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This study compared Lead (Pb), Chromium (Cr), Copper (Cu), Zinc (Zn), Mercury (Hg), Arsenic (As) and Cadmium (Cd) concentrations in sediment, water, and biota at Vaughan Dam which receives limited sewage effluent discharge from residential areas, and Korle Lagoon which receives industrial effluents, electronic waste, garages-spill oil and a host of others in addition to residential sewage effluent discharge. Samples were analyzed with Atomic Absorption Spectrometer. The results showed that concentrations of trace metals were generally higher in the sediment, water, and plants from the Korle Lagoon but only Cu in the sediment of Korle Lagoon showed a significantly high concentration. The similarities in the rank orders of the metal concentrations together with the dominance of Zn and Pb in most compartments of the wetlands indicated major differences did not exist in the contaminant input to the two wetlands except electronic waste recycling and disposal that resulted in significantly high copper concentrations in the sediment of Korle Lagoon. No evidence of biomagnification was determined along the food chains of the Vaughan Dam and the Korle Lagoon for all the metals studied.The Tilapia zilli from Vaughan Dam, the only biota that is regularly consumed from the wetlands, had Cr, Cu, Pb, Cd, Hg, and As concentrations above FAO/WHO permissible limits and therefore pose a health risk to consumers.
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Arsénico , Mercurio , Oligoelementos , Cobre , Ghana , Cadmio , Plomo , Aguas del Alcantarillado , Humedales , Monitoreo del Ambiente , Zinc , CromoRESUMEN
The input of trace elements from a small urban river (Las River, Toulon, France) located on the northern Mediterranean coast was studied during both base flow and flood events. A 2-year monitoring period of water flow and suspended particulate matter (SPM) showed a typical Mediterranean hydrological regime: a strong increase in water flow and SPM during short flood periods. During the flood event, an up to 2-fold increase in dissolved trace element (DTM) concentrations and particulate trace element content in SPM (PTM) was observed compared to the baseline discharge. The enrichment factor of elements in the SPM ranges from low or moderate for Co, Ni and Cr (1.0-4.7) to extremely high for Cd (157). However, the enrichment factors decrease from base flow to flood, indicating a dilution effect with a large yield of weathering particles with higher particle size. The most significant total trace element loading occurred during flood, ranging from 78% for As and Ni to 91% for Pb, while PTM loading during flood ranged from 35% for As to 77% for Pb. The specific dissolved fluxes during the flood are significantly higher for Pb, Cu and Zn than in the surrounding rivers, indicating specificity in the catchment (lithology). This study shows the importance of monitoring the transport of pollutants through small urban rivers and their potential impact on the coastal region, especially when they enter small and closed bays, as a receiving pool.
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Oligoelementos , Plomo , Ríos , Monitoreo del Ambiente , Material Particulado , AguaRESUMEN
Lead (Pb) is a non-essential metal with high toxicity, is persistent, is not biodegradable, and has no known biological function. It is responsible for severe health and environmental issues that need appropriate remediation. Therefore, microbes have thrived in a lead-contaminated environment without exhibiting any negative impacts. The present study aimed to examine the toxic effects of lead on animals and the isolation, identification, and characterization of lead-resistant bacterial strains and their biodegradation potential. After oral administration of lead for 4 weeks, mice showed an elevated level of leukocytes and a decrease in TEC, Hb, PCV, MCV, MCH, and MCHC levels. However, a decline in body weight and inflammation and oxidative stress was observed in liver tissues. To remediate toxic heavy metal, lead-resistant bacterial strains were isolated, among which Enterobacter exhibited maximum degradation potential at high lead concentrations. It was identified by molecular basis and after 16S rRNA sequencing, and 99% resemblance was observed with Enterobacter cloacae. FT-IR analysis of the bacteria illustrated the presence of functional groups, including hydroxyl, carboxyl group, sulfide, and amino groups, on the bacterial cell surface involved in the adsorption of lead. Moreover, electron microscopy (SEM) revealed the morphological and physiochemical changes in the bacterial cell after biosorption, indicating the interaction of Cu ions with functional groups. To summarize, the findings show the highly toxic effects of lead on animals and humans and its effective biodegradation by the bacterial strains in the lead-contaminated environment. This biological strategy can be an ideal alternative to remediate heavy metals from contaminated sites to clean up the environment.
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Plomo , Metales Pesados , Humanos , Animales , Ratones , Biodegradación Ambiental , ARN Ribosómico 16S , Espectroscopía Infrarroja por Transformada de Fourier , Monitoreo del Ambiente , Metales Pesados/toxicidadRESUMEN
The concentrations of mercury (Hg) and lead (Pb) in feather samples of nine bird's species (n = 65) were determined from southeastern areas of Iran, Hamun International Wetlands. Hg concentrations were ranged from 0.40 to 3.00 mg/kg dry wt and from 0.38 to 1.76 mg/kg for primary and secondary feathers, respectively. Furthermore, Pb concentrations were ranged from 1.43 to 4.10 mg/kg and from 1.28 to 3.65 mg/kg for primary and secondary feathers, respectively. Deposition of metals varied significantly among the primary and secondary feathers of systematic category (families) for Hg and Pb (p < 0.001). It was found that there is a significant difference in feather Hg and Pb concentrations across species (p < 0.001) with highest concentrations in saker falcon (Falconidae) (Hg = 3.00 mg/kg and Pb = 4.10 mg/kg, primary feather) followed by little owl (Strigidae). Grey francolin (Phasianidae) contained the least amount of Hg (0.40 mg/kg) and Pb (1.43 mg/kg) in primary feather. The results showed that the highest concentrations of heavy metals were related to carnivores. Fish predators, omnivores, and insectivores were examined at the next level of metal concentration, with herbivores having the lowest concentrations of lead (1.43 mg/kg) and mercury (0.40 mg/kg). Birds with an open grasslands feeding strategy had the highest mercury and lead concentration. The average value for Pb was on the border of harmful effects (4 mg/kg). The results of this study indicate that mercury levels are lower than the threshold level for reproductive and behavioral harm (5 mg/kg).
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Mercurio , Estrigiformes , Animales , Mercurio/análisis , Plomo , Humedales , Irán , Monitoreo del Ambiente/métodos , Plumas/químicaRESUMEN
The urbanization processes with growing vehicle numbers cause heavy metal pollution in street dust, and high populations in metropolitan cities are exposed to pollutants. This paper aims to monitor the spatial distribution of heavy metals and evaluate the concentrations via health risk assessment of HMs (Cu, Ni, Cd, Co, Pb, and Zn) that expose the inhabitants to health hazards. According to the results of the current study, sixty street dust samples were applied to the acid digestion technique and quantification by inductively coupled plasma-mass spectrometry (ICP-MS). The spatial distribution of the selected heavy metals in the street dust was investigated using the spatial analysis tool in ArcGIS 10.0 according to population density and land use. In the present study, we used hazard index and cancer risk methods to estimate the public health risk of the pollutants exposed to street dust in Ankara. The concentrations range of the elements in street dust over the study area ranged from 3.34-4.50, 31.69-42.87, 16.09-21.54, 42.85-57.55, 0.00-3.51, and 23.03-30.79, respectively. The overall decreasing order of mean concentration of metals was observed as follows: Pb > Cu > Ni > Co > Cd > Zn. Vehicle traffic and industrial activities seem to be the most critical anthropogenic sources responsible for dust pollution in the study area. The risk assessment of Pb and Ni exposure was the highest, and the hazard index values were 2.42E + 00 and 2.28E + 00 mg/kg/day for children. However, the effect on adults was 2.62E-01 and 2.37E-02 mg/kg/day, followed by inhalation and dermal contact with street dust was almost negligible. The decreasing concentration is modeled spatially along the western development corridor of the city. The risk to public health is high in areas with high densities close to the city center and the main artery.
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Cadmio , Contaminantes Ambientales , Adulto , Niño , Humanos , Plomo , Monitoreo del Ambiente , Intoxicación por Metales Pesados , Medición de Riesgo , PolvoRESUMEN
In this study, the pollution and bioavailability of heavy metals in the sediments of Anzali Wetland were measured by analyzing data from sequential chemical extraction of sediments, risk assessment code (RAC), and sediment pollution indices. The average RAC results indicated that the risk from Zn, Cr, Cu, and Hg was low, while the risk from Pb, Ni, As, and Cd was moderate. To identify the sources of heavy metal pollution in the sediments of Anzali Wetland, multivariate statistical techniques such as Pearson correlation analysis, cluster analysis (CA), and principal component analysis (PCA) were employed. The results of the statistical analyses at a high significance level revealed that Zn, Cr, Cu, Pb, Ni, and As were attributed to natural sources. Additionally, the statistical analyses demonstrated that the concentrations of Cd and Hg in the sediments of Anzali Wetland were influenced by non-oil organic sources and atmospheric deposition, respectively.
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Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Humedales , Cadmio/análisis , Plomo/análisis , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Mercurio/análisis , Medición de Riesgo , ChinaRESUMEN
Road-deposited sediments (RDS) on urban impervious surfaces are important carriers of heavy metals (HMs), and can contribute to urban runoff pollution. With the outbreak of COVID-19, chlorinated disinfectants (CDs) have been extensively sprayed on these surfaces. This practice may have a superposed or priming effect on HMs contaminants in RDS, yet this remains unknown. This study examined the effects of seven CDs concentration gradients (0, 250, 500, 1000, 2000, 5000, 60,000 mg/L) on the leaching and chemical forms of HMs (Cd, Cr, Ni, Pb, and Zn) in seven particle size fractions (<44, 44-63, 63-105, 105-149, 149-250, 250-450, 450-1000 µm). The results showed that CDs can promote the leaching of HMs in RDS, at the recommended CDs dose (2000 mg/L), except for Pb, the leaching amounts increased by 21.8%-237.2% compared with the untreated RDS. The alteration in the leaching were primarily attributed to the redistribution of chemical forms of HMs in RDS, specifically, the acid-extractable fractions percentage increased by 0.23%-24.39%, and the reducible fractions percentages decreased by 3.21%-38.35%. The lower oxidation-reduction potential (ORP) and alkalinity of CDs as strong oxidants were responsible for the redistribution of forms. The leaching and chemical forms of HMs vary among different particle sizes, but in any case, finer particle sizes (< 105 µm) still dominate their contribution. The current control measure of street sweeping is ineffective in removing these particles. These findings will facilitate the development of strategies for controlling urban diffuse pollution from RDS during the pandemic. Finally, this study suggests potential directions for future research.
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COVID-19 , Desinfectantes , Metales Pesados , Humanos , Desinfección , Plomo , Sedimentos Geológicos , Metales Pesados/análisis , Monitoreo del Ambiente , ChinaRESUMEN
Functioning of coastal wetland habitats is essential for the ecosystem integrity and sustainability of coastal development that enables human progress along transitional waterways. However, these habitats are continuously being affected by a variety of pollutants including metallic elements. In this study, seasonal variation, pollution status and ecological risks of heavy metals (Cr, Mn, Co, Ni, As, Cu, Zn and Pb) in surface sediment of the several types of coastal wetlands (estuaries, mudflats, sandy beaches, mangroves, and saltmarshes) were detected by using X-ray fluorescence (EDXRF) spectrometry. The results showed that the mean concentration level of metals in the surficial sediment samples followed the order of Cu (84.06 ± 8.60 µg/g) > Zn (51.00 ± 8.97 µg/g) > Mn (38.25 ± 11.34 µg/g) > Cr (3.52 ± 0.91 µg/g) > Pb (0.27 ± 0.13 µg/g) > Co (0.24 ± 0.13 µg/g) > As (0.21 ± 0.12 µg/g) > Ni (0.16 ± 0.08 µg/g). In comparison to the pre-monsoon period, the post-monsoon season had higher concentrations of heavy metals while the overall accumulation level of metals in the wetlands exhibited a pattern of estuarine wetland (28.47 ± 31.35 µg/g) > mangrove (22.23 ± 30.79 µg/g) > mudflat (21.79 ± 29.71 µg/g) > sandy beach (21.47 ± 28.15 µg/g) > saltmarsh (21.28 ± 30.02 µg/g). Although, the pollution assessment indices e.g., contamination factor (CF), degree of contamination (CD), geoaccumulation index (Igeo) and pollution load index (PLI) showed minimal levels of contamination in the studied sites, enrichment factor (EF) suggested greater enrichment of the metals in the pre-monsoon season but with the lowest ecological risk (RI < 40) in both seasons. Cluster analysis, principal component analysis (PCA), and Pearson's correlation were performed to determine the sources of heavy metals in collected samples which specified that Pb, As, Co and Ni predominantly came from natural sources whereas Cu, Mn, Zn and Cr emerged from anthropogenic sources such as industrial effluents, domestic wastewater, fertilizer or pesticide consumption on farmland along the riverbank, vessel emissions, and the confluence of tributary rivers.
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Metales Pesados , Contaminantes Químicos del Agua , Humanos , Estaciones del Año , Humedales , Ecosistema , Bahías , Plomo/análisis , Sedimentos Geológicos/química , Metales Pesados/análisis , Medición de Riesgo , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisisRESUMEN
The coronavirus disease 2019 (COVID-19) pandemic has not only brought considerable and permanent changes to economies and healthcare systems, but it has also greatly changed the habits of almost the entire society. During the lockdowns, people were forced to stay in their dwellings, which served as a catalyst for the initiation of a survey on the estimation of the metallic element content in residential indoor dust in different parts of Latvia. This article presents the study results obtained through the analysis of collected dust samples from 46 dwellings, both in the capital of Latvia, Riga, and in smaller cities. Two methods were employed for indoor dust collection: vacuum sampling and manual sampling with a brush and plastic spatula. After microwave-assisted acid extraction, the samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) in terms of the major (Na, K, Ca, Mg, Al and Fe) and minor (Mn, Ni, Co, Pb, Cr, As, Ba, Li, Be, B, V, Cu, Zn, Se, Rb, Sr, Cd, La, Ce and Bi) elements. For the data analysis, principal component analysis was performed. Among the measured metals, the highest values were determined for the macro and most abundant elements (Na > K > Ca > Fe > Mg > Al). The concentration ranges of the persistently detected elements were as follows: Pb, 0.27-1200 mg kg-1; Cd, 0.01-6.37 mg kg-1; Ni, 0.07-513 mg kg-1; As, 0.01-69.2 mg kg-1; Cu, 5.71-1900 mg kg-1; Zn, 53.6-21,100 mg kg-1; and Cr, 4.93-412 mg kg-1. The critical limit values of metallic elements in soil defined by the legislation of the Republic of Latvia (indicating the level at or above which the functional characteristics of soil are disrupted, or pollution poses a direct threat to human health or the environment) were exceeded in the following numbers of dwellings: Pb = 4, Ni = 2, As = 1, Cu = 16, Cr = 1 and Zn = 28.
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COVID-19 , Metales Pesados , Oligoelementos , Humanos , Polvo/análisis , Letonia , Cadmio/análisis , Plomo/análisis , Control de Enfermedades Transmisibles , Suelo/química , Monitoreo del Ambiente , Metales Pesados/análisis , Oligoelementos/análisisRESUMEN
Atmospheric particulate matter (PM) enriched with lead (Pb) has severe irreversible effects on human health. Therefore, identifying the contribution of Pb emission sources is essential for protecting the health of residents. Using the Pb isotopic tracer method, this study explored the seasonal characteristics and primary anthropogenic Pb sources for atmospheric PM in Tianjin in 2019. We calculated the contribution of Pb sources using the end-member and MixSIAR models. The results showed that Pb loaded in PM10 was more abundant in January than in July, and was strongly influenced by meteorological conditions and anthropogenic emissions. The primary Pb sources of the aerosol samples originated from coal combustion and vehicle and steel plant emissions, mainly originating from local Pb emission sources in Tianjin. The PM10-bond Pb in January was influenced by regional transportation and local sources. The MixSIAS model calculated the contribution of coal combustion as approximately 50 %. Compared with that in January, the contribution of coal combustion decreased by 9.6 % in July. Our results indicate that some of the benefits of phased-out leaded gasoline have been short-lived, whereas other industrial activities releasing Pb have increased. Furthermore, the results emphasise the practicability of the Pb isotope tracer source approach for identifying and distinguishing between different anthropogenic Pb inputs. Based on this study, scientific and effective air pollution prevention and control programs can be formulated to provide decision support for the guidance and control of air pollutant emissions.
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Contaminantes Atmosféricos , Plomo , Humanos , Plomo/análisis , Teorema de Bayes , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Isótopos/análisis , Carbón Mineral/análisis , Monitoreo del Ambiente/métodos , ChinaRESUMEN
BACKGROUND: Lead is a major developmental neurotoxicant in children, and tobacco smoke has been suggested as a source of lead exposure in vulnerable populations. This study evaluates the contribution of secondhand tobacco smoke (SHS) to blood lead levels (BLLs) in children and adolescents. METHODS: We analyze data from 2,815 participants aged 6-19 years who participated in the National Health and Nutrition Examination Survey (2015-2018) to investigate the association between serum cotinine levels and BLLs. A multivariate linear regression was conducted to estimate geometric means (GMs) and the ratios of GMs after adjusting for all covariates. RESULTS: The geometric means of BLLs in study participants aged 6 - 19 years were 0.46 µg/dl (95% CI 0.44, 0.49). After adjusting for relevant participant characteristics, the geometric means of BLLs were 18% (BLL 0.48 µg/dl, 95% CI 0.45, 0.51) and 29% (BLL 0.52 µg/dl, 95% CI 0.46, 0.59) higher in participants who had intermediate serum cotinine levels (0.03 - 3 ng/mL) and those who had high serum cotinine levels (> 3 ng/mL) respectively, compared to participants who had low serum cotinine levels (BLL 0.41 µg/dl, 95% CI 0.38, 0.43). CONCLUSIONS: SHS exposure may be a source of BLLs in US children and adolescents. Efforts to reduce lead exposure in children and adolescents should include strategies to reduce SHS exposure.
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Contaminación por Humo de Tabaco , Humanos , Adolescente , Niño , Plomo , Estudios Transversales , Encuestas Nutricionales , CotininaRESUMEN
BACKGROUND: Lead (Pb) and cadmium (Cd) heavy metals are considered potentially hazardous toxins which cause serious health problems. Many studies reported that the water of Qaroun Lake in Fayoum, Egypt with its fish farms was contaminated with Pb and Cd above permissible levels. However, there is a lack of studies addressing levels of these toxic metals among inhabitants. OBJECTIVES: We aimed to evaluate blood levels of Pb and Cd and their potential health risk among inhabitants around Qaroun Lake. MATERIALS AND METHODS: This case-control study estimated Pb and Cd blood levels among 190 individuals from two destinations (near and far away) of Qaroun Lack using an atomic absorption spectrometer after full history taking and routine checkup investigations; Full blood count, serum ferritin, liver enzyme (ALT), and creatinine levels. RESULTS: There was a significant difference between blood levels of Pb and Cd heavy metals of inhabitants from near and far away Qaroun Lake destinations (p-value < 0.001). The majority of inhabitants around Qaroun Lake had Pb and Cd blood levels above permissible levels (100% and 60% respectively). Critical levels out of them were 12.1% and 30.3% respectively. In comparison to inhabitants faraway Qaroun Lake, three individuals (2.4%) had Cd above the permissible level, while all of them (100%) had Pb level within the permissible level. There were no statistically significant differences between the two sampled populations as regards hemoglobin level, ALT, creatinine, and ferritin serum levels (p-value > 0.05). The difference between studied populations regarding types of anemia was not statistically significant. Subclinical leucopenia was higher in the population near Qaroun Lake when compare to inhabitants far from the lake (13.6% vs. 4.8%, p-value 0.032). CONCLUSION: Bio-monitoring of populations exposed to Pb and Cd hazardous substances could help in generating an early warning system to reduce the disease burden associated with their toxicity.
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Metales Pesados , Contaminantes Químicos del Agua , Humanos , Cadmio/metabolismo , Plomo , Egipto/epidemiología , Lagos , Estudios de Casos y Controles , Creatinina , Metales Pesados/análisis , Ferritinas , Monitoreo del Ambiente , Medición de Riesgo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisisRESUMEN
The objective of this study was to evaluate the effects of high levels of maternal exposure to ambient air pollution and heavy metals on risks of autism spectrum disorder (ASD) and epilepsy using the National Health Insurance claims data of South Korea. The data of mothers and their newborns from 2016 to 2018 provided by the National Health Insurance Service were used (n = 843,134). Data on exposure to ambient air pollutants (PM2.5, CO, SO2, NO2, and O3) and heavy metals (Pb, Cd, Cr, Cu, Mn, Fe, Ni, and As) during pregnancy were matched based on the mother's National Health Insurance registration area. SO2 (OR: 2.723, 95% CI: 1.971-3.761) and Pb (OR: 1.063, 95% CI: 1.019-1.11) were more closely associated with the incidence of ASD when infants were exposed to them in the third trimester of pregnancy. Pb (OR: 1.109, 95% CI: 1.043-1.179) in the first trimester of pregnancy and Cd (OR: 2.193, 95% CI: 1.074-4.477) in the third trimester of pregnancy were associated with the incidence of epilepsy. Thus, exposure to SO2, NO2, and Pb during pregnancy could affect the development of a neurologic disorder based on the timing of exposure, suggesting a relationship with fetal development. However, further research is needed.
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Contaminantes Atmosféricos , Contaminación del Aire , Trastorno del Espectro Autista , Enfermedades del Sistema Nervioso , Embarazo , Lactante , Femenino , Humanos , Recién Nacido , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Exposición Materna/efectos adversos , Trastorno del Espectro Autista/etiología , Dióxido de Nitrógeno/efectos adversos , Dióxido de Nitrógeno/análisis , Cadmio , Plomo , Contaminación del Aire/efectos adversos , Material ParticuladoRESUMEN
In order to understand the pollution status and trophic transfer of heavy metals across wetland food web organisms, four invertebrate species, six fish species, one snake species, and one bird species were collected from an abandoned e-waste site in South China for analysis of toxic elements (Ni, Zn, Cu, Cr, Cd, and Pb). The concentrations of Ni, Zn, Cu, Cr, Cd, and Pb were 0.16-15.6, 24.9-850, 1.49-645, 0.11-64.6, 0.01-4.53 and 0.41-40.4 mg/kg dry weight, respectively. The results demonstrated that the concentrations of six studied heavy metals decreased throughout the whole food web, but Cu and Zn concentrations increased along the bird and reptile food chains, respectively. The trophic transfer of metals for the key species should be of special attention, as the trophic biomagnification factor (TMF) in a food web may overlook the ecological risks of metals for certain species, especially those at high trophic levels. The estimated daily intake (EDI) and the target hazard quotient (THQ) results showed that Cu, Cd, and Pb posed the main risks on human health, especially through the consumption of snail and crab species.
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Residuos Electrónicos , Metales Pesados , Contaminantes Químicos del Agua , Animales , Humanos , Cadena Alimentaria , Cadmio/análisis , Humedales , Residuos Electrónicos/análisis , Plomo/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , China , Medición de Riesgo , Contaminantes Químicos del Agua/análisisRESUMEN
The main aim of this study is modeling of a continuous biosorption system for the removal of Pb(II) ions in the aqueous conditions using live Dunaliella salina microalgae. The live microalgae can grow in saline water and opens new opportunities in varying the amount and properties of biosorbent. The effects of five parameters, including pH, optical density of algae as a factor indicating the adsorbent dosage, injection time, contact time, and initial concentration of Pb(II), were optimized by means of response surface methodology (RSM) based on the central composite design (CCD). Dunaliella salina algae showed maximum Pb(II) biosorption with 96% efficiency. For the selective Pb(II) uptake in the presence of Cd(II) and Ni(II), binary and ternary systems of ions were chosen. The mutual effect of each heavy metal ion in all systems on the total uptake percentage was also examined. The ion selectivity was investigated in the presence of diverse heavy metal ions, and the Pb(II) uptake percentage was determined to be 80%. Both Langmuir and Freundlich isotherm models were suitable for describing multicomponent binary and ternary systems depending on the presence of competitive ions in the mixture. Main functional groups and surface properties of the Dunaliella salina were identified by Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive spectrometry. Hence, effective heavy metal ion uptake, simple design, and cost-effective cultivation confirmed live Dunaliella salina as suitable microalgae for purifying contaminated water in an economic and safe manner.
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Metales Pesados , Contaminantes Químicos del Agua , Plomo/análisis , Monitoreo del Ambiente , Metales Pesados/análisis , Plantas , Iones/análisis , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisisRESUMEN
Wetland is an important feature of the landscape that provides beneficial services. However, with the ever-increasing heavy metal load, the quality of wetlands is deteriorating. Dongzhangwu Wetland in Hebei, China, was taken as our study site. It provides breeding and foraging grounds to migratory water birds such as Little Egret (Egretta garzetta), Great Egret (Ardea alba), and Grey Heron (Ardea cinerea). The current study aimed to quantify heavy metals exposure hazard and risk to the water migratory birds by employing a non-destructive approach. Oral intake was considered the main exposure route to calculate total exposure via multiple phases. The concentrations of Cr, Zn, Cu, Pb, As, Ni, Mn, and Cd were investigated in water, soil and food compartments of three different habitat components (Longhe River, Natural Pond and Fish Pond). The results showed: (1) The trend of potential daily dose (PDD) was Mn > Zn > Cr > Pb > Ni > Cu > As > Cd while for hazard quotient (HQ) was Cr > Pb > Cu > Zn > As > Ni > Mn > Cd, making Cr, Pb, Cu, Zn, and As the priority pollutants in all habitats, with Natural Pond eliciting the highest exposure. (2) The cumulative heavy metal exposure, explained by the integrated nemerow risk index, characterized all three habitats for all the birds in high exposure risk category. (3) The exposure frequency index identified that all the birds are frequently exposed to heavy metals from multiple phases in all three habitats. (4) Little Egret is at the highest pedagogy of exposure from single or multiple heavy metal(s) in all three habitats. A rigorous management plan for identified priority pollutants is required to improve wetland functioning and ecological services. Decision-makers could use the developed tissue residue objectives for protecting Egret species in Dongzhangwu Wetland as benchmarks.
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Contaminantes Ambientales , Metales Pesados , Contaminantes Químicos del Agua , Animales , Ecosistema , Humedales , Monitoreo del Ambiente/métodos , Cadmio , Plomo , Metales Pesados/análisis , Aves , Medición de Riesgo , China , Contaminantes Químicos del Agua/análisisRESUMEN
This study was aimed to describe the chemical traces of air pollution in blood of residents and evaluate the association between ambient pollution and its dose absorbed internally by a human body. The national Magen David Adom Blood Services blood donation collection platform and the National Public Health Laboratory's testing services were utilized to conduct a human biomonitoring study among blood donors in Israel. The donors' residential addresses and donations sites' locations were geocoded and merged with the levels of pollutants recorded by the nearby monitoring stations. Pollutants included nitrogen dioxide (NO2), sulfate dioxide (SO2), ozone (O3), carbon monoxide (CO) and particulate matter of size <10 and 2.5 µm in diameter (PM10 & PM2.5). Metal concentrations were statistically analyzed by ratio t-test and a lognormal regression, and adjusted to age, gender and smoking (defined based on Cadmium values). The findings indicate an independent positive association between pollutants and metals' concentrations in blood. Specifically, an increase in interquartile range (IQR) of NO2 was associated with 9.5 % increase in As in blood. The increase in one IQR of PM10 and SO2 was associated with an increase in Pb, of 16.6 % and 12.4 %, respectively. SO2 was also adversely associated with Cd concentrations, by increasing its levels by 5.7 %. The donors' proximity to quarries was related to the Pb blood levels higher 1.47 times compared to donors without quarries close to their residence (p-value = 0.013). To conclude, ambient pollution levels are associated with internal metals' concentrations, reaffirming the link between the two in the pathological pathway from air pollution to morbidity.
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Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Ambientales , Ozono , Humanos , Contaminantes Atmosféricos/análisis , Dióxido de Nitrógeno/análisis , Almacenamiento de Sangre , Plomo , Contaminación del Aire/análisis , Material Particulado/análisis , Ozono/análisis , Exposición a Riesgos Ambientales/análisis , Dióxido de Azufre/análisisRESUMEN
This study aimed to analyze the temporal trends, pollution levels, and health risks associated with eleven PM2.5-bound heavy metals (Sb, Al, As, Hg, Cd, Cr, Mn, Ni, Pb, Se and Tl). A total of 504 PM2.5 samples were collected in Suzhou from January 2019 to December 2021. The pollution levels were estimated based on enrichment factors (EFs) which can be used to calculate the enrichment of heavy metals in PM2.5 and determine whether the concentrations of PM2.5-bound heavy metals are influenced by the crustal or anthropogenic sources, and the health risk of PM2.5-bound heavy metals via inhalation was assessed following US EPA's Risk Assessment Guidance for Superfund (RAGS). The annual average concentration of PM2.5 was 46.76 µg m-3, which was higher than the WHO recommended limit of 5 µg m-3. The average of the sum of eleven PM2.5-bound heavy metals was 180.61 ng m-3, dominated by Al, Mn, and Pb. The concentration of PM2.5 in 2020 was significantly lower than that in 2019 and 2021. The PM2.5 and PM2.5-bound heavy metal concentrations in winter and spring were significantly higher than those in autumn and summer. The EF of As, Cr, Cd, Hg, Ni, Pb, Sb, Mn, Se, and Tl was higher than 10, indicating they were mainly from anthropogenic sources. Exposure to a single non-carcinogenic heavy metal via inhalation was unlikely to cause non-carcinogenic effects (HQ < 1), but the integrated non-carcinogenic risks should be taken seriously (HI > 1). The cumulative carcinogenic risks from the carcinogenic elements were exceeding the lower limit (1 × 10-6) of the acceptable risk range. The carcinogenic risks of As and Cr(VI) contributed 60.98% and 26.77%, respectively, which were regarded as two key carcinogenic risk factors. Overall, the government policies and countermeasures for the PM2.5 pollution control should be performed not only based on the PM2.5 concentration but also based on the PM2.5-bound heavy metals and their health risks for the local residents.
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Mercurio , Metales Pesados , Humanos , Material Particulado/toxicidad , Material Particulado/análisis , Cadmio , Plomo , Monitoreo del Ambiente , Metales Pesados/toxicidad , Metales Pesados/análisis , Medición de Riesgo , ChinaRESUMEN
Lead (Pb) is a neurotoxic metal, and no level of lead exposure is safe for children. China has still experienced problems on child lead poisoning even though the Chinese government has phased out leaded gasoline since 2000. The underlying problem affecting the lead pollution-related health of children in China remains to be comprehensively investigated. It is found that although the significant decline of BLLs, as the Geometric Mean (GM), from 91.40 µg/LGM in 2001 to 37.52 µg/LGM in 2018 is observed, the average BLLs of children are still above 50 µg/L or more [average 59.70 (60.50-65.02, 95 % CI) µg/LGM] after phasing out leaded gasoline since 2000 in China. Lead exposure causes 29.67 MID per 1000 children with a loss of 98.23 (59.40-146.21, 95 % CI) DALYs per 1000 in China, which is greater than the levels reported from the Western Pacific Region and other low- and middle-income countries. A significant correlation is observed between the number of child crimes (NoCCs) and the outcomes of long-term lead exposure for children in China. Although the disparities in BLLs in China are strongly influenced by unequal distributions of potential multi-lead related sources (soil lead, PM2.5 lead, dust lead), unbalance development of local industrialization and economies, as well as incorrect health care for younger children, the notable emissions from coal combustion (CC) and non-ferrous metals (NMS) exploitation dominate the crucial sources of low-level lead exposure to children after phasing out leaded gasoline in China currently. Faced with the unequal and disparate distribution of BLLs in China, the big bottleneck is to decrease the BLLs exertions of 36-45 µg/L in the next few decades. The Chinese government needs to make more efforts on developing more strict guidelines, implementing more policy strategies on prevention and management of blood Pb poisoning, and monitoring the nationwide changes in children's BLLs continuously.
Asunto(s)
Intoxicación por Plomo , Plomo , Humanos , Niño , Exposición a Riesgos Ambientales , Gasolina , Contaminación Ambiental , Intoxicación por Plomo/epidemiología , Intoxicación por Plomo/etiología , China/epidemiologíaRESUMEN
This study was performed to evaluate the impact of microplastics and heavy metals (Pb, Cd, Cr, Cu, Zn, Ni) on sediments, water, aquatic plants (Pistia stratiotes, Alternanthera philoxeroides, and Ipomoea carnea), and fish (Labeo rohita) samples collected from five different sites in the Bajwat wetlands in Sialkot, Pakistan. The concentrations of Pb, Cd, and Cr were above the permissible limits devised by WHO in all the ecosystem components (i.e. sediments, water, plants, and fish) at all sites. The maximum amount of microplastic particles (2317 microplastic particles per kg of sediments) was recorded at Site 1. The filaments were the most commonly found type of microplastics. Plants and fish samples also showed considerable concentration of metals. The multivariate statistical analysis revealed anthropogenic sources of elevated concentrations of metal elements which could cause adverse biological effects in the ecosystem.
