-OES). The results obtained showed that the levels of all the PTEs analyzed in the soil, pond water, and selected food crops except for Fe and Mn in soil and Cd in sweet potato were greater than their corresponding background area values (p < 0.05). Also, the mean concentrations of all the PTEs except for Cu in pond water were significantly (p < 0.05) higher than the WHO maximum permissible limit. With the exception of Fe, Ni, and Zn for pepper and okra, Cu and Fe for maize grains as well as Cu, Ni, and Zn for sweet and Irish potatoes and Fe and Cd for sweet potato, the mean concentrations of PTEs in the food crops were significantly higher than WHO maximum permissible limit. The EF values of Cd (0.39); Cu (3.59) and Ni (2.81); Cr (9.38) and Pb (17.84); and Mn (178.13) and Zn (83.22) classified the soil as minimally, moderately, significantly, and extremely highly enriched, respectively. The PI values of all the PTEs in the soil studied were all greater than 5, indicating that the soils were severely contaminated. There was evidence that food crops significantly bioaccumulated PTEs either as a result of contaminated soil and/or irrigation water. The bioaccumulation was not uniform and was dominated by transfer from the polluted irrigation water. The bitter leaf, okra, and to some extent maize had the highest transfer of PTEs, and Mn, Cu, and Zn had the highest bioaccumulation in the food crops investigated. The hazardous index (HI) for the eight PTEs through the consumption of food crops was 107 for children and 33 for adults which greatly exceeded the recommended limit of 1, thus indicating that possible health risks exist for both local children and adults. For every PTE, the values of HI for children are many-fold higher than those for adults, which is of particular concern due to the high HI values for Pb found for maize consumption, a typical staple food. The cancer risk values for Cr and Ni for all the food crops were within 10^-3-10^-1 which is several fold higher than the permissible limits (10^-6 and < 10^-4) indicating the high carcinogenic risk. It can be concluded based on the results and risk assessment provided by this study that human exposure to mining pond water and soil in farms around the mining pond through the food chain suggests the high vulnerability of the local community to PTE toxicity. Long-term preventive measures to safeguard the health of the residents need to be put in place.

In Situ Measurements of Domestic Water Quality and Health Risks by Elevated Concentration of Heavy Metals and Metalloids Using Monte Carlo and MLGI Methods

The domestic water (DW) quality of an island province in the Philippines that experienced two major mining disasters in the 1990s was assessed and evaluated in 2021 utilizing the heavy metals pollution index (MPI), Nemerow’s pollution index (NPI), and the total carcinogenic risk (TCR) index. The island province sources its DW supply from groundwater (GW), surface water (SW), tap water (TP), and water refilling stations (WRS). This DW supply is used for drinking and cooking by the population. In situ analyses were carried out using an Olympus Vanta X-ray fluorescence spectrometer (XRF) and Accusensing Metals Analysis System (MAS) G1 and the target heavy metals and metalloids (HMM) were arsenic (As), barium (Ba), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn). The carcinogenic risk was evaluated using the Monte Carlo (MC) method while a machine learning geostatistical interpolation (MLGI) technique was employed to create spatial maps of the metal concentrations and health risk indices. The MPI values calculated at all sampling locations for all water samples indicated a high pollution. Additionally, the NPI values computed at all sampling locations for all DW samples were categorized as “highly polluted”. The results showed that the health quotient indices (HQI) for As and Pb were significantly greater than 1 in all water sources, indicating a probable significant health risk (HR) to the population of the island province. Additionally, As exhibited the highest carcinogenic risk (CR), which was observed in TW samples. This accounted for 89.7% of the total CR observed in TW. Furthermore, all sampling locations exceeded the recommended maximum threshold level of 1.0 × 10⁻⁴ by the USEPA. Spatial distribution maps of the contaminant concentrations and health risks provide valuable information to households and guide local government units as well as regional and national agencies in developing strategic interventions to improve DW quality in the island province.

Interactive toxicity of copper and cadmium in regenerating and adult planarians

In a polluted environment, metals are present as complex mixtures. As a result, organisms are exposed to different metals at the same time, which affects both metal-specific as well as overall toxicity. Detailed information about the molecular mechanisms underlying the adverse effects of combined exposures remains limited in terms of different life stages. In this study, the freshwater planarian Schmidtea mediterranea was used to investigate developmental and physiological responses associated with a combined exposure to Cu and Cd. In addition, the cellular and molecular mechanisms underlying the provoked adverse effects were studied in different exposure scenarios. Mixed exposure resulted in a decline in survival, diverse non-lethal morphological changes, neuroregenerative impairments, altered behaviour and a limited repair capacity. Underlying to these effects, the cellular redox state was altered in all exposure conditions. In adult animals, this led to DNA damage and corresponding transcriptional changes in cell cycle and DNA repair genes. In regenerating animals, changes in hydrogen peroxide and glutathione contents led to regenerative defects. Overall, our results demonstrate that (1) developing organisms are more susceptible to metal exposures, and (2) the toxicity of an individual metal increases significantly in a mixed exposure scenario. These aspects have to be included in current risk assessment strategies.

Occurrence of Potentially Toxic Elements in Bottled Drinking Water-Carcinogenic and Non-Carcinogenic Risks Assessment in Adults via Ingestion

The presence of potentially toxic elements in drinking water can be dangerous for human health because of their bioaccumulation and toxicity, which is a huge concern for many researchers. In the case of bottled water, the exposure to toxic elements is achieved, especially by ingestion, leading to disorders of important functions of the human body. The aim of this study was the detection of some potentially toxic elements, from 50 samples of bottled drinking water, available on the Romanian market. Based on obtained concentrations, an assessment of the carcinogenic and non-carcinogenic health risk was performed. The concentrations of potentially toxic elements analyzed were below the maximum allowable limits, for all contaminants, excluding Pb and Fe. Moreover, the results of total risk via ingestion, showed that 30% of samples had an Hazard Quotient (HQ) < 1, and 70% had an HQ > 1; which implies a potential risk following the consumption of those samples. Concerning total cancer risk, 28% of the samples are in the acceptable level, while 72% of the samples are considered harmful and can lead to a type of cancer after repeated exposure. The study concluded that long term use of bottled water of poor quality may pose a hazard to human health; it is helpful for inhabitants to avoid ingestion of contaminated water.

The Content and Toxicological Risk Assessment of Trace Elemental Impurities (Pb and Cr) in Snacks from Ogun State, Southwestern Nigeria

The monitoring of food contamination by trace elemental impurities (TEIs) are major health challenges in developing countries. The present study evaluated the content and toxicological risk assessment of TEIs in commonly consumed snack/junk foods from Ogun State, Nigeria. TEIs (Pb and Cr) were determined in sixty snack food samples purchased from Ijebu Ode, Ogun State, southwestern Nigeria. The TEIs were analysed in quadruplicates using atomic absorption spectrometry with flame atomization. TEI data were subjected to simple descriptive and inferential statistics. The toxicological risk assessment of TEIs was evaluated for hazard quotient (HQ), hazard index (HI) and cancer risk (CR) using the United States Environmental Protection Agency-Integrated Risk Information System (USEPA-IRIS) model. Data showed the varying Pb levels of 8.22 ± 1.57 mg/kg in sausage to 12.25 ± 4.27 mg/kg in cocoyam chips higher than the permissible limit of the Codex Alimentarius of the Joint World Health Organization and Food and Agriculture Organization. The toxicological risk assessment revealed the HQs greater than 1.0 for Pb and Cr in most snack foods consumed by adults and children, indicating adverse health problems. The CRs of Pb (children) and Cr (adults and children) also breached the acceptable limit of 1.0 × 10^-4, signifying possible lifetime development of cancer. It is therefore necessary to periodically monitor the TEIs in snacks to protect the public health.

Socio-Environmental Determinants and Human Health Exposures in Arid and Semi-Arid Zones of Iran-Narrative Review

Lifestyle is different in arid and semi-arid zones. However, where people are born and live have a lasting influence on their social and environmental exposure. This review focuses on the, various dimensions of environmental health imbalance inequality especially in significant environmental sources such as (ie, air, water, soil) among provinces that creates a big health gap in the center, East and the Southeast of Iran. Thus, the population of the arid and semi-arid zones of Iran is facing respiratory, cardiovascular, cancer and infection diseases linked to environmental problems such as chemical and microbial pollution due to air pollution and unsafe water sources, respectively. The prevalence of certain types of cancer such as skin, stomach, bladder, prostate and colorectal cancer together with some respiratory and cardiovascular diseases in arid and semiarid zones such as Kerman, Yazd, etc., has been reported in comparison with other provinces frequently. These impacts have effects on multiple levels of health security in those zones. Based on these concerns, we propose key questions that should guide research in the context of the socio environmental science to support science-based management actions in Iran and other similar semi-arid areas worldwide.

Evaluating the consequences of household hazardous waste diversion on public health and ecological risks of leachate exposure

Household hazardous waste (HHW) includes approximately 1% of municipal solid waste (MSW), which is related to the lack of efficient separate collection schemes co-disposed with MSW in many countries worldwide. In this research, the effect of HHW diversion on leachate quality and consequent reduction in risks to the environment and human health was investigated. In this regard, physicochemical parameters of MSW leachate samples with and without hazardous fraction were characterized. Next, leachate pollution index (LPI) and associated risks were assessed. The results showed that the source separation of HHW decreases the LPI value by 13.48% and improves the potential of leachate for biological treatment, leading to a reduction in leachate treatment costs and complexity. Based on risk assessment results, HHW diversion could lower cancer risks of organic compounds and heavy metals to acceptable levels for adults and children. Moreover, by the source-separating of HHW, hazard indices for aquatic and terrestrial bioassays reduced by 41.5 and 36%, respectively. Furthermore, despite the comparatively low generated amount of HHW, this fraction should be emphasized due to its unintended effects for public health and the environment.

An Insight into Pathway and Health Risk Assessment of Toxic Metals in Herbal Medicine

Introduction. Along with and in competition with orthodox medicines, herbal medicines have converted into a popular form of cure. While cumulative investigation reports on adverse effects by herbal drug uptake are few, systematic review along with deep insight into other relevant topics (carcinogenic and noncarcinogenic risk assessment, mechanism of toxicity, and entering toxic metal from source to herbal drug) is sporadic. Methods. Therefore, existing research and their published outputs pointing safety assessment of herbal medicines in terms of toxic metals have been reviewed systematically and information synthesized thematically while suggesting mechanism of toxicity, consequence of prolong exposure, and pathway of toxic metal from source to herbal drugs. Result and Discussion. Our study suggests that most of the herbal medicines were unsafe to consume although claimed harmless. Possible pathways regarding migration of toxic metals into herbal medicine are discussed. Conclusion. There should have appropriate screening from herb collection, and manufacturing to selling of finished herbal medicine by authority concerned is backed.

A Survey on Nanotechnology-Based Bioremediation of Wastewater

Rainwater discharge and human impacts produce wastewater, which is a contaminated type of water. Sediments also discharge phosphate into the water column when there is a lack of dissolved oxygen in the water. Through the manufacturing of environmentally benign nanoparticles, nanotechnology may reduce the amount of money spent by enterprises to remediate such contaminants. Because of their improved physiological, biochemical, and biomechanical qualities, nanoparticles are getting prominence. The importance of the global wastewater dilemma is discussed in this survey. The use of nanomaterials in heavy metal remediation (HMR) and wastewater treatment is covered in this survey. This paper also discusses the benefits of nanotechnology over traditional approaches in certain fields. This survey aims to gather together many recent studies on nanoparticle production and their benefits as adsorbents in the remediation of wastewater which have been done so far. The promising role of nanotechnology in wastewater remediation is surveyed in this research, which also discusses recent developments in nanotechnology-mediated remediation methods. This survey examines the vital potential of nanotechnology in wastewater treatment, as well as recent breakthroughs in nanotechnology-mediated treatment systems.

Non-carcinogenic risk assessment of exposure to heavy metals in underground water resources in Saraven, Iran: Spatial distribution, monte-carlo simulation, sensitive analysis

Groundwater aquifers are considered the second most abundant water supply for drinking water all over the world. In Iran, ground waters are commonly employed for drinking water, irrigation, and industrial purposes. Heavy metals (HMs) pose human concerns about the groundwater contamination; these pollutants are recognized to be capable of bio-accumulation, long persistence in the natural environment, and toxic effects. In the present research, the content of HMs: Chromium (Cr), Cadmium (Cd), and Lead (Pb) were detected in 89 water samples collected in 2018 by underground water supplies (active wells) of Saravan city. Hazard Quotient (HQ) and Monte Carlo Simulation approach with 10,000 repetitions were applied to discover the human non-carcinogenic impacts of HMs in four groups of ages (adults, teenagers, children, and infants) of consumers. The concentrations of Cr, Pb, and Cd were in the range of 0.49-20, 0.1 to 58.34, and 0.11-12.8 μg/L, respectively. The mean HQ calculated due to exposure to Pb (0.0018-0.0023), Cr (0.0112-0.0186), and Cd (0.0370-0.0615) were lower than one. The findings of sensitivity analysis revealed that HMs concentration had the most contribution effect on human non-carcinogenic risk analysis in four different exposed populations. This study could assist researchers to perform more comprehensive studies with more samples. Therefore, further research is required for decision-makers to plan proper measurements properly.

Surface water quality analysis using multivariate statistical techniques: a case study of Fars Province rivers, Iran

This study aimed to transform the input of a large dataset into the output of interpretable information. Hence, multivariate statistical methods were carried out to analyze physicochemical parameters in 34 rivers during a 17-year period (1997-2014). Cluster analysis divided the study area into spatially different riverine water quality sub-regions described in ascending order of water quality as severely polluted (SP), highly polluted (HP), polluted (P), moderately polluted (MP), lightly polluted (LP), and not polluted (NP). By diagnosing threats and identifying fragile zones, water contamination sources responsible for impaired water quality in the study area recognized as natural pollutants in LP, municipal wastes in P, discharge of industrial effluents in MP, natural geochemical formations in SP and HP, and superficial flows of agricultural lands in SP, HP, and MP. The dominant water type in each zone was classified into Na-Cl, Na-Cl, Na-Mg-Ca-Cl-SO₄, Na-Ca-Mg-Cl-SO₄, Na-Ca-Cl, and Ca-Mg-HCO₃-SO₄ groups for SP, HP, P, MP, LP, and NP, respectively. To explore aesthetic aspects of drinking water application, hazard quotient (HQ) was applied for children and adults in terms of ingestion and dermal exposure. Overall health risk assessment revealed the order of impacts of the secondary water quality parameters as Cl^-  > Na⁺  > total dissolved solids (TDS) > Ca²⁺  > SO₄^2-  > Mg²⁺. Furthermore, hazard index (HI) ranged from 0.011 to 31.439 and 0.010 to 30.122 for children and adults, respectively, indicating a potential health risk regarding chloride throughout the whole region excluding NP. To identify significant agents in water quality, principal component analysis extracted 3 varifactors (VFs), with the eigenvalues of 4.74, 1.19, and 0.85, respectively, explained about 83% of the variance. The most important parameters in the first factor were TDS, electrical conductivity, SAR, TH, Na⁺, Cl^-, and SO₄^2- accounting for 58% of the total variance. The most influenced parameters in the second and third factors were pH and HCO₃^-, respectively, with variance coverage of 26%. These factors indicated that the hydrochemical characteristics of the water originated by natural interactions (existing salt domes, evaporation, weathering, and soil erosion) and anthropogenic activities (fertilizer-rich flows of agro-fields and domestic/industrial disposals), which must be minimized in rivers to supply the population with hygienic water.

Assessment of Potentially Toxic Elements and Associated Health Risk in Bottled Drinking Water for Babies

Potentially toxic elements are chemical pollutants which are dangerous to human health, especially for babies and children. Because their presence has been detected in baby food and baby drinking water, exposure to these elements is mainly due to ingestion. For this reason, the main objective of this study was quantification of 12 potentially toxic elements, including Ba, Co, Cu, Zn, Mn, Ni, Li, Fe, Pb, Cd, Cr, Sb, by ICP–MS, from 19 samples of bottled baby water. Based on the levels obtained, a health risk assessment was performed of the risk caused by their consumption, as well as an analysis of the quality of the samples. Excep iron, the values obtained for all other metals were below the limits imposed by the legislation in force. The risk analysis shows that Hazard index values were included in Risk Class 1, with a very low hazard level. The order of Cancer Risk values is as follows, Cd < Cr < Ni < Pb. As a general conclusion, we can say that the samples can be intended for consumption by children and infants.

Heavy metals levels and associated health risk assessment of Euphorbia granulata Forssk

Medicinal plants are considered as the safest approach to treat various ailments. However, prolonged consumption of plants containing high levels of heavy metals (HMs) can lead to deleterious consequences. Euphorbia granulata (EG) is therapeutically used in Pakistan and many parts of the world. This study assessed EG from three districts of Khyber Pakhun Khwa, Pakistan, for the levels of seven HMs (Pb, Cd, Cr, Ni, Ag, Hg, and As) and the associated health risks. Non-carcinogenic health risk associated with HMs was assessed from hazard quotients (THQ) and hazard index (HI). THQ values of Hg for Peshawar (1.566) and Mardan (1.897) were above the safe recommended limits (< 1) of USEPA. Overall more than 80% of THQ was contributed by the Hg alone. Total cancer risk (TCR) was calculated using incremental lifetime cancer risk (ILCR). The hazard index (HI) displayed by Peshawar (1.87) and Mardan (2.7) samples indicated the potential adverse health effects due to EG. Furthermore, the TCR for Peshawar (2.2 × 10-4), Mardam (2.3 × 10-4), and Swat (1.4 × 10-4) was also more than US-EPA recommended threshold value (1 × 10-4). Our results unveiled the possibility of carcinogenic health risks with Pb, Cd, Cr, Ni, and As to EG consumers. Due to potential non-carcinogenic and carcinogenic health risk, chronic use of E. granulata is not recommended, particularly from HMs contaminated sites.

Assessing heavy metal contamination in soils using improved weighted index (IWI) and their associated human health risks in urban, wetland, and agricultural soils

Contamination of nine heavy metals (HMs) Zn, Pb, Cu, Cd, As, Co, Cr, Mo, and Ni in agricultural, urban, and wetland soils from Western and Rift Valley parts of Kenya was assessed using improved weighted index (IWI) and pollution loading index (PLI). Non-carcinogenic risks posed by the HMs were assessed using hazard quotients (HQ) and hazard index (HI), while carcinogenic risks were assessed using cancer risks (CR) and total cancer risks (TCR). The average concentration of Zn, Cr, Ni, Pb, Co, Cu, As, Mo, and Cd was 94.7 mg/kg, 43.6 mg/kg, 22.3 mg/kg, 21.0 mg/kg, 19.8 mg/kg, 18.0 mg/kg, 16.3 mg/kg, 1.83 mg/kg, and 1.16 mg/kg, respectively. IWI ranged from 0.57 to 6.04 and categorized 6.82% of the study sites as not polluted, 27.3% as slightly polluted, 43.2% as moderately polluted, and 22.7% as seriously polluted. PLI ranged from 0.38 to 3.95 and classified 15.9% of the sites as not polluted, 61.4% as slightly polluted, 20.5% as moderately polluted, and only 2.3% as seriously polluted. Wetlands retained more HMs from both urban and agricultural runoff and were therefore the most polluted. The heavy metals did not pose any risks via inhalation and dermal contact, but HQingestion for As for children was >1 in 2.3% of the sites studied. CR via ingestion and TCR for As were above the allowable limits for children and adults indicating high risks of cancer. Intensive agriculture and urbanization should be closely monitored to prevent further HM pollution.

Molecular characterization of stress tolerance genes associated with D. indicus strain under extreme environment conditions

Deinococcus indicus is a novel bacteria isolated from West Bengal, India known for its UV radiation and heavy metal tolerance. Since, this organism is reported from a region known for heavy metal contamination and earlier investigations demonstrated its radiation resistance, our study focused on the multiple stress responsive and DNA repair mechanisms. Though, most of the members of the genus Deinococcus are Gram positive cocci, D. indicus postures Gram negative rod shaped cells. Hence, the objectives were framed precisely to understand DNA repair pathway and stress responsive genes expression with a broader perspective. Based on available whole genome sequence of D. indicus, quantitative real time PCR (qPCR) was done to determine the expression pattern of multiple stress responsive genes upon various environmental extremities. Among them, UV responsive genes like UvrD and UvsE showed elevated expression when subjected to UV-C radiation at different time intervals. Similarly, when supplemented with arsenic and chromium, ArsR and ArsB exhibited considerably higher level of expression. While all the genes were subsequently analyzed in-silico, depicted that most of them were with N-glycosylation site, GPI anchor sites, N-terminal trans-membrane helix region besides putative signal peptides. Overall, this study opined the functional information on stress tolerance genes that aid to understand the DNA damage recovery mechanism towards elucidation of DNA repair pathways.

Arsenic-contaminated groundwater and its potential health risk: A case study in Long An and Tien Giang provinces of the Mekong Delta, Vietnam

The occurrence of arsenic (As) in groundwater (drilled well water) that were used for drinking, cooking, and personal hygiene and its risks to human health in Long An and Tien Giang provinces (Mekong delta, Vietnam) were evaluated in this study. The average As concentrations were 15.92 ± 11.4 μg/L (n = 24, Long An) and 4.95 ± 4.7 μg/L (n = 24, Tien Giang). The average concentrations of As in Long An had not reached the WHO and QCVN 01: 2009/BYT healthy drinking water standard (10 μg/L). When used as a source of water for drinking and daily activities, arsenic-contaminated groundwater may have a direct impact on human health. The risk assessment from groundwater established by the US Environmental Protection Agency (USEPA) was conducted. The risk assessment showed that the average cancer risk (CR) values were 8.68 × 10^-4 (adults) and 2.39 × 10^-3 (children) for Long An, and 2.70 × 10^-4 (adults) and 7.43 × 10^-4 (children) for Tien Giang. These results were significantly higher than the CR (1 × 10^-4) proposed by the USEPA. The adverse health effect was therefore specifically warned by the use of arsenic-contaminated groundwater. This research offers valuable knowledge for efficient water management approaches to guarantee local communities' health protection.

Spatial and temporal variation of dissolved heavy metals in the Lijiang River, China: implication of rainstorm on drinking water quality

Lijiang River is an essential drinking water source and natural scenery in the Guilin City. For the first time, implications of rainstorm were taken into consideration by investigating spatial and temporal variation of dissolved heavy metals (HMs) in the Lijiang River water. A total of 68 water samples were collected during low flow (normal) season and high flow (rainstorm) season from 34 sampling sites. Dissolved HMs including Cr, Mn, Co, Cu, Zn, As, Cd, Sb, and Pb were found to meet the respective drinking water standards, while comparatively higher concentration was observed after the rainstorm season, except for Cr. Multivariate statistical analysis showed that Co, Cu, Cr, Zn, Sb, and Pb in normal season were mainly controlled by anthropogenic sources. Furthermore, higher concentrations of Mn, Cu, Cd, Pb, Co, and Zn during the high flow season were attributed to rainstorm. The water quality index (WQI) showed good grades and comparatively lower in rainstorm season. The results of health risk assessment revealed that HMs in Lijiang River posed limited health risk; however, As posed potential health risk specially in rainstorm season. It is suggested to adopt preventive measures for mining activities and industrial waste-water discharge at the river's upstream and downstream.

Water quality assessment, multivariate analysis and human health risks of heavy metals in eight major lakes in Kenya

This study evaluates water quality, concentrations and health risks of heavy metals (HMs) in eight major lakes in Kenya namely Naivasha, Elementaita, Nakuru, Baringo, Bogoria, Turkana, Victoria and Magadi. Water quality was assessed using water quality index (WQI) and pollution evaluation index (PEI), while human health risk associated with ingestion and dermal contact of HMs was assessed using hazard quotients (HQ) and hazard index (HI). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to deduce the probable sources of the HMs. The average concentration of aluminium (Al), molybdenum (Mo), manganese (Mn), nickel (Ni), arsenic (As), zinc (Zn), selenium (Se), lead (Pb), chromium (Cr), mercury (Hg), cobalt (Co) and cadmium (Cd) in the eight lakes was 824.6, 66.1, 58.9, 16.2, 8.40, 7.84, 6.91, 4.65, 2.66, 0.86, 0.78 and 0.46, respectively, all in μg/L. Al, Mn, As, and Mo were relatively high in Rift Valley lakes and exceeded the maximum permissible levels for drinking water. Notably, high HM concentrations were recorded at the entry points of rivers and areas with high human activities. Lake Magadi had the highest average WQI of 158.8 followed by lake Elementaita (128.4), Bogoria (79.5), Nakuru (73.3), Turkana (57.6), Victoria (52.3), Baringo (42.6) and Naivasha (25.5). Lake Magadi also had the highest average PEI of 40.0 followed by Elementaita (30.1), Bogoria (16.2), Nakuru (15.7), Victoria (10.8), Baringo (9.57), Turkana (9.53) and Naivasha (5.12). Based on WQI, Lake Naivasha water was excellent for drinking, Lake Victoria, Turkana, Baringo, Nakuru, and Bogoria had good water, but water from Lake Elementaita and Magadi was of poor quality. PEI classified the lakes as minimally polluted except Lake Magadi. Multivariate analysis concluded that Pb, Cr, Ni and Se had anthropogenic sources, mainly agricultural and urban runoff, but other HMs had natural influence. Although the HMs did not pose any health risks through dermal contact, HQingestion was >1 for adults and children consuming water from Lake Elementaita, Nakuru, Bogoria and Magadi due to non-carcinogenic risks associated with As, Zn and Mo. These results are important for formulating the necessary remediation policies to improve water quality in the eight lakes.

Determination of Lead Level in Pasteurized Milk and Dairy Products Consumed In Tehran and Evaluation of Associated Health Risk

Background: Milk and dairy products are the main sources of essential nutrients particularly for children. However, milk and dairy products can be contaminated with chemical hazards and contaminants which pose serious health risks for consumers. These toxic compounds are entered into the food chain through contaminated soil, water, and air and their presence even at low levels would result in metabolic disorders. Objectives: The aim of this study was to determine the level of lead in pasteurized milk and different dairy products in high-consumed brands in Tehran. Methods: A total of 38 samples (18 pasteurized milk and 20 dairy products from the most-consumed brands) were analyzed using graphite furnace atomic absorption spectroscopy for quantification of lead level. Hazard quotient (HQ) and carcinogenic risk (CR) were used to assess health risk and carcinogenic risk. Results: The results showed that the levels of lead in all pasteurized milk samples and dairy products were below the allowable limit. HQ was less than 1 in all samples and CR was in the range of 10-8 to 10-7 and both were at acceptable levels. Conclusions: It can be concluded that there was no risk of carcinogenicity in pasteurized milk samples and dairy products for children and adults. However, due to the higher consumption of milk by children and their greater susceptibility, the level of heavy metals should be monitored by health agencies.

Improving the predictive value of bioaccessibility assays and their use to provide mechanistic insights into bioavailability for toxic metals/metalloids - A research prospectus

Widespread contamination of soil, dust, and food with toxic metal(loid)s pose a significant public health concern. Only a portion of orally ingested metal(loid) contaminants are bioavailable, which is defined as the fraction of ingested metal(loid)s absorbed across the gastrointestinal barrier and into systemic circulation. Bioaccessibility tools are a class of in vitro assays used as a surrogate to estimate risk of oral exposure and bioavailability. Although development and use of bioaccessibility tools have contributed to our understanding of the factors influencing oral bioavailability of metal(loid)s, some of these assays may lack data that support their use in decisions concerning adverse health risks and soil remediation. This review discusses the factors known to influence bioaccessibility of metal(loid) contaminants and evaluates experimental approaches and key findings of SW-846 Test Method 1340, Unified BARGE Method, Simulated Human Intestinal Microbial Ecosystem, Solubility Bioaccessibility Research Consortium assay, In Vitro Gastrointestinal model, TNO-Gastrointestinal Model, and Dutch National Institute for Public Health and the Environment bioaccessibility models which are used to assess oral absolute bioavailability and relative bioavailability in solid matrices. The aim of this review was to identify emerging knowledge gaps and research needs with an emphasis on research required to evaluate these models on (1) standardization of assay techniques and methodology, and (2) use of common criteria for assessing the performance of bioaccessibility models.

Environmental contamination by heavy metals and associated human health risk assessment: a case study of surface water in Gomti River Basin, India

The aim of the present study was to assess the status of heavy metal contamination and health risks associated with the use of water from River Gomti by millions of people. The value of the degree of contamination (C_d) was found to be '11.93', signifying 'high' risk levels due to heavy metal contamination in River Gomti across an approximate stretch of 61 km including upstream, midstream, and downstream locations of Lucknow city. The potential sources of heavy metal pollution in River Gomti include both sewage and industrial effluents, being transported by drains which overflow into the river. The heavy metals were found to have low mobility owing to the 'near neutral' pH of river water. The findings from the human health risk assessment revealed that the hazard index associated with non-carcinogenic risks exceeded the permissible limits at all sampling stations. The highest health risk was found at Bharwara sewage treatment plant discharge point, downstream of Lucknow city signifying the elevated levels of heavy metal in the river water post treatment from Bharwara STP. The results of carcinogenic risk assessment suggested that children were more susceptible to health risks, and immediate remedial measures are required to control the elevated levels of heavy metals at all the sampling stations.

Various Natural and Anthropogenic Factors Responsible for Water Quality Degradation: A Review

Recognition of sustainability issues around water resource consumption is gaining traction under global warming and land utilization complexities. These concerns increase the challenge of gaining an appropriate comprehension of the anthropogenic activities and natural processes, as well as how they influence the quality of surface water and groundwater systems. The characteristics of water resources cause difficulties in the comprehensive assessment regarding the source types, pathways, and pollutants behaviors. As the behavior and prediction of widely known contaminants in the water resources remain challenging, some new issues have developed regarding heavy metal pollutants. The main aim of this review is to focus on certain essential pollutants’ discharge from anthropogenic activities categorized based on land-use sectors such as industrial applications (solid/liquid wastes, chemical compounds, mining activities, spills, and leaks), urban development (municipal wastes, land use practices, and others), and agricultural practices (pesticides and fertilizers). Further, important pollutants released from natural processes classified based on climate change, natural disasters, geological factors, soil/matrix, and hyporheic exchange in the aquatic environment, are also discussed. Moreover, this study addresses the major inorganic substances (nitrogen, fluoride, and heavy metals concentrations). This study also emphasizes the necessity of transdisciplinary research and cross-border communication to achieve sustainable water quality using sound science, adaptable legislation, and management systems.

Fate of arsenic in living systems: Implications for sustainable and safe food chains

Arsenic, a group 1 carcinogen for humans, is abundant as compared to other trace elements in the environment and is present mainly in the Earth's crust and soil. The arsenic distributions in different geographical regions are dependent on their geological histories. Anthropogenic activities also contribute significantly to arsenic release into the environment. Arsenic presents several complications to humans, animals, and plants. The physiology of plants and their growth and development are affected by arsenic. Arsenic is known to cause cancer and several types of organ toxicity, such as cardiotoxicity, nephrotoxicity, and hepatotoxicity. In the environment, arsenic exists in variable forms both as inorganic and organic species. From arsenic containing compartments, plants can absorb and accumulate arsenic. Crops grown on these contaminated soils pose several-fold higher toxicity to humans compared with drinking water if arsenic enters the food chain. Information regarding arsenic transfer at different trophic levels in food chains has not been summarized until now. The present review focuses on the food chain perspective of arsenic, which affects all components of the food chain during its course. The circumstances that facilitate arsenic accumulation in flora and fauna, as components of the food chain, are outlined in this review.

Water intake meets the Water from inside the human body – physiological, cultural, and health perspectives - Synthetic and Systematic literature review

Background. The average adult human body of 70 kilograms consists in about 67.85% water distributed evenly to an average of 70 % in all major organs of the body: skin, muscles, brain, spinal cord, liver, heart, lungs, spleen, kidneys, pancreas and gastro-intestinal tract. A smaller percentage is found in the bones (30%), teeth (5%) and fat tissue (50%). Objective. This review article attempts to present different perspectives on the physiological properties of water in the human body. We describe from the ancient Chinese medicine theory about water being one of the 5 elements of nature and its harmonious interrelation with the other elements in order to balance the human body, to the successful experiments of researchers which demonstrated waters’ capability to change its molecular structure based on feelings, intentions and energy it was exposed to. We briefly describe the role of water for the human body and what effects can the lack of it have, especially dehydration with all the phases of severity. Also, we present the health benefits of drinking water and which type of water is best to consume. We shorty review the different types of natural mineral waters in Romania and the importance of the Romanian researches for balneology and how the waters cand be administrated in crenotherapy for different types of pathologies. Methods. To elaborate our systematic review, we have searched for relevant open access articles and review articles in ISI Web of Science, published from January 2017 until August 2021. The terms used were water AND health in the title. Articles were excluded in the second phase if they did not reach the relevance citation criterion. The eligible articles were analyzed in detail regarding water importance for human health. Results. Our search identified, first, 548 articles. After applying a PEDro like selection filter and, we selected 93 articles with a minimum of 8 points on our PEDro like filtering scale (good, very good, and excellent articles with a minimum of 5 citations per year). Detailed analysis of the 93 selected articles has conducted us to the elimination of 33 of them as being on a different subject than that of our article. To the 60 full articles retained for this systematic and synthetic article, we have added 10 articles found through a separate Google search, as being considered of high relevance for our subject and necessary to be included. Conclusions. Water is essential for the entire planet and also indispensable for the survival of the human body. Keywords: water intake, water balance, body water, water molecular structure, dehydration, crenotherapy

Human biomarkers associated with low concentrations of arsenic (As) and lead (Pb) in groundwater in agricultural areas of Thailand

Human biomarkers were used to evaluate the lead (Pb) and arsenic (As) exposure of local people who lived in an agricultural area with intense agrochemical usage and who consumed groundwater. Although the heavy metals/metalloids in the groundwater were at low concentrations, they could cause adverse effects due to a high daily water intake rate over the long term. Biomarkers (hair, fingernails and urine) were collected from 100 subjects along with the local shallow groundwater and tap water, which is the treated deep groundwater, and investigated for the concentrations of As and Pb. Shallow groundwater had an average pH of 5.21 ± 1.90, ranging from 3.77 to 8.34, with average concentrations of As and Pb of 1.311 µg/L and 6.882 µg/L, respectively. Tap water had an average pH of 5.24 ± 1.63, ranging from 3.86 to 8.89, with the average concentrations of As and Pb of 0.77 µg/L and 0.004 µg/L, respectively. The levels of both As and Pb in the hair, fingernails and urine of shallow groundwater-consuming residents were greater than those in the hair, fingernails and urine of tap water-consuming residents. Interestingly, the As level in urine showed a linear relationship with the As concentration in groundwater (R2 = 0.91). The average water consumption rate was approximately two-fold higher than the standard; thus, its consumption posed a health risk even at the low As and Pb levels in the groundwater. The hazard index (HI) ranged from 0.01 to 16.34 (average of 1.20 ± 2.50), which was higher than the acceptable level. Finally, the concomitant factors for As and Pb in the urine, hair and nails from both binary logistic regression and odds ratio (OR) analysis indicated that groundwater consumption was the major concomitant risk factor. This study suggested that direct consumption of this groundwater should be avoided and that the groundwater should be treated, especially before consumption. In conclusion, urine is suggested to be a biomarker of daily exposure to As and Pb, while for long-term exposure to these metals, fingernails are suggested as a better biomarker than hair.

Temporal variation of leachate pollution index of Indian landfill sites and associated human health risk

The present study investigated the variation in leachate pollution index (LPI) of four municipal solid waste (MSW) dumping sites: non-engineered (Okhla, Ghazipur, Bhalswa) and engineered (Narela-Bawana) of Delhi, India. A review of 142 screened studies from Google Scholar database was done for synthesis of information on LPI parameters. Further, the rate constant determination and human health risk assessment for various leachate parameters was done. Results showed the following LPI trends: Okhla landfill: irregular with exceedance to threshold value; Bhalswa landfill: exponential increase; and Narela-Bawana landfill: linear increase. Parameters such as pH, dissolved solids, copper, nickel, zinc, and chromium of Bhalswa landfill, exhibited an exponential decay with LPI variation. Whereas, for Narela-Bawana's leachate BOD and COD parameters, an exponential decay in LPI vs zinc and linear increase for LPI vs lead was observed. For all dumping sites, a positive correlation was observed between heavy metals and LPI. In case of human health risk assessment, order of oral risk posed by Okhla's metals was cadmium > chromium > nickel > lead, with maximum hazard quotient (HQ) of 1.61 for cadmium. For Ghazipur and Bhalswa landfills, cancer risk values for both adult and child sub-populations were observed to be maximum for cadmium followed by nickel, chromium, and minimum for lead. For Narela-Bawana landfill, the order of cancer risk was as follows: chromium > nickel > lead. HQ for Pb-contaminated groundwater exceeded the threshold limit in Ghazipur and Bhalswa landfills. For dermal groundwater exposure, cadmium for Okhla (adult 2.3 × 10^-4 and child 1.4 × 10^-4), Ghazipur (adult 9 × 10^-5 and child 5.2 × 10^-5), and Bhalswa (adult 1.5 × 10^-4 and child 8.6 × 10^-5) was observed to have maximum cancer risk. The analyzed year-wise LPI trend, calculated rate constants, and human health risk values from present study provide a basis to waste managers and regulators for understanding various waste sources.

Increased urinary arsenic concentration in newly diagnosed type 2 diabetes mellitus: a gender-independent, smoking-dependent exposure biomarker in older adults in Tehran

Arsenic is ranked in the top ten environmental toxicants but its impact on type 2 diabetes mellitus (T2DM) and its association with other human health effects is contradictory. We aimed in this study to compare the urinary arsenic concentration (u As) in older age adults (> 40 years) and their T2DM subgroup in an age and gender-matched case control study to find the association of u As with, diet, oxidative stress, smoking, anthropometric factors, and lifestyle in our study participants. Face-to-face interviews based on structured questionnaires were conducted on 200 female and male volunteers (100 cases and 100 control). Considering the exclusion criteria, u As concentration and serum biomarkers of oxidative stress (malondialdehyde, superoxide dismutase, catalase) of 30 newly diagnosed T2DM and 30 control were determined by ICP-mass analysis and ELISA reader respectively. Despite the similarities in sociodemographic, diet, and lifestyle factors in males and females and their T2DM subgroups, a 4 times difference in u As levels between T2DM (93.7 ng/L (32)) and their healthy counterparts (23.7 ng/L (2.3)) without meaningful associations with gender, age, BMI, diet, and lifestyle was observed. Mean u As concentration in total population of smokers was significantly higher than non-smokers ((119 ng/L vs. 22.5 ng/L (p = 0.03)) and oxidative stress markers were not significantly higher in T2DM smokers than non-smokers. Chronic arsenic exposure through smoking could be contributed to the incidence of T2DM in older age adults. Oxidative stress markers were not significantly increased in smoker subgroup compared with non-smokers but except smoking pattern, other variables did not affect u As concentration. Precautionary measure to reduce the exposure of people with this element is recommended to prevent the arsenic-induced T2DM in human populations.

Presence of heavy metals in drinking water resources of Iran: a systematic review and meta-analysis

Water quality is one of the most important indices for public health especially for drinking water consumptions. This study was conducted to survey the presence of heavy metals in drinking water resources of Iran using a systematic review and meta-analysis. The literature search was conducted in data bases of PubMed, Web of Science, EMBASE, Scopus, Google Scholar, and some Persian databases up to 31 July 2018. Of all the articles reviewed (1151 articles), 61 papers were eligible for systematic review. Results indicated variable heterogeneity between studies for different pollutants (I² between 0 and 100). A subgroup analysis was performed for three different types of water resources such as drinking water, groundwater, and surface water to find the possible source of the heterogeneity. The pooled mean concentration level of iron was the highest at 255.8 (95% CI = 79.48-432.13 μg/l) and vanadium the lowest at 3.21 (95% CI = 1.45-4.98 μg/l). The sequence of metal concentration (μg/l) in descending order is as follows: Fe (255.8) > B (159.81) > Al (158.5) > Zn (130.73) > As (85.85) > Mn (51.61) > Cu (47.98) > Se (42.68) > Pb (37.22) > Co (22.76) > Mo (18.92) > Ni (16.79) > Cr (13.47) > Hg (4.49) > Cd (4.19) > V (3.21). The mean pooled concentration level of Al, As, Se, Pb, and Cd was higher than the WHO guideline and Iran Standard, and the rest of the metals had lower mean pooled concentration level. Pb and Cd were the common heavy metals that existed in all subgroups. As a recommendation, the relationship assessment of water parameters and heavy metals could be addressed in future studies of Iran's water resources.

Distribution and health risk assessment of trace elements in ground/surface water of Kot Addu, Punjab, Pakistan: a multivariate analysis

Water is a key component for living beings to sustain life and for socio-economic development. Anthropogenic activities contribute significantly to ground/surface water contamination particularly with trace elements. The present study was designed to evaluate distribution and health risk assessment of trace elements in ground/surface water of the previously unexplored area, Tehsil Kot Addu, Southern-Punjab, Pakistan. Ground/surface water samples (n = 120) were collected from rural and urban areas of Kot Addu. The samples were analyzed for physicochemical characteristics: total dissolved solids (TDS), pH, and EC (electrical conductivity), cations, anions, and trace elements particularly arsenic (As), lead (Pb), cadmium (Cd), and zinc (Zn). All of the water characteristics were evaluated based on the water quality standards set by World Health Organization (WHO). Results revealed the suitability of water for drinking purpose with respect to physicochemical attributes. However, the alarming levels of trace elements especially As, Cd, and Pb make it unfit for drinking purpose. Noticeably, 23, 96, and 98% of water samples showed As, Cd, and Pb concentrations higher than the permissible limits. Overall, the estimated carcinogenic and non-carcinogenic risk to the exposed community was higher than the safety level of USEPA, suggesting the probability of cancer and other diseases through long-term exposure via ingestion routes. Therefore, this study demonstrated an urgent need for water filtration/purification techniques, and some quality control measures are warranted to protect the health of the exposed community in Tehsil Kot Addu.

Determination and health risk assessment of trace elements in the tap water of two Sub-Cities of Addis Ababa, Ethiopia

Water is an essential component of all living things on earth and the contamination of water by heavy metals can cause detrimental health effects. This study aimed to determine the health risk posed by trace elements (Fe, Zn, Cu, Mn, Ni, Cr, Cd, Co, Pb, and As) present in the drinking water supplies of Gullele and Akaki-Kality Sub-Cities, upstream and downstream parts of Addis Ababa, respectively. The concentrations of the potentially toxic trace elements in the water samples were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). The highest concentration of the heavy metals was observed for Iron. Cadmium and cobalt were not detected in any of the tap water samples. Samples from Gullele contained higher levels of Fe and Mn, 220.3 ± 0.17 and 19.78 ± 0.08 μg/L, respectively compared to Akaki-Kality, 38.87 ± 0.14 and 2.08 ± 0.01 μg/L, respectively. Conversely, tap water from Akaki-Kality contained significantly higher levels of As than that from Gullele. Additionally, Cr and Ni were detected only in samples from Akaki-Kality, which might be due to the various industries in the area. The highest incremental lifetime cancer risk was found for arsenic, with values for children and adults in Akaki-Kality 2.50 × 10-4 and 4.50 × 10-4, respectively. Likewise, in Gullele Sub-City, it was 5.00 × 10-5 and 1.00 × 10-4 for adults and children, respectively. The results indicate that carcinogenic risk occurrence is probable from As in both studied areas.

Heavy Metals in Acrylic Color Paints Intended for the School Children Use: A Potential Threat to the Children of Early Age

Heavy metals are the harmful elements, regarded as carcinogens. Nevertheless, owing to their physical and chemical properties, they are still used in the production of several commercial products. Utilization of such products increases the chance for the exposure of heavy metals, some of them are categorized as probable human carcinogens (Group 1) by the International Agency for Research on Cancer. Exposure of heavy metals to school children at early age can result severe life time health issues and high chance of emerging cancer. Thus, we have performed study relating to the presence of heavy metals in acrylic color paints commonly used by the school children. Acrylic paints of different colors were assayed for seven potential heavy metals manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) using microwave digestion and iCAPQ inductively coupled plasma mass spectrometry (ICP-MS) system. The optimized method including paints digestion reagents nitric acid (HNO3, 65%, 5 mL) and hydrofluoric acid (HF, 40%, 2 mL) have offered excellent method performance with recovery values ranged between 99.33% and 105.67%. The elements were identified in all of the analyzed samples with concentrations ranged from 0.05 to 372.59 µg/g. Cd constitutes the lower percentage (0.05%), whereas Zn constitutes high ratio contribution which was tremendously high (68.33%). Besides, the paints contamination was also color specific, with considerably total heavy metal concentrations found in brunt umber (526.57 µg/g) while scarlet color (12.62 µg/g) contained lower amounts. The outcomes of our investigation highlight the necessity for guidelines addressing the heavy metals in acrylic color paints intended for the school children usage.

Physico-chemical properties and reactive oxygen species generation by respirable coal dust: Implication for human health risk assessment

This study investigates the mineralogy, micro-morphology, chemical characteristics and oxidation toxicity of respirable dusts generated in underground coal mines. The active sampling was applied to collect airborne particulates with aerodynamic diameter <4 µm (PM₄) at depth greater than 500 m from earth surface. The average mass concentration of PM₄ was extremely higher than recommended values. QXRD and FESEM-EDS analyses were applied to study the micro-mineralogy and micro-morphology of respirable dusts. The chemical analysis by ICP-MS revealed an enrichment of V, Cr, Cu, Zn, As, Ag, Cd and Sb in respirable dust compared with the background environment and world coals. The EPA's health risk model showed that the health risk posed by Cr and Co in all workplaces exceeded the acceptable risk value for human health. The synthetic respiratory tract lining fluid (RTLF) model was utilized to achieve a novel insight into the toxicity of respirable coal dust. The result showed an overall depletion of lung surface antioxidants with the decreasing trend of ascorbic acid > reduced glutathione >> urate, implying low- to medium level of oxidative stress. The result of this study can be applied globally by decision-makers to decrease hazardous exposure of mine workers to respirable dust.

Effects of arsenic exposure on lipid metabolism: a systematic review and meta-analysis

Lipid metabolism dysfunction is a risk factor for cardiovascular diseases. Reportedly, arsenic exposure could affect lipid metabolism, but this finding remains controversial. Herein, we updated and reevaluated evidence regarding the relationship between arsenic exposure and lipid metabolism. Electronic and manual searches were performed to determine the effect of arsenic exposure on lipid metabolism from inception up to 30 November 2019. Overall, five studies were included in our meta-analysis. Two reviewers independently extracted information. Standardized mean difference (SMD) and 95% confidence intervals (CI) were used to analyze the combined effects of four indicators related to lipid metabolism (total cholesterol [TC], triglyceride [TG], high-density lipoprotein [HDL], low-density lipoprotein [LDL]). Afterwards, subgroup and sensitivity analyses were performed to explore the source of heterogeneity. Publication bias was tested using funnel plots and Begg's test. In this study, we observed that arsenic exposure can affect lipid metabolism by reducing serum HDL levels and increasing serum LDL levels. Following subgroup analysis, the arsenic concentration appeared to affect lipid metabolism. Funnel plot and Begg's test suggested no asymmetry. In conclusion, we recommend that potential influencing factors, including age, exposure time, and multiple concentration gradients, should be considered to further explore the relationship between arsenic exposure and lipid metabolism.

Heavy Metal Contaminations in Herbal Medicines: Determination, Comprehensive Risk Assessments, and Solutions

Heavy metal contamination in herbal medicines is a global threat to human beings especially at levels above known threshold concentrations. The concentrations of five heavy metals cadmium (Cd), lead (Pb), arsenic (As), mercury (Hg) and copper (Cu) were investigated using Inductively Coupled Plasma Optical Mass Spectrometry (ICP-MS) with 1773 samples around the world. According to Chinese Pharmacopoeia, 30.51% (541) samples were detected with at least one over-limit metal. The over-limit ratio for Pb was 5.75% (102), Cd at 4.96% (88), As at 4.17% (74), Hg at 3.78% (67), and of Cu, 1.75% (31). For exposure assessment, Pb, Cd, As, and Hg have resulted in higher than acceptable risks in 25 kinds of herbs. The maximal Estimated Daily Intake of Pb in seven herbs, of Cd in five, of Hg in four, and As in three exceeded their corresponding Provisional Tolerable Daily Intakes. In total 25 kinds of herbs present an unacceptable risk as assessed with the Hazard Quotient or Hazard Index. Additionally, the carcinogenic risks were all under acceptable limits. Notably, As posed the highest risk in all indicators including Estimated Daily Intake, Hazard Index, and carcinogenic risks. Therefore further study on enrichment effect of different states of As and special attention to monitoring shall be placed on As related contamination.

Health Risk Assessment of Heavy Metals in Groundwater of Industrial Township Virudhunagar, Tamil Nadu, India

The present investigation deals with the health risk assessment due to the heavy metals (Cd, Cr, Cu, Co, Mn, Pb, Ni, and Zn) in groundwater in the industrial township of Virudhunagar district. Twenty groundwater samples were collected, and the measured concentration of the heavy metals follows the order Pb > Ni > Zn > Co > Cr > Cd > Cu > Mn. The metal pollution indices (heavy metal evaluation index, Heavy metal pollution index, degree of contamination) were calculated using the measured heavy metal concentrations. The samples collected nearer to the industrial zone have elevated concentrations of Pb, Cd, and Ni. The carcinogenic and noncarcinogenic risks were calculated based on the measured heavy metals concentration and average daily intake of water. The calculated carcinogenic risk values (5.66 × 10^-3-1.56 × 10^-2) (Pb, Cd, and Ni) exceed the acceptable limit of 10^-6-10^-4. The noncarcinogenic risk exceeds the acceptable limit of one for the heavy metals Pb and Cr. The higher carcinogenic and noncarcinogenic risk values reveal that the study area has health risks due to Pb, Cd, Ni, and Cr metals. Furthermore, factor analysis and cluster analysis showed that the industrial impact and wastage dumpsites are the prime sources for heavy metal contamination in groundwater of the study area.

Arsenic-induced changes in miRNA expression in cancer and other diseases

miRNAs (miRNA) are essential players regulating gene expression affecting cellular processes contributing to disease development. Dysregulated miRNA expression has been observed in numerous diseases including hepatitis, cardiovascular diseases and cancers. In cardiovascular diseases, several miRNAs function as mediators of pathogenic stress-related signaling pathways that may lead to an excessive extracellular matrix production and collagen deposition causing cardiac stress resulting in fibrosis. In cancers, many miRNAs function as oncogenes or tumor suppressors facilitating tumor growth, invasion and angiogenesis. Furthermore, the association between distinct miRNA profile and tumor development, progression and treatment response has identified miRNAs as potential biomarkers for disease diagnosis and prognosis. Growing evidence demonstrates changes in miRNA expression levels in experimental settings or observational studies associated with environmental chemical exposures such as arsenic. Arsenic is one of the most well-known human carcinogens. Long-term exposure through drinking water increases risk of developing skin, lung and urinary bladder cancers, as well as cardiovascular disease. The mechanism(s) by which arsenic causes disease remains elusive. Proposed mechanisms include miRNA dysregulation. Epidemiological studies identified differential miRNA expression between arsenic-exposed and non-exposed individuals from India, Bangladesh, China and Mexico. In vivo and in vitro studies have shown that miRNAs are critically involved in arsenic-induced malignant transformation. Few studies analyzed miRNAs in other diseases associated with arsenic exposure. Importantly, there is no consensus on a consistent miRNA profile for arsenic-induced cancers because most studies analyze only particular miRNAs. Identifying miRNA expression changes common among humans, rodents and cell lines might guide future miRNA investigations.

Health Risk Evaluation of Trace Elements in Geophagic Kaolinitic Clays within Eastern Dahomey and Niger Delta Basins, Nigeria

The deliberate consumption of earthly materials is a universally recognised habit with health benefits and risks to those that practice it. Thirteen (13) samples comprising of six (6) Cretaceous and seven (7) Paleogene/Neogene geophagic kaolinitic materials, respectively, were collected and analysed for trace element concentrations (V, Cr, Co, Ni, Zn, Pb, and Fe), and possible risk on consumers' health. The trace element compositions were obtained using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and X-ray fluorescence spectrometry (XRF) analytical methods. Based on their average concentrations, Fe > V > Cr > Ni > Zn > Pb > Cu > Co and Fe > V > Cr > Zn > Cu > Pb > Ni > Co for the Cretaceous and Paleogene/Neogene geophagic clays, respectively. Iron concentrations were significantly higher in Paleogene/Neogene geophagic clays than in Cretaceous geophagic clays. The nutritional value of Cu and Zn were lower whereas, Cr and Fe were higher than the recommended dietary intake. The index of geoaccumulation (0 < Igeo ≤ 1) showed that the geophagic materials were uncontaminated to moderately contaminated by the trace elements. The overall hazard indices (HI) for non-carcinogenic effects showed that the geophagic clays pose threat to children (HI > 1) and no threat to adults (HI < 1) health. However, the carcinogenic risk indices (CRI) for Cr, Ni, and Pb were within acceptable cancer risks (10-6 < CRI < 10-4) for children and adults. Hence, based on the trace element s HI and CRI, this study concluded that the consumption of Cretaceous and Paleogene/Neogene geophagic kaolinitic clays poses no risks to adult health but children might suffer health risk if the geophagic clays are not beneficiated before ingestion.

Individual species and cumulative mixture relationships of 24-hour urine metal concentrations with DNA methylation age variables in older men

BACKGROUND

Globally, toxic metal exposures are a well-recognized risk factor for many adverse health outcomes. DNA methylation-based measures of biological aging are predictive of disease, but have poorly understood relationships with metal exposures.

OBJECTIVE

We performed a pilot study examining the relationships of 24-h urine metal concentrations with three novel DNA methylation-based measures of biological aging: DNAmAge, GrimAge, and PhenoAge.

METHODS

We utilized a previously established urine panel of five common metals [arsenic (As), cadmium (Cd), lead (Pb), manganese (Mn), and mercury (Hg)] found in a subset of the elderly US Veterans Affairs Normative Aging Study cohort (N = 48). The measures of DNA methylation-based biological age were calculated using CpG sites on the Illumina HumanMethylation450 BeadChip. Bayesian Kernel Machine Regression (BKMR) was used to determine metals most important to the aging outcomes and the relationship of the cumulative metal mixture with the outcomes. Individual relationships of important metals with the biological aging outcomes were modeled using fully-adjusted linear models controlling for chronological age, renal function, and lifestyle/environmental factors.

RESULTS

Mn was selected as important to PhenoAge. A 1 ng/mL increase in urine Mn was associated with a 9.93-year increase in PhenoAge (95%CI: 1.24, 18.61, p = 0.03). The cumulative urine metal mixture was associated with increases in PhenoAge. Compared to a model where each metal in the mixture is set to its 50th percentile value, every one-unit increase of the cumulative mixture with each metal at its 70th percentile was associated with a 2.53-year increase in PhenoAge (95%CI: 0.10, 4.96, P<0.05).

CONCLUSION

Our results add novel evidence that metals detected in urine are associated with increases in biological aging and suggest that these DNA methylation-based measures may be useful for identifying individuals at-risk for diseases related to toxic metal exposures. Further research is necessary to confirm these findings more broadly.

Adsorptive removal of heavy metal ions using graphene-based nanomaterials: Toxicity, roles of functional groups and mechanisms

The endless introduction of toxic heavy metals through industrialization has worsened the heavy metal pollution in the environment. Thus, the need for its effective removal has become more crucial than before. Studies on graphene-based nanomaterials and their use in removing heavy metals are gaining tremendous traction over the past decade. The properties of graphene oxide (GO), such as large surface areas, desired functional groups and excellent mechanical properties are advantageous. Nevertheless, due to its tendency to agglomerate and difficulty in phase separation after treatment, the functionalization of GO using various materials of different surface functional groups is an ongoing study. The surface modification of GO is done by using various materials to introduce heteroatoms, which have high affinity for heavy metals. This review summarizes the utilization of different surface functional groups, such as oxygen-containing, nitrogen-containing, and sulphur-containing functionalized graphene oxide composites in the adsorption of cationic and oxyanionic heavy metals. The toxicity of these heavy metals is also addressed. Furthermore, the interactions between adsorbents and heavy metals which are influenced by pH and surface functional groups, are also discussed in detail. This is followed by the review in adsorption isotherms and kinetics. Future research needs are also offered.

Chromium, Cadmium, Lead, and Arsenic Concentrations in Water, Vegetables, and Seafood Consumed in a Coastal Area in Northern Vietnam

BACKGROUND

Heavy metal contamination and related risks for the environment and human health are matters of increasing concern.

METHODS

The levels of 4 heavy metals (Cr, Cd, Pb, and As) were evaluated in 2 water types (surface and well), 4 types of seafood (tiger shrimp, stuffed snail, snake-head fish, and catfish), and 27 types of vegetables (12 leafy vegetables, 4 pea plants, 4 tuber vegetables, and 7 herbs) that are commonly consumed in northern coastal communes located in Vietnam. Atomic absorption spectrometry was employed for quantification.

RESULTS

The mean concentrations of heavy metals detected in water, seafood, and vegetable samples exceeded the national permitted standards and World Health Organization (WHO) recommendation values by at least 2-fold, 2.5-fold, and 5-fold for surface water, vegetables, and well water, respectively. The concentrations of all 4 heavy metals detected in seafood samples were higher than the standards. The levels of heavy metals decreased with increasing distance between the sample collection point and the pollution source.

CONCLUSIONS

This is the first report of heavy metal contamination of common sources of food and water in the northern coastal area of Vietnam. Significantly, the concentrations of heavy metals detected in study samples exceeded the regulatory limits. These results underscore the importance of continued monitoring and the development of intervention measures to ensure that the quality of food and water meets established standards and protects the health of the local population.

Quality and safety of municipal drinking water in Addis Ababa City, Ethiopia

BACKGROUND

In low resourced countries, water-associated diseases have still impact on public health. Poor quality of water can cause waterborne diseases through bacteria, viruses, protozoa, and parasites that has been responsible for millions of morbidity and mortality. Therefore, this study aimed to assess quality and safety of public municipal drinking water in Addis Ababa City.

METHODS

Descriptive epidemiological study design that used quantitative approach was carried out at Addis Ababa City Administration from June 2016 to October 2016. Pre-tested and standardized aseptic sample collection technique was utilized to collect a total of 2976 samples (2951 water samples for bacteriological analysis by Presence-Absence (P-A) culturing method and 25 samples for parasites identification through direct microscopy examination). Descriptive data were summarized and cleaned by the SPSS version 20 software and presented in table and graph.

RESULTS

The study revealed that 10%, 7% and 3% were positive for bacteriological, total coliforms, and fecal coliforms respectively through Presence-Absence Broth test. The bacterial distribution trends from 1st to 13th weeks of wet season were slight increment of total coliforms and slight decrement for fecal coliforms. All tested for parasitological samples from selected reservoirs were free from parasitological species.

CONCLUSION

This study reflects that there were positive for bacterial, total coliforms, and fecal coliforms during the study period. It needs continuous screening and treating water sources to utmost important for prevention and control waterborne disease.