Heavy Metals Pb Research Articles

Heavy metals concentration in sediment and their bioaccumulation in several organisms in Benoa Bay and Lembongan Island, Bali, Indonesia

Abstract. Putri PYA, Rastina, Prartono T, Ismet MS. 2024. Heavy metals concentration in sediment and their bioaccumulation in several organisms in Benoa Bay and Lembongan Island, Bali, Indonesia. Biodiversitas 25: 3230-3238. Human activities could be responsible for introducing heavy metals into coastal areas, and it can contaminate coastal waters such as the tourism area of Benoa Bay and coastal ecosystems of Lembongan Island, Bali, Indonesia. This study aimed to assess the extent of heavy metals on the sediment of those area and their accumulation rate in several marine organisms, including macro-algae (Ulva sp.), seagrass (Thalassia hemprichii), and sea urchin (Diadema sp.). Samples of surface sediments and marine organisms were collected at six stations for both areas and the presence of five heavy metals (Fe, Pb, Cd, Cu, and Cr) was determined using the AAS method. The concentration those metals varied significantly across the six stations. The geo-accumulation index showed that the sediment has been contaminated by Pb and Cd. The ecological risk of heavy metals contamination in Benoa Bay was apparently higher compared to that in Lembongan Island. Marine organisms in Benoa Bay also significantly accumulated heavy metals than those observed in Lembongan Island. Bioconcentration factor (BCF) shows that Cd, Cr, and Pb were the most accumulated heavy metals in marine organisms (BCF>1). It, therefore, suggest that future studies of the bioavailability of heavy metals and exploration the varying capacities of marine organisms are required. Such important information can be used to predict the accumulation of heavy metals in human bodies, and the possibly daily consumption of marine organisms caught from Benoa Bay and Lembongan Island waters.

Distributions of Some Heavy Metals in Agricultural Soil and Their Environmental Impacts in Chamchamal District, Sulaymaniya Governorate, Northeastern Iraq

Soil samples were collected from Sangaw, Qadir Karam, and Takiat Gabbary sites of Chamchamal agricultural soil Sulaymaniya Governorate, Northeastern Iraq. The heavy metals Co, Cr, Cu, Ni, Cd, Zn, Pb, As, and Mn. in Eighteen soil samples were studied and used as an indicator for pollution by using many indices such as the contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo), pollution load index (PLI), pollution ecological risk (Er), and risk index (RI). The results showed that the heavy metal concentration values were as follows: Mn> Ni> Zn> Cr> Cu> Pb> Co> As> Cd. The CF data showed that the soil in the study area has low contamination with Co, Cr, Cu, and Mn and moderate contamination with Ni, Pb, Zn, and As. Also, the soil samples are considerably contaminated by Cd and As in the Qadir Karam site. According to the results of Igeo, the soil was unpolluted for Co, Cr, Ni, Cu, Pb, Zn, and Mn, while being unpolluted to moderately polluted for Cd and As. The EF calculation results indicated that Co, Cr, Cu, and Mn have deficient to minimal enrichment, and have moderate enrichment for Ni, Pb, and Zn, while, for Cd and As is significant enrichment. According to the Er values, all the heavy metals in the studied sites reflect a low potential ecological risk. The risk index (RI) value is classified as moderate ecological risk for heavy metals in all sampling sites.

Prediction of soil heavy metal contents in urban residential areas and the strength of deep learning: A case study of Beijing

Predicting soil heavy metal (SHM) content is crucial for understanding SHM pollution levels in urban residential areas and guide efforts to reduce pollution. However, current research indicates low SHM prediction accuracy in urban areas. Therefore, we employed a deep learning method (fully connected deep neural network) alongside four other methods (muti-layer perceptron, radial basis function neural network, multiple stepwise linear regression, and Kriging interpolation) to predict SHM content in the urban residential areas of Beijing and demonstrated the strength of deep learning in improving prediction accuracy. We found the contents of the evaluated heavy metals (Cd, Cu, Pb, and Zn) exhibited significant correlations with numerous other soil physicochemical properties and environmental factors. The prediction accuracy for Cu, Pb, and Zn contents was relatively high across different methods. Notably, deep learning showed considerable strength in predicting the contents of the four heavy metals, with the R2 for the test set of the model ranging from 0.75 to 0.91. Compared to other methods, deep learning achieved markedly higher prediction accuracy according to different accuracy evaluation indicators (e.g., deep learning showed increases in the cumulative R2 of the four heavy metals ranging from 53.16 % to 187.36 % compared to other methods). Our study indicates that deep learning can significantly improve SHM content prediction accuracy in urban areas and is highly applicable in urban residential areas with complex environmental influences.

Comparison and mechanism analysis of MgO, CaO, and Portland cement for immobilization of heavy metals in MSWI fly ash

The significant production of municipal solid waste incineration fly ash (MSWI FA) underscores the importance of developing efficient solidification materials. This study employed MgO and CaO for immobilizing MSWI FA (with a 70% fly ash incorporation), and the immobilization effect was compared with that of Portland cement (PC). Experimental findings revealed that MgO exhibited the most effective stabilization for heavy metals (Cd, Cu, Pb, and Zn) compared to CaO and PC. XRD, FTIR, TG, and SEM analysis indicated that the principal hydration products in MSWI FA binders solidified with MgO, CaO, and PC were Mg(OH)2, CaCO3, and C-S-H gel, respectively. Mg(OH)2 efficiently immobilized heavy metals through chemical complexation and surface adsorption mechanisms. The MgO-treated MSWI FA demonstrated the highest residual fractions and the lowest easily leachable fractions. Moreover, the leaching characteristics of heavy metals were significantly influenced by the pH level, so MgO-treated MSWI FA with a leachate pH of 9.18 achieved the precipitation and stabilization of most heavy metals. In summary, this study provided an effective material selection for MSWI FA immobilization and presented a novel strategy for MSWI FA management.

Glacier mice as a temporary sink for fallout radionuclides and heavy metals on the Norwegian glacier Austerdalsbreen

Glacier mice are peculiar rolling or stationary moss balls found on the surface of some glaciers. They may harbour an ecological habitat for cold-adapted invertebrates and microorganisms, but little is known about their potential to accumulate and disseminate harmful elements and substances. In this study, we investigate the presence of fallout radionuclides (137Cs, 238Pu, 239Pu, 240Pu, 210Pb) and heavy metals (Pb, As, Hg, Cd) in glacier mice and compare the results to bryophytes from adjacent glacier ecosystems. Samples were collected at Austerdalsbreen, a Norwegian outlet glacier from Jostedalsbreen ice cap.Maximum activity concentrations for bryophytes are 552 ± 12 Bq kg−1 for 137Cs, 3485 ± 138 Bq kg−1 for 210Pb, 0.0223 ± 0.065 Bq kg−1 for 238Pu and 4.34 ± 0.43 Bq kg−1 for 239+240Pu while maximum heavy metals concentrations are 70.5 mg kg−1 for Pb, 1.0 mg kg−1 for As, 1.6 mg kg−1 for Hg and 0.13 mg kg−1 for Cd. Maximum activity concentrations in cryconite are 1973.4 ± 5.0 Bq kg−1 for 137Cs, 3632 ± 593 Bq kg−1 for 210Pb, 0.51 ± 0.11 Bq kg−1 for 238Pu and 13.1 ± 1.4 Bq kg−1 for 239+240Pu and maximum heavy metal concentrations are 50.4 mg kg−1 for Pb, 3.4 mg kg−1 for As, 1.5 mg kg−1 for Hg and 0.082 mg kg−1 for Cd. We find that glacier mice show lower activity concentrations of radionuclides compared to cryoconite. The major source of plutonium isotopes is related to global fallout, whereas detected radio-cesium may be additionally affected by post-Chernobyl fallout to an unknown extent. Comparison between glacier surface and adjacent glacial habitats shows higher concentrations of heavy metals in glacier mice on the glacier ice surface and medial moraines compared to bryophytes in the glacier forefield. Glacier mice exported from a receding glacier may affect the cycling of radioactive and metal pollutants in developing proglacial ecosystems.

Strongly acidic lead contaminated soil solidification/stabilization using metakaolin-modified fly ash phosphoric-based geopolymer

The existing binders are difficult to be compatible with the acidic environment of acidic heavy metal contaminated soil, it is hard to repair acidic heavy metal contaminated soil. In this study, a modified acid phosphorus-based geopolymer (MAPG) binder suitable for the solidification/stabilization (S/S) treatment of acidic heavy metal Pb2+ contaminated soil was fabricated using aluminum dihydrogen phosphate (ADP) as activator, fly ash and metakaolin (MK) as raw materials. The influences of liquid–solid ratio (L/S), MK content, ADP concentration, curing age and leaching environment on the compressive strength, toxic leaching, resistivity, pH and EC of MAPG stabilized acidic Pb2+ contaminated soil were studied. Meantime, the X-ray diffraction, scanning electron microscopy, fourier transform infrared spectroscopy, and mercury intrusion (MIP) experiments were used to study the chemical properties and microscopic performance of MAPG treated acidic Pb2+ contaminated soil. The results showed that the MAPG binder prepared from MK had an excellent S/S effect on the acidic Pb2+ contaminated soil, and the MAPG binders had good compatibility with the acidic environment. The compressive strength of each group of MAPG stabilized soil could meet the strength standard (>350 kPa) for solid waste landfill and Pb2+ leaching concentration is < 5 mg/L for toxicity identification criteria after 7 days of curing. With an increase in curing age, the strength of stabilized acidic contaminated soil decreased slightly, but the strength still met the requirements of landfill strength standard after 28 days of curing. In three different leaching environments, the Pb2+ leaching decreased with an increase in curing age. Microscopic analysis showed that the main crystalline compounds in stabilized contaminated soil were potassium feldspar, Berlinite and lead phosphate compounds, and their contents were related to L/S, MK content, ADP concentration, and curing time. Potassium feldspar, berlinite, and lead phosphate compounds could not only fill pores, but also had physisorption, encapsulation and chemical precipitation effects on Pb2+. The study could provide an economical, environmental friendly and efficient binder for the remediation of acidic Pb2+ contaminated soil, but the further investigation into the long-term effectiveness of the MAPG binder or its applicability to other types of contaminated soil is also needed.

Evaluation of Water Quality Indexes and Heavy Metal Pollution Indexes of Different Industrial Effluents and Karnaphuli River Water in Chattogram, Bangladesh

ABSTRACTThe study evaluated the water quality index (WQI) and heavy metal pollution index (HPI) of different industrial effluent and surface water from various sites of the Karnaphuli River, based on the weighted arithmetic index method. The samples were collected from 20 different industries, including textile dyeing, textile washing, oil processing, chemicals, and tannery, and 17 stations of the Karnaphuli River, from the Kalurghat Bridge to the estuary where the river meets with the Bay of Bengal. This study was carried out in the dry season of the 2021–2022 fiscal year. Six physicochemical parameters, namely pH, biochemical oxygen demand, chemical oxygen demand, total dissolved solids, electrical conductivity, and hardness, were taken for the determination of the WQI, and concentration of heavy metals (Pb, Fe, Cd, Cu, Cr, Mn, and Ni) were considered for the calculation of the HPI. Both indexes were calculated against the Bangladesh Standard (denoted by subscript a) and WHO standards (denoted by subscript b). The water quality indexes WQIa and WQIb for industrial effluent ranged from 11.66 to 176.77 and 44.45 to 9703.99, respectively. Samples namely TD‐5, TD‐7, TD‐8, TD‐9, TD‐10, OS‐1, and C‐1 showed excessively high WQI value. On the other hand, the HPIa and HPIb of industrial effluent varied from 43.6 to 167,785.3 and 0.34 to 18,412.3, respectively. Furthermore, oil processing and chemical effluents showed noticeably higher HPI values than other industrial samples. Both WQI and HPI values indicated a serious pollution load in most experimental samples. No river water sample showed a WQI value below 100, denoting it was unfit for consumption. The water quality indexes WQIa and WQIb for river water samples ranged from 1275.40 to 29,405.77 and 131.20 to 5860.99, respectively. According to the Bangladesh Standard, the river water samples were moderately to highly polluted by metal. The highest HPI value for the river water sample was 7965, denoting extreme metal pollution. The investigation revealed that most industrial effluents and Karnaphuli River water samples contained significant pollution load. Therefore, effective measures must be adopted immediately for future sustainability to cope with this contamination. The results emphasize the immediate requirement for strict regulations and advanced water treatment technologies to reduce contamination risks in the Karnaphuli River. Prompt action by authorities is essential to safeguard the river, prevent ongoing ecological damage, and address metal accumulation in fish affecting the food chain. Public awareness and legislative measures are vital for ecosystem preservation.

Efficient removal of lead from polluted paddy soil by one-pot synthesized Nano-Fe3O4 incorporated stable lignin hydrogel

Lead (Pb) contamination in agricultural soils poses a significant threat to both ecosystems and human health. While nano-Fe3O4 exhibits promising potential for Pb remediation, its practical application in the soil is hindered by its’ biotoxicity, easy aggregation, and the risk of secondary pollution. Thus, this study presents a novel approach wherein Fe3O4 was incorporated into hydrogel via a one-pot synthetic strategy (Fe3O4@LH). This incorporation enhanced the mechanical properties and environmental stability of the hydrogel composites. Based on the mechanical properties, environmental stability, and single-point adsorption results for Pb, we selected Fe3O4@LH-4 for further research. The removal mechanism and the feasibility of employing Fe3O4@LH-4 for Pb removal from paddy soil were investigated through batch adsorption experiments and soil culture studies. Results showed that the adsorption process was primarily governed by swelling adsorption, electrostatic adsorption, ion exchange, precipitation, nanometer effect, and complexation mechanisms. The application of Fe3O4@LH-4 significantly led to the reduction of 16.7 %–25.4 % in soil Pb content, with removal rates escalating alongside increased dosage and application periods of Fe3O4@LH-4. Fitting results of the prediction model indicated that the Pb content in mildly Pb-contaminated soil (186.55 mg/kg) would decrease to be below the risk control standard for soil contamination of agricultural land in China (140 mg/kg) after 112 days of continuous application. Concurrently, cadmium and arsenic contents in the soil decreased by 5.2 %–10.8 % and 7.1 %–16.7 %, respectively. Moreover, the application of Fe3O4@LH-4 positively influenced soil nutrient levels, with total nitrogen and soil organic matter content significant increments of 13.6 %–41.0 % and 4.6 %–16.1 %, respectively. Furthermore, Fe3O4@LH-4 recovery exceeded 88.3 % after a 90-day application period. These findings underscore the potential of Fe3O4 incorporated hydrogel as a promising agent for the sustained removal of heavy metal Pb from paddy soil.

Contamination Characteristics and Source Apportionment of Heavy Metal in the Topsoil of a Small Watershed in South Taihang

With the rapid development of industrialization and urbanization, the issue of soil environmental pollution is becoming more and more prominent, especially concerning heavy metal contamination, which has garnered significant scholarly attention. The surface watershed formed by waterline is influenced by various factors such as topography, industrial emissions, and agricultural runoff, resulting in a complex process of migration and accumulation of heavy metal elements from multiple sources. In this study, the pollution characteristics and sources of heavy metal elements Hg, As, Pb, Ni, Cd, Cr, Cu and Zn in 165 surface soil samples from the Manghe River watershed in Jiyuan City were comprehensively analyzed using a variety of methods, including statistics, geostatistics, enriched factor analysis and the Positive Matrix Factorization Model (PMF). The results showed that the concentrations of Hg, Cd, As, Cu, Pb and Zn exceeded their corresponding background values with varying degrees of enrichment. Notably, the average contents of Cd, Hg and Pb were 26.70 times, 3.69 times and 4.49 times higher than those in Chinese soils on average, respectively, showing obvious enrichment characteristics. Moreover, there were distinct spatial distribution patterns for each heavy metal element; Ni and Cr exhibited similar trends mainly controlled by the parent material, while human activities significantly affect the other six elements forming high-value areas around mining and related industries. It is noteworthy that Cu, Hg and Zn were influenced by dominant wind direction in autumn and winter, forming sub-high-value zones in southern forested areas; meanwhile, Cu and Zn were also influenced by agricultural fertilizer application as well as surface runoff, leading to secondary high-value areas in the dryland areas. Further analysis revealed a significant positive correlation among these heavy metal elements, suggesting that they may share common sources. Through the PMF Model, four main factors were identified, with factor 2 (36.25%), factor 1 (23.00%), factor 3 (21.20%) and factor 4 (19.55%) ranked in descending order of contribution rate. The heavy metal pollution in the study area was attributed to anthropogenic activities and natural factors, accounting for 63.75% and 36.25%, respectively. Coal mining, chemical industry smelting, vehicle emissions and excessive use of agrochemicals were identified as the main sources of heavy metal pollution. These pollutants entered the soil through direct emissions, atmospheric deposition, transportation and agricultural activities, exerting a significant impact on the soil environment. Therefore, delving into the spatial distribution pattern of soil heavy metal pollution and precise analysis of its sources are of great importance for effective treatment and remediation of soil heavy metal pollution in small watersheds, maintaining healthy soil ecology and safeguarding human health.

Mineral and Organic Materials as Factors Reducing the Effect of Petrol on Heavy Metal Content in Soil.

As industrial production increases worldwide, so does the demand for fuels. The transport of fuels from the point of production to the end user poses a risk of environmental pollution, both during transport and during combustion in internal combustion engines. The soil is a part of the environment which is particularly sensitive to contamination by petroleum substances. For this reason, research has been carried out into the possibility of reducing the impact of petrol on the content of heavy metals in the soil using various materials, both mineral (bentonite, calcium oxide) and organic (compost). These played an important role in the in situ remediation of contaminated soils. Petrol contamination increased the content of some heavy metals (Pb, Cd, or Ni), while it decreased the content of other metals (Cr, Zn, Co, and Cu) in the soil. The materials used in this study significantly altered the levels of heavy metals in the soil. The strength of the effect varied and the direction of the effect depended on the element. Bentonite was the most effective, while calcium oxide and especially compost were less effective. The most beneficial (limiting) effect of calcium oxide was shown on the soil content of cadmium, cobalt, and chromium, while the bentonite effects were on the content of chromium. The application of the abovementioned materials seems to be effective in reducing low level soil contamination by petrol.

Machine learning approaches to identify spatial factors and their influential distances for heavy metal contamination in downstream sediment

Contaminated sediments can adversely affect aquatic ecosystems, making the identification and management of pollutant sources extremely important. In this study, we proposed machine learning approaches to reveal sources and their influential distances for heavy metal contamination of downstream sediment. We employed classification models with artificial neural networks (ANN) and random forest (RF), respectively, to predict the heavy metal contamination of stream sediments using upland environmental variables as input features. A comprehensive Korean nationwide monitoring database containing 1546 datasets was used to train and test the models. These datasets encompass the concentrations of eight heavy metals (Ar, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in sediment samples collected from 160 stream sites across the nation from 2014 to 2018. Model's prediction accuracy was evaluated for input feature sets from different influential upland areas defined by different buffer radii and the watershed boundary for each site. Although both ANN and RF models were unsatisfactory in predicting heavy metal quartile classes, RF-classifiers with adaptive synthetic oversampling (ORFC) showed reasonably well-predicted classes of the sediment samples based on the Canada's Sediment Quality Guidelines (accuracy ranged from 0.67 to 0.94). The best influential distance (i.e., buffer radius) was determined for each heavy metal based on the accuracy of ORFC. The results indicated that Cd, Cu and Pb had shorter influential distances (1.5–2.0 km) than the other heavy metals with little difference in accuracy for different influential distances. Feature importance calculation revealed that upland soil contamination was the primary factor for Hg and Ni, while residential areas and roads were significant features associated with Pb and Zn contamination. This approach offers information on major contamination sources and their influential areas to be prioritized for managing contaminated stream sediments.

Altered 16S rRNA gene size in Agrobacterium tumefaciens at IC50 of heavy metals

Agrobacterium tumefaciens is a soil-endemic bacterial species that causes crown galls disease on a range of medicinal and economically important plants. In this study, the diagnosis of this bacterium was confirmed by its formation of crown galls on the discs of carot. And when treated in a laboratory with eight different heavy metals (Mo, Fe, Zn, Cu, Cr, Cd, Ni, and Pb), and with ten concentrations (40, 20, 10, 5, 2.5, 1.25, 0.625, 0.312, 0.156, 0.078 mM/ Metal), it was found to have an inhibitory effect on the growth of these bacteria by microtiter plate method, especially when the concentration was increased. The size of the 16S rRNA gene in bacteria resistant to these metals varied at the half inhibitory concentration IC50 from the comparison sample with volume values of about 1500, 1000, 1000, 1500, 1500 , 1500, 1500, 1500, and 1000 base pairs, respectively.

Digestate from an Agricultural Biogas Plant as a Factor Shaping Soil Properties

In the context of a circular economy, special attention should be paid to the rational management of biodegradable waste. Currently, a potentially valuable waste material, rich in ingredients available to plants, is digestate, obtained as a by-product in agricultural biogas plants. The presented study aimed to determine the impact of digestate (DIG) from an agricultural biogas plant on soil reaction (pH), electrical conductivity (EC), sorption properties (SBC, HAC, CEC, BS), and chemical composition of soil. The research was based on a pot experiment in which increasing doses of liquid (LD) and solid (SD) forms of DIG were used in corn cultivation, balanced in terms of the amount of N introduced into the soil. The composition of DIG varied and depended on the LD or SD form. The LD was characterized by a lower pH value and higher EC compared to the SD form. The LD contained much less TC, fewer macroelements, and fewer trace elements. The application of LD significantly increased in the soil the content of TC, Ntot, available K, P, Fe, and Mn, and exchangeable cations K+. The SD significantly increased the content of available P, Mg, and Mn and exchangeable cations Ca2+ and Mg2+ in the soil. Both forms of digestate increased the total content of heavy metals (Cu, Cr, Pb, and Ni) in the soil. However, they did not pose a threat to the environment concerning their legally permissible levels.

Determination of Trace Heavy Metals Content of Various Herbal Drinks Marketed in Ilorin Metropolis, Nigeria

The study encompasses an evaluation of the health risk and hazard profiles of heavy metals contents in various herbal drinks (AGBO) products marketed in Ilorin metropolis, Nigeria. Twenty (20) herbal drinks samples from four (4) different study (saw-mil, Osere, Oja-oba and Oke-odo) areas were collected randomly, digested and analyzed. Zinc, Lead, Copper, Iron, Manganese, Cadmium, Chromium and Nickel were analyzed using Atomic Absorption Spectrometer. The results of this study indicated that most of the heavy metals (Zn, Pb, Cu and Mn) in the herbal drinks were below the WHO recommended permissible limits. Chromium (Cr) and Cadmium (Cd) are not detected in all of the herbal drinks analyzed. However, sample C2 and D2 among other analyzed herbal samples contained unsafe concentrations of iron (Fe) and nickel (Ni) that exceeded the WHO recommended permissible limits. From the health point of view, the EDIs value of all the herbal drinks are below the daily reference dose. The non-cancerous (HQ) and hazard index (HI) value of all the herbal samples are less than one (1). Based on the results obtained in this study, there would be a non-carcinogenic health risk and hazard effects to the people taking and consuming the herbal drinks marketed in all the study areas.

Comparative assessment of the effect of storage vessels, thatched roof and industrial activity on harvested rainwater quality in south eastern, Nigeria using water quality index

Rainwater is usually harvested through catchment systems such as roofs or directly from the sky for storage in different vessels for eventual use due to water scarcity which is as a result of increased in water demand, rapid industrialization, increasing pollution, global warming and climate change. This study was carried out to assess the effects of galvanized iron and PVC tanks, thatched roof and industrial activity on harvested rainwater quality by investigating physico-chemical properties, heavy metals, coliform level and metal composition of the storage vessels. Seven-two harvested rainwater samples were collected from four locations in the urban and rural areas of Delta and Enugu States, Nigeria between the months of April-July, 2018. Rainwater samples stored for 1 month to a year in storage vessels were considered. The results were compared with water quality standards (USEPA, WHO, NAFDAC and NSDWQ) and Water Quality Index ratings. Heavy metals (Pb, Fe, Cr, Zn and Al) were analyzed using Flame-AAS; other parameters were determined using standard methods. The WQI ratings were calculated using the weighted arithmetic method. The results were analysed using descriptive and two-way ANOVA statistical analysis. Results obtained in both areas of the States showed mean values ranging from 5.60 ± 0.28 to 7.60 ± 0.20 for pH, E.coli (0.00 ± 0.00–1.00 ± 0.00 cfu/mL), EC (7.00 ± 1.41–108.70 ± 8.62 µs/cm), colour (0.44 ± 0.01–12.86 ± 0.17 TCU) and heavy metals (mg/L) gave 0.00 ± 0.00–1.52 ± 0.13 for Fe, Pb (0.00 ± 0.00–0.29 ± 0.02), Cr (0.00 ± 0.00–0.30 ± 0.05), Zn (0.00 ± 0.00–0.05 ± 0.02) and Al (0.00 ± 0.00–4.65 ± 2.24). The results of the harvested rainwater samples analyzed showed that, the mean values of all the parameters analyzed were below and within the water quality set standard with the exception of a few in both areas in each of the States and were significantly different at (p < 0.05). The results of WQI ratings showed that, harvested rainwater qualities in both States were rated from excellent to unfit for drinking water quality. Generally, harvested rainwater stored in PVC tanks rated better than rainwater stored in galvanized iron tanks though not free of contamination. The storage duration for harvested rainwater is very important for its water quality, hence, harvested rainwater whether it is stored or not should be subjected to treatment before being use for potable usages.

Distribution characteristics, risk assessment, and source analysis of heavy metals in typical lake sediments in Inner Mongolia, China

As an important indicator of water pollution, heavy metals in lake sediments can reflect the severity of pollution in the entire study area. Although the risk assessment of heavy metals in sediment from various lakes has been widely studied, there is a lack of understanding on the overall pollution risk assessment of heavy metals in sediment from Inner Mongolia lakes located in cold and arid regions. This study based on data from 2019 to 2023 on heavy metals (Cu, Zn, Pb, Cr, and Cd) in typical lake sediments in Inner Mongolia, combining toxicity, ground accumulation index, and potential ecological risks with Monte Carlo simulation to evaluate lakes. Furthermore, the origins of heavy metals in lake sediments were quantitatively analyzed using a qualitative analysis and an absolute principal component core–multiple linear regression model. This study presented the following results. Firstly, according to the toxicity index, ground accumulation index, and potential ecological risk coefficient, Cd and Cr were identified as the most hazardous and toxic elements in typical lake sediments in Inner Mongolia. Secondly, the degree of lake pollution in Inner Mongolia followed a heavy to light gradient, with central > eastern > western. The pollution in western lakes primarily originated from natural factors, whereas central lakes were mainly affected by pollutants from industry, agriculture, and human activities. Eastern lakes experienced pollution primarily from animal husbandry activities and natural factors. The comprehensive analysis presented in this study can serve as a valuable reference for the restoration of polluted lakes.

Polyvinyl Alcohol‐Conjugated L‐Cysteine: A Novel Metal Pincer for Efficient Heavy Metal Ions Removal from Wastewater

AbstractA facilely prepared composite based on Polyvinyl alcohol anchored‐ L‐cysteine (PVA‐L‐CYS) demonstrated efficient functionality in the elimination of heavy metals (Hg, Cr, Pb, and Cd) from working wastewater. The synthesis of the composite was validated through a comprehensive characterization utilizing various analytical techniques to ensure the composite‘s structural, chemical, and physical properties. At ambient temperature, pH of 4–5.5, interaction time of 15–20 minutes, and concentration of 200 mg/L metal ions, the composite exhibited a maximum retention capacity of 48.5, 25, 45.25, and 44.25 mg/g for Hg, Cr, Pb, and Cd, respectively. Langmuir modeling was establish to be more fitting to the practical results than Freundlich, providing theoretical values of 49.02, 25.97, 46.08, and 44.84 mg/g for Hg, Cr, Pb, and Cd, respectively. The kinetics of PVA‐L‐CYS composite was accurately predicted by model of the pseudo‐first‐order kinetic. Thermodynamic prospects indicated a spontaneous, exothermic, and favorable uptake process at low temperatures. Efficient elution of the heavy metal ions from the overloaded composite was performed using 1 M HNO3. In accordance with WHO and FAO guidelines, the successful elimination of working metal ions from wastewater utilizing the PVA‐L‐CYS composite was demonstrated in a single cycle before discharge into the marine environment.

Rubus plicatus Weihe &amp;amp; Nees: resilience to pollution caused by stone quarries

This study aimed to analyze the effect of pollution caused by stone quarries on the morpho-anatomy, biochemistry, and physiology of a medicinal wild bramble Rubus plicatus Weihe &amp; Nees. Samples were collected from two natural protected areas: Iron Gates Natural Park and Jiu Gorge National Park, both located in the southwestern part of Romania, and two unpolluted areas from these parks as background sites. We carried out the following analyses on the collected leaves of this taxon: morphology, micromorphology, anatomy, assimilating pigments, heavy metals (Pb, Ni, Cr, Fe), dry mass, bioactive compounds (total phenols and flavonoids), and antioxidant capacity. The results showed more stomata, higher amounts of assimilating pigments, higher amounts of heavy metals (especially lead), less dry mass, less phenols, and more flavonoids in Rubus plicatus leaves from polluted areas compared to areas without sources of pollution. The increased number of stomata and the amounts of assimilator pigments revealed the mechanisms developed by this species in order to survive in polluted conditions.

Sulfonate-bridged semi-biopolyamide for Pb(II) electrochemical probing and dye adsorption

With the continuous development of modern industry, environmental problems accompanied by heavy metal Pb(II) and organic dyes become increasingly apparent, and the development of associated detection/removal materials has important practical significance thus. In this work, a novel biomass (diphenolic acid and furfurylamine)-based, polyamide-sulfonate cross-linked polymer (PA-df-OBSC) was successfully constructed. Further characterization of PA-df-OBSC indicated that the chemical structure of PA-df-OBSC consists of multiple N/O/S-containing molecular fragments as amide, tertiary amine, carboxylic acid, sulfonate ester and sulfonate acid. Such structural characteristic endows PA-df-OBSC dual functional application prospect. PA-df-OBSC can be applied as an enrichment-type Pb(II) electrochemical probe due to its specific complexation for Pb(II). The modified glassy carbon electrode (GCE) with PA-df-OBSC as active modifier presented a wide detection range (0.1–30 μmol/L) and low detection limit (1.31 × 10−8 M) for Pb(II). Besides, PA-df-OBSC also showed selective adsorption for cationic dye methylene blue (MB), with the maximum adsorption capacity up to 521.72 mg/g.

Unveiling the earthworm-associated preferential remediation of emerging organic pollutants and heavy metals in MSW-based vermicomposting systems: Insights through the lens of multivariate techniques and novel empirical models

Studies on the efficacies of vermicomposting and composting in countering the toxic impacts of pollutant cocktails in municipal solid waste (MSW) are scarce. Moreover, further research is needed to explore earthworms' remediation preferences for various pollutants in heterogeneous vermicomposting feedstocks, such as MSW. Therefore, removal dynamics of pesticides (chlorpyrifos, cypermethrin, and carbofuran), pharmaceuticals (diclofenac and carbamazepine), and heavy metals (Pb, Zn, Cu, and Mn) in MSW-based vermicomposting (Eisenia fetida and Eudrilus eugeniae) and composting systems were evaluated through multivariate analytical techniques (principal component (PCA) and multi-factor (MFA)) on the R-platform. Both earthworms satisfactorily increased their population and augmented NPK (nitrogen, phosphorous, and potassium) availability, cation exchange, microbial biomass C&N, and their metabolic activity 2–3 folds more than composting, accompanied by a 3–4 folds reduction of organic C, pH, and bulk density. Correspondingly, heavy metals, pesticides, and pharmaceuticals decreased by 8-10-folds via earthworm's significant pollutant removal efficiencies that subsided MSW-driven ecological risks by 60–90%. PCA and MFA revealed that N, P, and K-availability, organic C, and microbial activity were the indicative attributes for heavy metal and emerging organic micropollutant (EOMP)-removal during biocomposting; however, earthworms remove pesticides faster than pharmaceuticals and heavy metals. PCA-based novel empirical models demonstrated that in MSW-only feedstock, earthworm-mediated pollutant detoxification followed the order of pesticides > pharmaceuticals > heavy metals. However, in MSW combined with cow dung (1:1 ratio) feedstock, the detoxification order shifted to pharmaceuticals > heavy metals > pesticides. Therefore, this study provides fresh insights into pollutant-focused feedstock optimization for vermicomposting through model-based approaches, advancing the eco-friendly valorization of toxic MSW.