Metal Concentrations In Water Research Articles

The impact of heavy metals in water from abandoned mine on human health

The present study was conducted to investigate the heavy metal (Mn, Cu, Zn, As, and Cd) concentration of surface water in Smolnik creek in Slovakia. Furthermore, the study was aimed to determine the potential environmental health risk that the heavy metal concentration poses to the public. The values of the ecological potential index for the water in the study area were more than 600, reflecting a very high risk from the water body posed by these metals. Thus, this was also the reason to examine the impact of these heavy metals on the health of the population. Based on the heavy metal concentration, health risk assessments such as the chronic daily intake and hazard quotient (HQ) were calculated. Results showed that the daily intake of the heavy metals from all five samples taken from Smolnik creek was lower among adults than among children for two pathways of exposure. The non-carcinogenic hazard quotients of heavy metals in the studied area were higher among adults than among children. At all five sites, the HQ values for dermal exposure for adults were higher than 1. The HQ values for exposure through ingestion for adults and children were higher than 10 for almost all sites, indicating a disaster situation.

The Amount of Selected Heavy Metals in Water, Sediments and Fish Species from the Rupsha River, Khulna, Bangladesh

The present study was conducted to figure out the heavy metals (Cd, Co, Cu, Fe, Hg, Mn, Mo, Ni, Pb and Zn) concentrations in water, sediments and fish species from the Rupsha River, Khulna, Bangladesh to spot the heavy metal contamination level. Heavy metals are dangerous because they're non-biodegradable and having an extended half-life period. The heavy metal contamination could also be an excellent concern, especially for aquatic life. The metal concentration within the water sample from the Rupsha River was significantly above the rule values of WHO and USEPA respectively. Moreover, the concentration of metal within the sediments was also greater than the respective probable effect concentrations of the sediment quality guidelines. Furthermore, consistent with the fish standards, these studied fish species weren't found to be contaminated by heavy metals. It’s concluded that each of the heavy metals from the whole sample didn't exceed the standard maximum level. This study demonstrated that water of Rupsha River isn't safe for aquatic organisms also like humans in terms of Pb, Cd and Cr contents as accumulated through consumption.

Evaluation of Potential Health Risk, Heavy Metal Pollution Indices and Water Quality of Edku Lagoon- Egypt

Edku lagoon is one of the important aquaculture sectors in the Nile Delta of Egypt. Recently, the lagoon has become a sink of discharge wastewater from different anthropogenic sources. The present work aims to study physicochemical parameters, level of nutrients and heavy metal concentrations in water of the lagoon to assess the water quality and identify the potential pollution source(s). Water quality index (WQI), eutrophication index and multiple heavy metal pollution indices (HPI, HEI, PI and Cd) in addition to evaluation of human health risk (HQdermal) model were applied. The obtained data revealed that physicochemical parameter varied between 7.62 - 8.90 for pH, 1.2 – 12.2 g/l for salinity, 3.5 – 12.5 mg/l for dissolved oxygen, 1.3 – 1.9 mg/l for ammonia, 0.065 – 0.191 mg/l for nitrite, 0.217 – 0.915 mg/l nitrate, 0.198 – 0.527 mg/l for orthophosphate, and 51.32 – 102.7 μg/l for chlorophyll-a. The average concentrations of heavy metals were 0.439, 0.322, 0.290, 0.328, 0.059, 0.040, 0.00005 ppm for Fe, Mn, Zn, Cu, Pb, Cd and Hg, respectively. Based on WQI, the lagoon was classified as bad water, while EI result varied between eutrophic to mesotrophic. The pollution indices revealed to lagoon water is highly contaminated based on HPI, HEI and Cd and varied between slightly affected to seriously affected by heavy metals according to PI. Human health risk showed that, HQdermal for all metals except Cd lower than the unity.

Radiological and heavy metals analysis in soil and water at the former tin mining site in the urban area (Danau Kota Lake, Kuala Lumpur)

Former mining sites are known to be concentrated with enriched naturally occurring radioactive materials (NORM) and heavy metals, as a result of past mining activities. A number of the sites are reclaimed as an open area, which in turn raised concerns regarding public safety. Thus, it is crucial to evaluate the safety of the public engaging in activities around the former tin mining areas. A study is carried out to determine the concentrations of NORM and heavy metals in soil and water collected from Danau Kota Lake, Kuala Lumpur, known as a former mining site. Both NORM and heavy metals were analysed using gamma spectrometry and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The average concentration of 226Ra and 232Th in water collected was 0.7 ± 0.2 Bq/L and 0.1 ± 0.03 Bq/L, respectively. 40K, however, was not detected in the water. The average activity concentration of 226Ra, 232Th, and 40K in soil was 60.8 ± 2.3 Bq/kg, 42.9 ± 1.4 Bq/kg, and 338.4 ± 11.7 Bq/kg, respectively. From the values obtained, it is observed that the activity concentrations for both soil and water are still within the range limit reported by WHO and UNSCEAR. In regards to heavy metals analysis, manganese concentration was the highest in both water and soil with a value of 1.18 µg/L and 147.7 mg/kg, respectively. To evaluate the radiological hazard, the radium equivalent activity index (Req), gamma index (Iγ), absorbed dose rate (D), effective dose rate (Deff) and external hazard index (Hex) are calculated and valued at 148 Bq/kg, 1.1 Bq/kg, 69 nGy/h, 0.1 mSv/year and 0.4, respectively. All radiological hazard indices are found to be below the safety limits. Therefore, the lake area is considered safe for public activities except for Iγ.

Bioaccumulation and Toxicity of Cadmium, Copper, Nickel, and Zinc and Their Mixtures to Aquatic Insect Communities.

We describe 2 artificial stream experiments that exposed aquatic insect communities to zinc (Zn), copper (Cu), and cadmium (year 2014) and to Zn, Cu, and nickel (year 2015). The testing strategy was to concurrently expose insect communities to single metals and mixtures. Single‐metal tests were repeated to evaluate the reproducibility of the methods and year‐to‐year variability. Metals were strongly accumulated in sediments, periphyton, and insect (caddisfly) tissues, with the highest concentrations occurring in periphyton. Sensitive mayflies declined in metal treatments, and effect concentrations could be predicted effectively from metal concentrations in either periphyton or water. Most responses were similar in the replicated tests, but median effect concentration values for the mayfly Rhithrogena sp. varied 20‐fold between the tests, emphasizing the difficulty comparing sensitivities across studies and the value of repeated testing. Relative to the single‐metal responses, the toxicity of the mixtures was either approximately additive or less than additive when calculated as the product of individual responses (response addition). However, even less‐than‐additive relative responses were sometimes greater than responses to similar concentrations tested singly. The ternary mixtures resulted in mayfly declines at concentrations that caused no declines in the concurrent single‐metal tests. When updating species‐sensitivity distributions (SSDs) with these results, the mayfly responses were among the most sensitive 10th percentile of available data for all 4 metals, refuting older literature placing mayflies in the insensitive portion of metal SSDs. Testing translocated aquatic insect communities in 30‐d artificial streams is an efficient approach to generate multiple species effect values under quasi‐natural conditions that are relevant to natural streams. Environ Toxicol Chem 2020;39:812–833. Published 2020 Wiley Periodicals, Inc. on behalf of SETAC. This article is a US government work, and as such, is in the public domain in the United States of America.

Assessment and source quantification of heavy metal(loid)s in surface water using multivariate analyses from the Saigon River, Vietnam.

The metal concentration in surface water of a river could be affected by season, position, and oceanic process such as tide. The current study aimed to (1) examine the heavy metal(loid) concentration in surface water from the Saigon River as affected by the combination of season, tide, and position and (2) apportion and quantify pollution sources. Ninety-six surface water samples were collected from 13 sites on the River in four campaigns (rainy season + ebb tide, rainy season + flood tide, dry season + ebb tide, and dry season + flood tide). Eight heavy metal(loid)s (Al, B, Bi, Fe, Mn, Pb, Sr, and Zn) were measured and subjected to multivariate analyses. Three-way ANOVA showed that in the rainy season, the total concentration of the metal(loid)s (TCM) in two tides was not clearly different from each other while in the dry season the TCM was significantly higher during the ebb tide than during the flood tide. Principal component analysis/factor analysis and Pearson correlation matrix showed that the TCM could be derived from three main sources, grouped into anthropogenic activities such as industrial, agricultural, and domestic wastes from inside Ho Chi Minh city, and natural origins from lowland area and acid sulfate soil. Three pollution sources explained 70% and 68% of the total variance of TCM in the rainy and dry seasons, respectively. In brief, the metal(loid) concentration was significantly affected by the season and tide and the pollution sources could be derived from inside Ho Chi Minh City and from lowland areas beyond the river estuary.

Distribution and mobilization of heavy metals at an acid mine drainage affected region in South China, a post-remediation study

Dabaoshan Mine Site (DMS) is the largest polymetallic mine in South China. The Hengshi River flowing next to DMS receives acid mine wastes leaching from the tailings pond and run-off from a treatment plant, which flows into the Wengjiang River. This study focuses on spatiotemporal distribution and mobilization of As, Cd, Pb, and Zn along the Hengshi River, groundwater, fluvial sediments, and soils, with a focus on As due to its high toxicity and the fact that mining is one of the main sources of contamination. Geochemical analyses (heavy metals, grain-size, X-ray diffraction, organic carbon and sulfur content) followed by geochemical modeling (PHREEQC) and statistical assessment were done to determine the physicochemical characteristics, toxicity risks, and behavior of heavy metals. Near the tailings pond, heavy metal concentrations in surface water were 2–100 times higher than the Chinese surface water standard for agriculture. Although water quality during the dry season has improved since the wastewater treatment plant started, heavy metal concentrations were high during rainy season. In groundwater, heavy metal concentrations were low and pose little risks. Soils along the Hengshi River were disturbed and they did not show any specific trends. The potential ecological risk of heavy metals was ranked as Cd > As > Cu > Pb > Zn in sediments and Cd > Cu > Pb > As > Zn in soils indicating multi-metal contamination and toxicity. As(III) was the predominant species in surface water during the dry season, whereas As(V) dominated during the rainy season. Arsenic levels in most sites exceeded the Chinese soil standard. Although As is assumed to have a moderate ecological risk in sediments and low risk in soils, anthropogenic activities, such as mining and land-use changes contribute to the release of As and other heavy metals and pose a risk for local residents.

Trace metals in the water and margin sediments of the Rio Doce Basin in Linhares municipality, ES, Brazil

The Rio Doce Basin (DRB) is the largest freshwater source in Espírito Santo (ES) state, Brazil. In November 2015, the disruption of the iron tailings dam in the Mariana municipality, Minas Gerais state, Brazil, severely affected this river. In this study, we showed the trace metals concentrations in the water and margin sediments of the DRB during the dry and wet seasons. This new data was obtained in 2011, prior to the environmental disaster caused by disruption of the dams. We observed Cr, Ni and Pb contaminations in the sediments. The concentrations of these elements in the high river flow (wet season) were higher than the guideline values (GV) of level II and geoacumulation Index (Igeo). However, Fe and Mn concentrations were well above the GV in the wet season. The levels of these two elements were lower than the values found in the region's Haplic Cambisol. Furthermore, the comparison between our data and those of the technical reports released after the dams rupture shows that iron ore mine tailings greatly alter the trace metals concentration in water and sediments. However, we have observed a trend of resilience that requires more systematic and careful studies in DRB.

Effects of Urbanization on Water Quality and the Macrobenthos Community Structure in the Fenhe River, Shanxi Province, China

The relationships between land use types, water and sediment parameters, and macrobenthos community structures in the upper and middle reaches of the Fenhe River and urbanization intensity were studied. Samples were collected from 23 sampling sites. Spearman rank correlation analyses were performed to assess the relationships between the percentages of impervious area or the proportions of four land uses and the water and sediment physicochemical properties, heavy metal and polycyclic aromatic hydrocarbon concentrations in water and sediment, and biological indicators of the macrobenthos communities. Some water parameters (temperature, oxidation-reduction potential, electrical conductivity, total N concentration, total P concentration, ammonia-N concentration, and nitrate-N concentration), some sediment parameters (total N concentration, total P concentration, organic matter content, percentage of particles with diameters <2 mm, and polycyclic aromatic hydrocarbon, Cd, Cr, Cu, Ni Pb, and Zn concentrations), and some macrobenthos parameters (Berger–Parker index and percentages of collectors, tolerant taxa, and Oligochaeta) significantly positively correlated with the percentage of impervious area. Some water parameters (pH and dissolved oxygen concentration), some sediment parameters (percentage of particles with diameters >2 mm), and some macrobenthos parameters (total biomass, total number of taxa, Shannon’s index, N diversity index, and percentages of Ephemeroptera, Plecoptera, Trichoptera, filterers, scrapers, and sensitive taxa) significantly negatively correlated with the percentage of impervious area. The results indicate that intensification of urbanization has strongly affected the water, sediment, and macrobenthos in the Fenhe River watershed.

Endonezya Kayalı Körfezi’nde Bulunan Stichopus herrmanni’nin (Semper, 1868) (Holothuroidea; Stichopodidae) Dokuları İle Su Ve Zeminde Hg, Au, Fe Ağır Metalleri Birikimi

Heavy metals concentrated in waters can also accumulate in sediments and various biota. This research was conducted to examine the concentration of heavy metals in seawater, sediment, intestine and meat of golden sea cucumber Stichopus herrmanni in Kayeli bay, Buru Island, Indonesia. The concentrations of heavy metals Hg, Au, and Fe were analyzed using the AAS, and the tissue damage of S. herrmanni used the HE staining method. Correlation analysis and multiple linear regression were used to examine the correlation and the effect of the independent variables (heavy metals Hg, Au, and Fe) partially on the dependent variable (damage on intestinal villi of S. herrmanni) with a statistically significant at α= 0.05. The results showed that the highest to lowest heavy metal concentrations in water was Hg>Fe>Au, while the concentration of heavy metals in water, intestine and meat was of sea cucumber was Fe>Hg>Au. There was a correlation between heavy metals in sediments, intestines, and meat which caused damage to intestinal villi, while the multiple linear regression tests showed a probability of 0.012<0.05 for Fe, a probability of 0.000< for Hg, while probability >0.05 for Au on the damage of intestinal villi of S. herrmanni. This shows that Fe has a significant potential to cause damage to the intestinal villi of S. herrmanni. Fe is highly concentrated in sediments, intestines and meat showed a positive correlation to the damage of intestinal villi of S. herrmanni.

Concentrations, Possible Sources and Health Risk of Heavy Metals in Multi-Media Environment of the Songhua River, China

Heavy metal pollution in the river environment has been a source of widespread interest due to potential threats to human health and ecosystem security. Many studies have looked at heavy metal pollution in the context of single source-pathway-receptor relationships, however few have sought to understand pollution from a more wholistic multi-media perspective. To investigate potential risks in a more wholistic way, concentrations of six heavy metals (Cd, Cr, Ni, Cu, Zn and Pb) were detected in multi-media (water, sediment and riparian soil) collected from 14 sampling sites in the main stream of the Songhua River. Chemical analyses indicated that the average concentration of heavy metals in water followed: Zn > Cr > Cu > Pb > Ni > Cd, with a different trend observed in sediments and riparian soil: Zn > Cr > Ni > Pb > Cu > Cd. The potential risk was evaluated using the heavy metal pollution index (HPI), Nemerow pollution index (PN), hazard index (HI) and carcinogenic risk (CR) metrics. Results showed that all HPI values were lower than the critical level of 100 indicating that the levels of these targeted heavy metals were within drinking water safety limits. The PN indicated that both sediment (2.64) and soil (2.95) could be considered “moderately polluted”, with Cd and Zn providing the most significant contributions. A human health risk assessment suggested that the non-carcinogenic risks were within acceptable levels (HI < 1), as was the cancer risk associated with dermal adsorption (CR <10−6). However, the CR associated with ingestion exposure (4.58 × 10−6) exceeded the cancer risk threshold (10−6) indicative of elevated cancer incidence in exposed populations. Health-risk estimates were primarily associated with Cd in the Songhua River. Source apportionment was informed by Pearson correlation analysis coupled with principal component analysis (PCA) which indicated that Cu was mainly derived from natural (geogenic) sources; Cr and Ni were associated with industrial emissions; Pb might be derived from agricultural and transportation sources; Zn might be from industrial, agricultural activities and transportation; while Cd is likely from industrial and agricultural emissions. The source apportionment information could provide the basis for a risk-management strategy focused on reducing Cd and Zn emissions to the riverine environment. Results from this study will provide the scientific knowledge that is needed for measuring and controlling heavy metals sources and pollution characteristics, and identifying the potential cancer risk with different exposure pathways, as well as making effective environmental management policies at catchment or regional scales.

Seasonal variations of trace metals from water and sediment samples in the northern Bay of Bengal.

We aimed to determine the temporal variation of trace metals concentrations in surface water and surface sediment samples at Kutubdia Channel, Bangladesh. Trace metals of samples were detected using energy dispersive X-ray fluorescence (Energy-dispersive X-ray spectroscopy) method. The lowest concentration of metals was found in water samples during post-monsoon season and the highest during pre-monsoon season (Cu: 0.030±0.001μg/L in pre-monsoon and 0.026±0.002μg/L in post-monsoon, Zn: 0.087±0.003μg/L in pre-monsoon and 0.073±0.002μg/L in post-monsoon, Fe: 0.080±0.001μg/L in pre-monsoon and 0.055±0.001μg/L in post-monsoon). In contrast, metal concentration in surface sediment samples were higher in post-monsoon than in pre-monsoon season i.e. Cr 11mg/kg in pre-monsoon and 12mg/kg in post-monsoon, Mn 571mg/kg in pre-monsoon and 606mg/kg in post-monsoon, As (8mg/kg in pre-monsoon and 10mg/kg in post-monsoon, Pb (22mg/kg in pre-monsoon and 24mg/kg in post-monsoon, and Fe 2317mg/kg in pre-monsoon and 2435mg/kg in post-monsoon. We found a spatial gradient of high to medium to low in trace metal concentration from river to river mouth to offshore area. Considering the sources of metals, land erosion by waves and tidal action, an influx of water and sediment from the surrounding rivers, agricultural waste, industrial effluent and sewage are the most likely sources of metal pollution in the study area. We conclude that proper management strategies should be adopted to control the pollution and conserve the ecosystem health.

Biochemical and histopathological alterations of Oreochromis niloticus fish related to heavy metals in Lake Nasser, Egypt

Introduction: Lake Nasser is the one of the longest man-made lakes in the world. The surface area and water level of the lake are depending mainly on the annual flow of flood water comes from the Blue Nile from the Ethiopian highlands, it is a major source used for drinking irrigation, fisheries and other domestic purposes.Material and methods: Fish samples were collected from five stations in lake Nasser including Khor Forgond, Khor Toushka west, Khor Ahmer, Garf Hussen and Khor Ebreem during summer 2019. The determination of blood serum glucose, total protein, albumin, total lipids, creatinine, urea, uric acid AST and ALT were carried. Also, the accumulation of iron, manganese, copper, zinc and cadmium in liver, gills and muscle organs of collected Oreochromis niloticus fish from the above stations were determined. In addition to, the same studied organs were histopathologically examined.Aim of the work: This study aim to investigate the impact of the environmental pollution of Lake Nasser on histology of liver, gills and muscles and biochemical parameters of a commercially important O. niloticus fish and that living in this lake NasserResults and Discussion: The results of the present study exhibited increased levels of glucose, lipid, AST, ALT, urea, uric acid and creatinine, while decreased total protein in blood serum of O. niloticus fish samples at Garf Hussen site. Heavy metals accumulations in O. niloticus fish organs at area under investigation were in following descending order: iron> zinc> manganese> cadmium> copper. While, heavy metals accumulations according to organs were in following descending order: liver > gills>muscle. It was found that the metals accumulation in non-edible organ (liver) more than that in edible organ (muscles), the concentration of heavy metals in the studied fish tissues is dependent upon the type organ as well as the type of metal and concentration of heavy metals in water. The accumulation of these heavy metals in the studied fish organs, give rise to histopathological alteration. These alterations including, hemorraghe, hemosidrin, edema, degeneration, necrosis and hyperplasiae, separation in secondary lamellae. We can concluded that fish samples collected from Garf Hussen were more effected than those obtained from other stations.Conclusion: Oreochromis niloticus samples collected from Garf Hussen were more affected by heavy metals those obtained from other stations. But this impact was still within permissible limit. O. niloticus in lake Nasser is valid for human consumption without any negative effect

Groundwater vulnerability and trace element dispersion in the Quaternary aquifers along middle Upper Egypt.

Association of trace metal concentrations in water is problematic; however, its information is scarce and sometimes contradicted. This work presents variations in dissolved major constituents and trace element concentrations along the quaternary aquifers located in middle Upper Egypt (Minia and Assiut governorates). A total of 205 groundwater samples from these aquifers were collected. Auxiliary parameters (pH, alkalinity, and conductivity), major cations (Ca2+, Mg2+, Na+, and K+), dominant anions (HCO3-, SO42-, Cl-, and NO3-), and trace element (B, Fe, Cu, Mn, Ni, Pb, Cd, and Cr) concentrations were measured in all samples. Univariate (correlation coefficient and scatter matrix) analysis was employed combined with multivariate (principal coordinates analysis) analysis to identify the chemical characteristics of groundwater that are responsible for generating most of the variability within the dataset. Also, hierarchical cluster analysis was applied to classify the geochemical origin of the groundwater constituents. The results indicate that the groundwater pollution is mainly due to water-rock interactions, including aquifer matrix dissolution, redox reaction of trace metals, input from wastewater, and agricultural fertilizers.

DETERMINATION OF HEAVY METAL CONTENTS IN WATER OF LLAPI RIVER (KOSOVO). A CASE STADY OF CORRELATIONS COEFFICIENTS

Atomic absorption spectroscopy has been used to analyses and assesses the heavy metal content in water of the Llapi river, Kosovo. In this study, the assessment of heavy metals in water was realized in the summer period. Statistical studies have been carried out by calculating basic statistical parameters, anomalies (extremes and outliers) and correlation coefficients between different pairs of variables. The concentration of Cr, Ni, Zn, Cu and Fe in all sample stations were found to be under WHO recommended norms. But the concentration of Cd and Pb in all sample stations and concentrations of Mn at several stations were found to be above WHO recommended norms originated from mineral sources (ores) in this area. The statistical regression analysis has been found a highly significant positive relationship of Cd with Ni, Mn, Fe and Pb originated mainly of sulphide ores in this area.

Chronic exposure to heavy metals from informal e-waste recycling plants and children's attention, executive function and academic performance

E-waste contains valuable metals that require appropriate waste management plans. However, rudimentary e-waste processing methods are a source of heavy metals environmental pollution. This study has characterised concentrations of heavy metals in soil (n = 10), water (n = 10) and hair (n = 44) of children in areas surrounding Jakarta (Indonesia), where e-waste is being or has been conducted in the past, and in a reference unexposed site. Chronic exposure to Mn, Pb, Hg, As and Cd and its associations with attention and executive function, characterised with the Trail Making Test (TMT), along with academic performance scores was conducted using multivariate regression analysis. Models were adjusted for age, gender, parental education, environmental tobacco smoke and residential traffic. Lead (3653 ± 3355 mg/kg), cadmium (3.4 ± 0.9 mg/kg) and mercury (15.2 ± 28.5 mg/kg) concentrations from soil and manganese concentrations in water (1.43 ± 0.64 mg/L) in the exposed sites were higher than current regulations. Heavy metal concentrations in hair of children living near e-waste facilities was higher than for children living in non-exposed areas (Pb: 0.155 ± 0.187 vs 0.0729 ± 0.08 mg/g; Mn: 0.130 ± 0.212 vs 0.018 ± 0.045 mg/g; Hg: 0.008 ± 0.0042 vs 0.002 ± 0.0011 mg/g) suggesting chronic exposure to heavy metals. Manganese exposure was associated with worse cognitive performance in the domains of attention (TMT-A score: 66 s, 95% CI 0.09, 132), executive function (TMT-B score: 105 s, 95% CI 11.5, 198) and social sciences (−29%, 95% CI −54, −4.7) (per unit of Mn in hair mg/g). These results suggest that informal e-waste activities contribute to local heavy metal soil contamination, and could be an important source of metal exposure to children living in the vicinity of these facilities with putative impacts on their cognitive performance. E-waste management regulation and remediation programmes should be implemented to reduce environmental pollution and associated health effects.

Radiological health risk assessment of drinking water and soil dust from Gauteng and North West Provinces, in South Africa

Long-lived natural radionuclides such as (238U) uranium-238, (232Th) thorium-232, (226Ra) radium-226 and (40K) potassium-40 and heavy metals are normally exposed to the surface during mining activities. They enter the human body when inhaled (as dust) or ingested (by drinking contaminated water). An intake of large concentrations of these radionuclides and heavy metals can lead to health effects such as development of cancers. The aim of this work was to assess the radiological health risk due to intake of radionuclides in dust and drinking water from the West Rand gold mining area and Modiri Molema Municipality (MMM) water treatment plant. The dust samples were analyzed for radionuclides of interest using the well-type high purity Germanium detector. Water samples were collected before and after purification from the Modiri Molema Municipality water treatment plant and analyzed using the ultra-low level Liquid Scintillation Counter (LSC), to evaluate the gross alpha and beta radioactivity dose levels of the radionuclides in water. An Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to evaluate the heavy metal concentrations in the drinking water after purification at the treatment plant. The total inhalation effective dose obtained in this study was (2.71 × 10−1 and 1.31 × 10−1) μSv.y−1 for adults and infants respectively, which is below the prescribed dose range of 5–10 μSv.y−1. The mean activity concentrations of the radionuclides in air dust were found to be; 226Ra, (2.14 ± 0.82) × 10−6 (Bq.m−3), 238U (6.08 ± 2.17) × 10−7 (Bq.m−3) and 232Th (2.65 ± 1.1) × 10−7 (Bq.m−3). The activity concentration of 226Ra obtained exceeded the world average by 2 times. The Raeq, the external hazard (Hex) and internal hazard (Hin) indices were calculated and the values obtained from soil were lower than the world average. However, the absorbed dose rate in air was higher than the world averages of 60 nGyh-1. The minimum and maximum gross alpha activity obtained was 0.0041 (Bq.L−1) and 0.0053 (Bq.L−1) respectively, while the minimum and maximum gross beta activity obtained for water samples was 0.0083 (Bq.L−1) and 0.0105 (Bq.L−1) respectively. More heavy metals were detected in the first two stages of the water treatment than on the last two stages, nevertheless, their concentrations did not exceed recommended limits. The results for soil dust indicates that the windward areas might pose health risks for human population staying in the area and the activity concentration for drinking water indicate that the specific activity in the water supply after purification is below the WHO guideline limit of 0.5 (Bq.L−1) for gross alpha and 1 (Bq.L−1) for gross beta. The results obtained were also within the range of the South Africa Department of Water Affairs and Forestry target water quality limit of (0–1.38) (Bq.L−1) for gross beta activity. Heavy metals concentrations in drinking water did not exceed the stipulated limits by USEPA and DWAF. Therefore, this water after treatment is radiologically and toxicologically safe for the members of the public.

Evaluation of groundwater quality for drinking purposes: a case study from the Beheshtabad Basin, Chaharmahal and Bakhtiari Province, Iran

Groundwater quality monitoring is of great importance in Iran’s arid and semi-arid regions where water scarcity exists. This study assessed background information on groundwater quality and heavy metals concentration in the spring water of the Beheshtabad Basin, located in Chaharmahal and Bakhtiari Province, Iran, to examine the suitability of the groundwater for drinking. Groundwater samples were collected from five springs in the basin during the time frame of February 2014 and September 2015 and analyzed in terms of physicochemical characteristics such as pH, electrical conductivity (EC), total dissolved solids (TDS), cations, anions, and heavy metal concentration. These parameters were used to determine the groundwater’s suitability for domestic purposes by comparing their measured values to the maximum permissible limits according to recommendations of the World Health Organization. The results revealed that most groundwater samples are suitable for drinking. During the rainy season, however, spring waters are bacteriologically contaminated and unsuitable for human consumption. As important parameters for determining drinking water quality, water quality index (WQI) values in the present study indicated very poor quality water for some groundwater samples in the area dominated by weathering of rocks and dissolution of salts from the bedrock into the water resources, which can be a serious threat to the ecological habitat.

Assessment of heavy metals in water, sediment and shellfish organisms in typical areas of the Yangtze River Estuary, China

Identifying the transformations of heavy metal in different media is a scientific issue, and geographical detector is applied to evaluate the spatiotemporal stratified heterogeneity mechanisms for heavy metals in the Yangtze River Estuary. Heavy metal concentrations in water and sediment were consistent with lognormal distributions. Their concentrations were organized into four classes. Class 1 included concentrations that were less than or equal to 25%, Class 2 included those between 25%–50%, Class 3 concentrations were between 50%–75% and Class 4 were >75%, which were based on their lognormal distributions. In water and sediment, the mean heavy metal concentrations yearly decreased from 2012 to 2016. The Chongming area was significantly lower than those found in the other areas, which is the least affected area by anthropogenic activities. The explanatory power of sediment to spatiotemporal stratified heterogeneity of heavy metals in shellfish organisms was much greater than that of water.

Sewage Effluent Causes Metal Pollution of a Sub-tropical River System in Zimbabwe.

Metal pollutants are persistent in the environment and of concern to human health. The aim of the study was to assess the distribution of metals (Cr, Fe, Pb, Mg and Cu) in Sebakwe River. Water and sediment samples were collected from upstream reference sites (4 and 5) and influenced downstream sites (1, 2 and 3) of the sewage effluent discharge point. Pb concentrations in water were significantly higher (p < 0.05) in sites 1 and 2 downstream of the sewage discharge point. In the sediments, the sites downstream of the effluent discharge point had significantly higher concentrations of Cu (p < 0.05) and Cr (p < 0.05). A comparison of metal concentration in water with World Health Organization and Standards Association of Zimbabwe standards revealed that the levels of Pb in water were above the recommended limits, posing a health risk to Pb poisoning for people living along Sebakwe River.