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1.
Environ Monit Assess ; 193(3): 109, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33537887

RESUMEN

Several commercial test kits such as Microtox, LUMIStox, ToxAlert, Aboatox, and ToxScreen have been widely used for toxicity screening. Though this time saving assays offer excellent sensitivity, cost-effectiveness, and accuracy, these commercial assays are limited in terms of real-time monitoring in Indian coastal environment due to warmer temperatures. This necessitates the need to develop a rapid and accurate assay that can be effectively employed for real time monitoring with respect to heavy metals in the Indian coastal waters. With this objective, the present study was conducted by isolating an indigenous luminescent bacterium from the light organs of chordates Gazza minuta which showed higher luminescence in a wide range of temperatures. The isolate could grow well in the temperature of 30 ± 2 °C and withstand temperature up to 35 ± 2 °C. The isolated bacterium was identified as Photobacterium leiognathi GoMGm1 based on 16S rDNA and luxA gene sequences. The suitable growing medium was optimized using central composite rotational design (CCRD) method to obtain optimal growth and luminescence. The optimized medium exemplified the maximal growth and luminescence of P. leiognathi at OD600 nm of 5.78 ± 0.12 and RLU of 12.49 ± 0.43. The isolate was used to assess the toxicity of several heavy metals. The IC50 values of 0.0051, 1.13, 1.37, 3.1, and 6.68 mg L-1 were observed for the Hg, Cr, Cu, Ni, and Zn, respectively, after 15 min of exposure. Results obtained from principal component analysis (PCA) displayed the present assay's compatibility with other luminescent bacterial assay and commercial Microtox™ assay. Thus, it would the right candidate as an early detection system for heavy metals in aquatic bodies in tropical countries. Schematic representation of the present study.


Asunto(s)
Mercurio , Metales Pesados , Animales , Monitoreo del Ambiente , Mediciones Luminiscentes , Metales Pesados/análisis , Metales Pesados/toxicidad , Photobacterium
2.
Environ Monit Assess ; 193(2): 82, 2021 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-33486539

RESUMEN

The aim of the present study was to examine the genotoxicity induced by water-soluble fractions of particulate matter (PM) and its potential relation with heavy metals. For this purpose, the genotoxicity induced on human peripheral lymphocytes by water-soluble PM2.5 (particles with aerodynamic diameter ≤ 2.5 µm) collected from the indoor air of various workplaces in Greece (n = 20), was examined by the Sister Chromatid Exchange (SCE) induction assay and assessed in relation to the concentrations of the heavy metals Cu, Pb, Mn, Ni, Co, Zn, Cr, and Cd. The number of SCEs per metaphase (SCEs/metaphase), as an indicator of genotoxicity, the proliferation rate index (PRI), as an indicator of cytostaticity, and the mitotic index (MI), as an indicator of cytotoxicity, were measured and assessed in three water-soluble fractions of PM2.5: the total water-soluble fraction WSA (filtered through 0.45 µm), the dissolved fraction WSB (filtered through 0.22 µm), and the non-chelexed dissolved fraction WSC (filtered through Chelex-100 resin). Results showed statistically significant number of SCEs/metaphase in all water-soluble PM2.5 fractions in relation to the control with large variabilities across the workplaces as a result of variations in indoor conditions, sources, and/or activities. The concentrations of genotoxicity were evaluated in terms of mass-normalized genotoxicity (SCEs/mg PM2.5), that represents the genotoxic potency of particles, and air volume-normalized genotoxicity (SCEs/m3 air), that reflects the inhalation risk for people working or spending much time in these microenvironments. Correlation and linear regression analyses were further employed in order to investigate the potential relationships between genotoxicity and the water-soluble concentrations of PM2.5-bounded heavy metals. According to the results, the highest mass-normalized genotoxicity values were found for PM2.5 from the photocopying center, whereas the highest air volume-normalized genotoxicity was found in tavern-2. Significant positive correlations between the genotoxicity and water-soluble metals were derived, highlighting the role that heavy metals play in the genotoxicity of indoor PM2.5. Among the targeted metals, Zn and Pb were found to be good predictors of the genotoxicity of water-soluble PM2.5.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Daño del ADN , Monitoreo del Ambiente , Grecia , Humanos , Metales Pesados/análisis , Metales Pesados/toxicidad , Material Particulado/análisis , Material Particulado/toxicidad , Agua
3.
Ecotoxicol Environ Saf ; 211: 111922, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33472110

RESUMEN

Human health is adversely affected by potentially toxic elements (PTEs) in the topsoil, entering the bodies via inhalation, ingestion, and dermal contact. To visualize human health risks, we investigated five PTEs (Cd, As, Pb, Hg, and Cr) in 72 farmland topsoil samples from a town in Chongqing City, southwest China. Based on the human health risk assessment model, sequential indicator simulation (SIS) and the positive matrix factorization model (PMF) were used to construct the spatial health risks and to analyze the sources of PTEs; finally, health risks were combined with the source by ArcGIS. Based on our results, the use of SIS is feasible for the prediction of the spatial distribution of PTEs. Among the risks, the non-cancer risk of As for children most likely exceeded the accepted level in some areas, making As a priority pollutant. Although the health risks of soil Cd were acceptable in the region, the spatial probability distribution of Cd> 0.3 mg/kg represents a threat as Cd enters the human food chain. Even if the industrial discharge was the lowest individual contributor (29.33%), due to the impact of industrial discharge, the total non-cancer risk with a high probability (>0.85) for children still exceeded the accepted level in the northwestern area, which should be regarded as the priority pollution source. The combined method was useful to reduce efforts in environmental management, thus providing a basis for soil remediation and pollution source control.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Granjas/estadística & datos numéricos , Metales Pesados/toxicidad , Contaminantes del Suelo/toxicidad , Niño , China , Ciudades , Simulación por Computador , Monitoreo del Ambiente/métodos , Contaminación Ambiental/estadística & datos numéricos , Humanos , Industrias , Mercurio , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
4.
Ecotoxicol Environ Saf ; 211: 111905, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33453636

RESUMEN

The constant increase of heavy metals into the aqueous environment has become a contemporary global issue of concern to government authorities and the public. The study assesses the concentration, distribution, and risk assessment of heavy metals in freshwater from the Linggi River, Negeri Sembilan, Malaysia. Species sensitivity distribution (SSD) was utilised to calculate the cumulative probability distribution of toxicity from heavy metals. The aquatic organism's toxicity data obtained from the ECOTOXicology knowledgebase (ECOTOX) was used to estimate the predictive non-effects concentration (PNEC). The decreasing sequence of hazardous concentration (HC5) was manganese > aluminium > copper > lead > arsenic > cadmium > nickel > zinc > selenium, respectively. The highest heavy metal concentration was iron with a mean value of 45.77 µg L-1, followed by manganese (14.41 µg L-1) and aluminium (11.72 µg L-1). The mean heavy metal pollution index (HPI) value in this study is 11.52, implying low-level heavy metal pollutions in Linggi River. The risk quotient (RQ) approaches were applied to assess the potential risk of heavy metals. The RQ shows a medium risk of aluminium (RQm = 0.1125) and zinc (RQm = 0.1262); a low risk of arsenic (RQm = 0.0122) and manganese (RQm = 0.0687); and a negligible risk of cadmium (RQm = 0.0085), copper (RQm = 0.0054), nickel (RQm = 0.0054), lead (RQm = 0.0016) and selenium (RQm = 0.0012). The output of this study produces comprehensive pollution risk, thus provides insights for the legislators regarding exposure management and mitigation.


Asunto(s)
Metales Pesados/toxicidad , Contaminantes Químicos del Agua/toxicidad , Arsénico/análisis , Cadmio/análisis , Cobre/análisis , Ecotoxicología , Monitoreo del Ambiente , Agua Dulce , Hierro , Malasia , Manganeso , Metales Pesados/análisis , Níquel/análisis , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/análisis , Zinc/análisis
5.
Aquat Toxicol ; 231: 105732, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33385847

RESUMEN

River biofilms are a suitable indicator of toxic stress in aquatic ecosystems commonly exposed to various anthropogenic pollutants from industrial, domestic, and agricultural sources. Among these pollutants, heavy metals are of particular concern as they are known to interfere with various physiological processes of river biofilm, directly or indirectly related to photosynthetic performance. Nevertheless, only limited toxicological data are available on the mechanisms and toxicodynamics of heavy metals in biofilms. Pulse Amplitude Modulated (PAM) fluorometry is a rapid, non-disruptive, well-established technique to monitor toxic responses on photosynthetic performance, fluorescence-kinetics, and changes in yield in other non-photochemical processes. In this study, a new micro-PAM-sensor was tested to assess potential acute and chronic effects of heavy metals in river biofilm. Toxicity values across the three parameters considered in this study (photosynthetic yield YII, non-photochemical quenching NPQ, and basal fluorescence F0) were comparable, as determined EC50 were within one order of magnitude (EC50 ∼1-10 mg L-1). However, the stimulation of NPQ was more clearly associated with early acute effects, especially in illuminated samples, while depression of YII and F0 were more prevalent in chronic tests. These results have implications for the development of functional indicators for the biomonitoring of aquatic health, in particular for the use of river biofilm as a bioindicator of water quality. In conclusion, the approach proposed seems promising to characterize and monitor the exposure and impact of heavy metals on river periphyton communities. Furthermore, this study provides a fast, highly sensitive, inexpensive, and accurate laboratory method to test effects of pollutants on complex periphyton communities that can also give insights regarding the probable toxicological mechanisms of heavy metals on photosynthetic performance in the river biofilm.


Asunto(s)
Técnicas Biosensibles , Exposición a Riesgos Ambientales , Fluorometría/instrumentación , Metales Pesados/toxicidad , Ríos/química , Biopelículas/efectos de los fármacos , Chlorophyta/citología , Chlorophyta/efectos de los fármacos , Diatomeas/citología , Diatomeas/efectos de los fármacos , Monitoreo del Ambiente , Fluorescencia , Perifiton/efectos de los fármacos , Procesos Fotoquímicos , Fotosíntesis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Contaminación del Agua/análisis , Calidad del Agua
6.
Ecotoxicol Environ Saf ; 208: 111679, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396011

RESUMEN

A comprehensive study on concentration, spatial distribution, pollution, ecological-health risk and source of potentially toxic elements (PTEs) in dust of residential area in Xi'an, China were conducted to explore the environmental quality of residential area in urban district. The results show that the concentrations of V, Ni, and Mn in the dust were less than, while the contents of Cr, Zn, Pb, Cu, and Ba in the dust were obviously larger than, the soil background values of Shaanxi. The high-value area of PTEs primarily concentrated in densely populated areas, heavily trafficked areas and the surroundings of plants. Cr, Pb and Zn posed moderate enrichment and Pb possessed moderate ecological risk in the dust. The comprehensive pollution levels of PTEs in the dust were uncontaminated to moderately contaminated and their comprehensive ecological risk were moderate. The non-carcinogenic risks of the PTEs for adults and children were in the safe level and the carcinogenic risks of Ni and Cr were under the current acceptable value. Four major sources were discriminated on basis of the multivariate statistical analysis results and the content characteristics, enrichment degrees, and the spatial distribution features of the PTEs, viz. Mn, V, and Ni primarily came from natural source; Pb, Zn, and Cu mainly originated from traffic source; and Ba and Cr were respectively from construction source and coal-fired power plant source, which respectively contributed 22.8%, 28.3%, 47.3%, and 1.6% to the total content of PTEs determined in the dust.


Asunto(s)
Polvo/análisis , Monitoreo del Ambiente/métodos , Contaminación Ambiental , Metales Pesados , Adulto , Carcinógenos/análisis , Carcinógenos/toxicidad , Niño , China , Contaminación Ambiental/efectos adversos , Contaminación Ambiental/análisis , Humanos , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Urbanización
7.
Ecotoxicol Environ Saf ; 208: 111634, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396154

RESUMEN

The Quantitative Structure-Activity Relationship (QSAR) has been used to investigate organic mixtures but QSAR in the nanomaterial field (QNAR) is still new. Toxicity is a result of the interaction of many substances. QNAR research focuses on a single nanomaterial in the long-term. It is difficult to find an appropriate descriptor to build a model due to the complexity of the mixture. Here, we attempt to build a QNAR model to predict cell viability for HK-2 cells exposed to a mixture containing nano-TiO2 and heavy metals. HK-2 cells were exposed to four groups of mixtures containing heavy-metals and nanomaterials and CCK8 was added to obtain the number of living cells. At the same time, ROS was investigated to study this mechanism. Each descriptor of the components and mixtures were obtained using the formula Dmix= [Formula: see text] respectively. We used the Multiple Partial Least Squares Regression (PLS) and Random Forest Regression (RF) to build a QNAR model. Both models reliably predict and assess viability of HK-2 cells exposed to the mixture. The RF model showed greater stability and higher precision in toxicity predictability and can be applied to environmental nano-toxicology.


Asunto(s)
Ecotoxicología/métodos , Metales Pesados/toxicidad , Nanoestructuras/toxicidad , Relación Estructura-Actividad Cuantitativa , Titanio/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Metales Pesados/química , Nanoestructuras/química , Especies Reactivas de Oxígeno/metabolismo , Titanio/química
8.
Ecotoxicol Environ Saf ; 208: 111750, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396075

RESUMEN

Contamination of agricultural land and water by heavy metals due to rapid industrialization and urbanization including various natural processes have become one of the major constraints to crop growth and productivity. Several studies have reported that to counteract heavy metal stress, plants should be able to maneuver various physiological, biochemical and molecular processes to improve their growth and development under heavy metal stress. With the advent of modern biotechnological tools and techniques it is now possible to tailor legume and other plants overexpressing stress-induced genes, transcription factors, proteins, and metabolites that are directly involved in heavy metal stress tolerance. This review provides an in-depth overview of various biotechnological approaches and/or strategies that can be used for enhancing detoxification of the heavy metals by stimulating phytoremediation processes. Synthetic biology tools involved in the engineering of legume and other crop plants against heavy metal stress tolerance are also discussed herewith some pioneering examples where synthetic biology tools that have been used to modify plants for specific traits. Also, CRISPR based genetic engineering of plants, including their role in modulating the expression of several genes/ transcription factors in the improvement of abiotic stress tolerance and phytoremediation ability using knockdown and knockout strategies has also been critically discussed.


Asunto(s)
Productos Agrícolas/fisiología , Fabaceae/fisiología , Metales Pesados/toxicidad , Contaminantes del Suelo/toxicidad , Biodegradación Ambiental , Biotecnología , Productos Agrícolas/metabolismo , Fabaceae/metabolismo , Metales Pesados/análisis , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Estrés Fisiológico , Verduras/metabolismo
9.
Ecotoxicol Environ Saf ; 208: 111769, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396087

RESUMEN

Soils contaminated with heavy metals such as Chromium (Cr) and Cadmium (Cd) severely impede plant growth. Several rhizospheric microorganisms support plant growth under heavy metal stress. In this study, Cr and Cd stress was applied to in vitro germinating seedlings of a Legume plant species, Sesbania sesban, and investigated the plant growth potential in presence and absence of Bacillus anthracis PM21 bacterial strain under heavy metal stress. The seedlings were exposed to different concentrations of Cr (25-75 mg/L) and Cd (100-200 mg/L) in Petri plates. Growth curve analysis of B. anthracis PM21 revealed its potential to adapt Cr and Cd stress. The bacteria supported plant growth by exhibiting ACC-deaminase activity (1.57-1.75 µM of α-ketobutyrate/h/mg protein), producing Indole-3-acetic acid (99-119 µM/mL) and exopolysaccharides (2.74-2.98 mg/mL), under heavy metal stress condition. Analysis of variance revealed significant differences in growth parameters between the seedlings with and without bacterial inoculation in metal stress condition. The combined Cr+Cd stress (75 + 200 mg/L) significantly reduced root length (70%), shoot length (24%), dry weight (54%) and fresh weight (57%) as compared to control. Conversely, B. anthracis PM21 inoculation to seedlings significantly increased (p ≤ 0.05) seed germination percentage (5%), root length (31%), shoot length (23%) and photosynthetic pigments (Chlorophyll a: 20%; Chlorophyll b: 16% and total chlorophyll: 18%), as compared to control seedlings without B. anthracis PM21 inoculation. The B. anthracis PM21 inoculation also enhanced activities of antioxidant enzymes, including superoxide dismutase (52%), peroxidase (66%), and catalase (21%), and decreased proline content (56%), electrolyte leakage (50%), and malondialdehyde concentration (46%) in seedlings. The B. anthracis PM21 inoculated seedlings of S. sesban exhibited significantly high (p ≤ 0.05) tissue deposition of Cr (17%) and Cd (16%) as compared to their control counterparts. Findings of the study suggested that B. anthracis PM21 endured metal stress through homeostasis of antioxidant activities, and positively impacted S. sesban growth and biomass. Further experiments in controlled conditions are necessary for investigating phytoremediation potential of S. sesban in metal-contaminated soils in presence of B. anthracis PM21 bacterial strain.


Asunto(s)
Bacillus anthracis/fisiología , Metales Pesados/toxicidad , Sesbania/fisiología , Contaminantes del Suelo/toxicidad , Bacillus anthracis/metabolismo , Biodegradación Ambiental , Cadmio/metabolismo , Catalasa/metabolismo , Clorofila , Clorofila A/metabolismo , Cromo/análisis , Germinación/efectos de los fármacos , Ácidos Indolacéticos , Metales Pesados/análisis , Plantones/metabolismo , Sesbania/metabolismo , Sesbania/microbiología , Suelo , Contaminantes del Suelo/análisis
10.
Ecotoxicol Environ Saf ; 208: 111567, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396096

RESUMEN

In this study, the production and compositional analysis of exopolysaccharides produced by Bacillus cereus KMS3-1 grown in metal amended conditions were investigated. In addition, the metal adsorption efficacy of exopolysaccharides (EPS) produced by KMS3-1 strain was evaluated in a batch mode. Increased production of exopolysaccharides by KMS3-1 strain was observed while growing under metal amended conditions (100 mg/L) and also, the yield was in the order of Pb(II)>Cu(II)>Cd(II)>Control. Characterization of EPS using FT-IR, XRD, and SEM analysis revealed that the EPS can interact with metal ions through their functional groups (O‒H, CH, CË­O, C‒O, and C‒CË­O) and assist the detoxification process. Further, equilibrium results were fitted with the Langmuir model and notably, the maximum adsorption capacity (Qmax) of EPS for Cd(II), Cu(II), and Pb(II) found to be 54.05, 71.42, and 78.74 mg/g, respectively. To the best of our knowledge, EPS demonstrating proficient metal adsorption was substantiated by XRD analysis in this study. Owing to good adsorbing nature, the exopolysaccharides could be used as chelating substances for wastewater treatment.


Asunto(s)
Metales Pesados/toxicidad , Polisacáridos Bacterianos , Adsorción , Bacterias , Quelantes , Polisacáridos , Espectroscopía Infrarroja por Transformada de Fourier
11.
Ecotoxicol Environ Saf ; 208: 111618, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396138

RESUMEN

Air pollution has been recognized to be a risk factor for lung cancer. The objective of this study was to investigate the effects of air pollution on heavy metal alterations in the pleural effusion of lung cancer patients. Pleural effusion was collected from patients with lung cancer and congestive heart failure (CHF). One-year average levels of particulate matter with an aerodynamic diameter of < 10 µm (PM10), PM2.5, NO2, and SO2 were linked to the exposure of these subjects. Traffic-related metals, included Al, Fe, Cu, Zn, and Pb, were determined in the pleural effusion. Logistic regression models were used to examine their associations. There were 63 lung cancer patients and 31 CHF patients enrolled in the current study. We found that PM10, PM2.5, and NO2 were negatively correlated with Al in the pleural effusion, whereas PM2.5 was positively correlated with Zn in the pleural effusion. Increases in 1 µg/m3 of PM2.5 and 1 ng/mL of Zn were associated with lung cancer (adjusted OR=2.394, 95% CI= 1.446-3.964 for PM2.5; adjusted OR=1.003, 95% CI=1.000-1.005 for Zn). Increases in PM2.5 and Zn in the pleural effusion increased the risk of malignant pleural effusion in lung cancer patients (adjusted OR=1.517; 95% CI=1.082-2.127 for PM2.5; adjusted OR=1.002, 95% CI=1.000-1.005 for Zn). Furthermore, we observed that adenocarcinomas increased in association with a 1-µg/m3 increase in PM2.5 (crude OR=1.683; 95% CI=1.006-2.817) in lung cancer patients. In conclusion, PM2.5 exposure and the possible resultant Zn in the pleural effusion associated with the development of malignant pleural effusion in lung cancer.


Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Neoplasias Pulmonares/epidemiología , Metales Pesados/análisis , Material Particulado/análisis , Derrame Pleural Maligno/epidemiología , Anciano , Contaminantes Atmosféricos/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Metales Pesados/toxicidad , Persona de Mediana Edad , Tamaño de la Partícula , Material Particulado/toxicidad , Derrame Pleural Maligno/química , Derrame Pleural Maligno/patología , Factores de Riesgo , Taiwán
12.
Environ Monit Assess ; 193(1): 20, 2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33389235

RESUMEN

Soil heavy metal (Cr, Cu, Zn, Pb, Cd, V, As) concentrations in different areas were analyzed to investigate the effects of different industrial activities on heavy metal pollution status, potential ecological risk, and human health risk in Panzhihua. Our results showed that Cu and V enrichment in soil was due to ore smelting. Soil Cr accumulation was related to coal ore mining. Soil Cd, Zn, As, and Pb enrichment was attributed to high-temperature coal combustion. Under the effect of industrial activities, soils were moderately contaminated with Cd, uncontaminated to moderately contaminated with As and Zn, and uncontaminated with Cr, Cu, V, and Pb. Soil heavy metal potential ecological risk was considerable, and non-carcinogenic risks and carcinogenic risks of soil heavy metals were acceptable for adults but unacceptable for children. Thermal power generation was the dominated industrial activity that influence the soil heavy metal concentrations and environmental risks in Panzhihua, which posed considerable potential ecological risks and unacceptable heavy metal non-carcinogenic risks and As carcinogenic risk to both adults and children. This study indicates that industrial activities have great effects on heavy metal pollution, ecological risks, and health risk, and more attention should be paid to the ecological risk and health risks brought by thermal power generation.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Niño , China , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
13.
Ecotoxicol Environ Saf ; 208: 111685, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396017

RESUMEN

The wastewater utilization for irrigation purposes is common practice in peri-urban areas located in vicinity of developed cities. This water contains elements like chromium (Cr), nickel (Ni), cadmium (Cd) and nitrate (NO3-N) that poses health risk when exposed to human. In this study effect of wastewater irrigation from Chakara wastewater plant, Faisalabad on growth of wheat and health risks was assessed. Pot experiment was conducted at Institute of Soil and Environmental, University of Agriculture, Faisalabad using different concentration of wastewater as treatment 100% tap water, 25% wastewater + 75% tap water, 50% wastewater + 50% tap water, 75% wastewater + 25% tap water, 100% wastewater. The results indicated that the wastewater irrigation negatively effects the plant growth and physiological parameters. The minimum plant height, grain weight, spike length, osmotic potential and SPAD values were recorded 50.33 cm, 1.47 g plant-1, 7.00 cm, 423 and 38.91 respectively in 100% wastewater irrigation. The risk quotient (RQ TEs) for each toxic element and cumulative risk index (RI TEs) values were calculated. The cadmium risk quotient (Cd RQ) for adults was on margin and value was >1 for in 75% wastewater + 25% tap water and 100% wastewater irrigation, while the RQ for Ni and Cr was <1. Maximum RI TEs values calculated in 100% wastewater irrigation 0.424 and 0.294 for children and adults respectively. Hence it was concluded that wastewater irrigation significantly increased the accumulation rate of metals and nitrate in wheat and cause potential health risks for children and adults.


Asunto(s)
Riego Agrícola/métodos , Bioacumulación/efectos de los fármacos , Metales Pesados/toxicidad , Nitratos/toxicidad , Contaminantes del Suelo/toxicidad , Triticum/efectos de los fármacos , Aguas Residuales/química , Adulto , Cadmio/análisis , Cadmio/toxicidad , Niño , Cromo/análisis , Cromo/toxicidad , Ciudades , Grano Comestible/química , Humanos , Metales Pesados/análisis , Modelos Teóricos , Níquel/análisis , Níquel/toxicidad , Nitratos/análisis , Pakistán , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Aguas Residuales/análisis
14.
Environ Pollut ; 271: 116317, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33383416

RESUMEN

The effect of land application of sewage sludge on soil microbial communities and the possible spread of antibiotic- and metal-resistant strains and resistance determinants were evaluated during a 720-day field experiment. Enzyme activities, the number of oligotrophic bacteria, the total number of bacteria (qPCR), functional diversity (BIOLOG) and genetic diversity (DGGE) were established. Antibiotic and metal resistance genes (ARGs, MRGs) were assessed, and the number of cultivable antibiotic- (ampicillin, tetracycline) and heavy metal- (Cd, Zn, Cu, Ni) resistant bacteria were monitored during the experiment. The application of 10 t ha-1 of sewage sludge to soil did not increase the organic matter content and caused only a temporary increase in the number of bacteria, as well as in the functional and structural biodiversity. In contrast to expectations, a general adverse effect on the tested microbial parameters was observed in the fertilized soil. The field experiment revealed a significant reduction in the activities of alkaline and acid phosphatases, urease and nitrification potential. Although sewage sludge was identified as the source of several ARGs and MRGs, these genes were not detected in the fertilized soil. The obtained results indicate that the effect of fertilization based on the recommended dose of sewage sludge was not achieved.


Asunto(s)
Metales Pesados , Microbiota , Contaminantes del Suelo , Farmacorresistencia Microbiana/genética , Metales Pesados/análisis , Metales Pesados/toxicidad , Aguas del Alcantarillado , Suelo , Contaminantes del Suelo/análisis
15.
Environ Pollut ; 271: 116357, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33383422

RESUMEN

Aquatic organisms that inhabit coastal environments are generally exposed to multiple mixtures of chemicals. The single and mixture toxicity of nine trace metals (As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, and Zn) to the rotifer Proales similis were examined at four different salinities (5, 15, 25, and 35 ppt). Chronic toxicity reproductive tests were performed using an application factor (AF) of 0.05, 0.1, 0.2, and 0.4 by multiplying the 24-h LC50 values of each metal. The metal mixture treatments were: T1, As-Cd-Cr-Cu-Fe-Hg-Ni-Pb-Zn; T2, As-Cd-Hg-Pb and; T3, Cr-Cu-Fe-Ni-Zn. The LC50 values ranged between 5 and 4140 µg L-1 in the following order: Hg > Cu > Fe > Pb > Cd > Zn > As > Cr > Ni in low salinity and Hg > Cu > Fe > Pb > Zn > As > Cd > Cr > Ni in high salinity conditions. In all cases, acute toxicity was higher at a salinity of 5 ppt compared to 35 ppt. Chronic toxicity tests indicated that single metal toxicity intensified as the AF increased and as salinity decreased. Regardless of salinity, Pb at 0.4 AF was the most toxic metal. Proales similis evidenced a higher growth in the As treatments (0.1 and 0.2 AF) at 35 ppt compared to controls. Furthemore, the T1 and T2 treatments were the most toxic, and in most cases, they induced a synergistic effect. Antagonism effects were detected in the T3 treatment at 25 and 35 ppt. The present data highlights the importance of the examination of pollution in natural environmental conditions in which many aquatic invertebrates endure.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Animales , Cadmio , Monitoreo del Ambiente , Plomo/toxicidad , Metales Pesados/análisis , Metales Pesados/toxicidad , Salinidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Zinc
16.
Plant Physiol Biochem ; 159: 100-112, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33359959

RESUMEN

At the dawn of the industrial revolution, the exorbitant use of heavy metals and toxic elements by mankind unfurls a powerful and complex web of hazard all around the world that significantly contributed to unprecedented trends in environmental degradation. Plants as sessile organisms, that cannot escape from the stress directly, have adapted to this environment via concurrent configurations of several traits. Among them the anatomy has been identified as much more advanced field of research that brought the explosion of interest among the expertise and its prodigious importance in stress physiology is unavoidable. In conjunction with various other disciplines, like physiology, biochemistry, genomics and metabolomics, the plant anatomy provides a large data sets that are paving the way towards a comprehensive and holistic understanding of plant growth, development, defense and productivity under heavy metal and toxic element stress. Present paper advances our recent knowledge about structural alterations of plant tissues induced by metals and metalloids, like antimony (Sb), arsenic (As), aluminium (Al), copper (Cu), cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni) and zinc (Zn) and points on essential role of plant anatomy and its understanding for plant growth and development in changing environment. Understanding of anatomical adaptations of various plant organs and tissues to heavy metals and metalloids could greatly contribute to integral and modern approach for investigation of plants in changing environmental conditions. These findings are necessary for understanding of the whole spectra of physiological and biochemical reactions in plants and to maintain the crop productivity worldwide. Moreover, our holistic perception regarding the processes underlying the plant responses to metal(loids) at anatomical level are needed for improving crop management and breeding techniques.


Asunto(s)
Exposición a Riesgos Ambientales , Metaloides , Metales Pesados , Plantas , Metaloides/toxicidad , Metales Pesados/toxicidad , Organogénesis de las Plantas/efectos de los fármacos , Plantas/anatomía & histología , Plantas/efectos de los fármacos
17.
Aquat Toxicol ; 231: 105708, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33341508

RESUMEN

The WHAM-FTOX model quantifies cation toxicity towards freshwater organisms, assuming an additive toxic response to the amounts of protons and metals accumulated by an organism. We combined a parameterization of the model, using data from multi-species laboratory toxicity tests, with a fitted field species sensitivity distribution, to simulate the species richness (nsp) of crustacean zooplankton in acid- and metal-contaminated lakes near Sudbury, Ontario over several decades, and also in reference (uncontaminated) lakes. A good description of variation in toxic response among the zooplankton species was achieved with a log-normal distribution of a new parameter, ß, which characterizes an organism's intrinsic sensitivity towards toxic cations; the greater is ß, the more sensitive is the species. The use of ß assumes that while species vary in their sensitivity, the relative toxicities of different metals are the same for each species (common relative sensitivity). Unbiased agreements between simulated and observed nsp were obtained with a high correlation (r2 = 0.81, p < 0.0001, n = 217). Variations in zooplankton species richness in the Sudbury lakes are calculated to be dominated by toxic responses to H, Al, Cu and Ni, with a small contribution from Zn, and negligible effects of Cd, Hg and Pb. According to the model, some of the Sudbury lakes were affected predominantly by acidification (H and Al), while others were most influenced by toxic heavy metals (Ni, Cu, Zn); for lakes in the latter category, the relative importance of heavy metals, compared to H and Al, has increased over time. The results suggest that, if common relative sensitivity operates, nsp can be modelled on the basis of a single set of parameters characterizing the average toxic effects of different cations, together with a species sensitivity distribution.


Asunto(s)
Ácidos/toxicidad , Biodiversidad , Laboratorios , Lagos/química , Metales Pesados/toxicidad , Modelos Teóricos , Contaminantes Químicos del Agua/toxicidad , Zooplancton/fisiología , Animales , Organismos Acuáticos/efectos de los fármacos , Crustáceos/efectos de los fármacos , Monitoreo del Ambiente , Ontario , Especificidad de la Especie , Estadística como Asunto , Factores de Tiempo , Zooplancton/efectos de los fármacos
18.
Sci Total Environ ; 762: 144180, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33360463

RESUMEN

Toxicity interaction, synergism and antagonism, may occur when multiple pollutants are exposed to the environment simultaneously, which limits the utility of some standard models to assess toxicity hazards and risks. The development and application of models which can provide an insight into the combined toxicity of pollutants becomes necessary. Therefore, a novel model, area-concentration ratio (ACR) method, was developed to characterize the toxicity interaction within mixtures of three aminoglycoside antibiotics (AGs), kanamycin sulfate (KAN), paromomycin sulfate (PAR), tobramycin (TOB) and one heavy metal copper (Cu) in this study. The inhibition toxicity of single contaminants and mixtures designed by direct equilibration ray method and uniform design ray method to Chlorella pyrenoidosa (C. pyrenoidosa) was determined by the microplate toxicity analysis (MTA). The results showed that the novel method ACR could be used for quantitative characterization of combined toxicity. According to the ACR, all the binary AG antibiotic mixture systems display obvious synergism and weak antagonism. The addition of the heavy metal Cu into binary AG antibiotic mixtures can obviously change toxicity interaction, but toxicity interaction changing trend varies greatly in different ternary mixture systems. Toxicity interaction in the six mixture systems has component concentration-ratio dependence. ACR can be suggested as an effective novel method to quantitatively characterize toxicity interaction when assessing the hazards and risks of the combined pollution.


Asunto(s)
Chlorella , Metales Pesados , Antibacterianos/toxicidad , Cobre/toxicidad , Interacciones Farmacológicas , Metales Pesados/toxicidad
19.
Ecotoxicol Environ Saf ; 209: 111808, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33360289

RESUMEN

One of the fundamental objectives in modern ecology is to decipher how bacterial communities in natural environment respond to anthropogenic activities. In recent times consequences of marine pollution, especially with heavy metals (HMs) have received increasing attention. However, insights into the response of bacterial communities to HMs in coastal sediments of India remain scarce. Here, we analyzed HMs content in three areas, along the southern coastal region of India. Based on the calculated pollution indices viz., enrichment factor (EF), contamination factor (CF), geo-accumulation index (Igeo) and sediment quality guidelines (SQGs), the studied areas were classified as uncontaminated, moderately contaminated and significantly contaminated. To explore the response of bacterial community to HMs, sediment-associated microbiota was investigated using high-throughput 16S rRNA gene amplicon sequencing. The obtained metataxonomic results revealed that bacterial diversity and community composition varied considerably in significantly contaminated area than moderately contaminated and uncontaminated areas. Proportion of bacterial classes was higher for Gammaproteobacteria, Betaproteobacteria and Actinobacteria, but lower for Alphaproteobacteria and Flavobacteriia in significantly contaminated area. Also, samples of significantly contaminated area were dominated by well-documented metal-resistant bacterial genera such as Ralstonia and Arthrobacter. Canonical correspondence analysis (CCA) showed that spatial variability of bacterial community composition was strongly correlated with HMs content such as Chromium, Cadmium and Nickel. Further analysis using PICRUSt programme indicated that the predictive functional profile also varied considerably in significantly contaminated area. By linking HMs with bacterial compositional variations, the present study highlights the likely influence of HMs in shaping sedimentary microbiota of coastal regions.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/microbiología , Metales Pesados/toxicidad , Contaminantes Químicos del Agua/toxicidad , Bacterias , Cadmio/análisis , Cromo/análisis , Ecología , Contaminación Ambiental/análisis , Sedimentos Geológicos/química , India , Metales Pesados/análisis , Microbiota , Níquel/análisis , ARN Ribosómico 16S , Contaminantes Químicos del Agua/análisis
20.
Sci Total Environ ; 759: 144023, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33340857

RESUMEN

Boundaries between industrial and urban areas in developing countries are not clearly defined, but pollution effect assessment of industrial activities on potentially toxic metal (PTM) distribution in these areas has rarely been investigated. Fifteen villages and eight communities surrounding the industrial areas from Anyang, China, were chosen as research objects in this study. A total of 78 windowsill dust and 78 surface soil samples were collected to determine the pollution levels, spatial distribution and risk indices of nine PTMs. PTM concentrations (expect Cr, Mn and Ni in surface soil) in the surveyed region were higher than the local soil background values. Amongst these PTMs, serious Cd and As pollution was discovered, and Cd and As in windowsill dust and surface soil exceeded the background value by 73.00 and 9.59, 9.74 and 10.92 times, respectively. Compared with the Igeo in surface soil, a large degree of variation in Igeo for the different PTMs was found in windowsill dust. The interpolated spatial distribution of dust Cr, Zn, Pb, Cd and soil Mn, Ni and Cu had a gradually decreasing pollution trend from the south to the north due to the prevailing wind directions in winter in the study area. Results of multivariate statistics reflected that industrial production and traffic emission affected the concentration of PTMs in windowsill dust and surface soil. The non-carcinogenic risks for children (soil: 12.4; dust: 19.2) were larger than those for adults (soil: 1.02; dust: 1.51). This finding suggested that industrial activities caused serious harm to the residents around industrial areas.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Niño , China , Ciudades , Polvo/análisis , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Metales Pesados/toxicidad , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
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