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1.
Environ Sci Pollut Res Int ; 30(40): 92817-92829, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37493912

RESUMEN

Globally agrochemicals are widely used in the agricultural sectors, posing potential eco-toxicological risks and disrupting various lifeforms including birds. Thus, the current work was conducted to compare the acute toxic impacts of pesticides (e.g., chlorpyrifos, acetamiprid, and lambda-cyhalothrin) on the pigeon's health. In total 50 adult pigeons were purchased from a local market where these pigeons were fed on pollution-free food. Post adaptation period (15 days), the pigeons were arbitrarily separated into five distinct groups after having been identified in this manner by chance (each group containing 10 pigeons). Control group (group 1) was not treated with any pesticide while the remaining groups (groups 2, 3, and 4) were treated with 0.25-mg/kg body weight of chlorpyrifos, acetamiprid, lambda-cyhalothrin, and a mixture of all three pesticides (group 5), respectively. After 36 days of exposure, the groups that had been exposed to the pesticide showed a significant (p < 0.05) increase in both the total number of platelets and the number of white blood cells (WBCs), in comparison to the control group. On the other hand, the groups that were exposed to the insecticides had significantly lower levels of red blood cells (RBCs), hemoglobin (Hb), and packed cell volume (PCV) (p < 0.05). The value of mean corpuscular volume (MCV) was significantly (p < 0.05) reduced in acetamiprid-exposed group, while a significant increase was observed in other pesticide-exposed groups. Obvious histopathological changes were observed in the tissues of control group and no such changes were reported by control group. Necrosis, pyknosis, lymphocyte infiltration, congestion of blood, dissolution of plasma membrane, and vacuolation were observed in the livers of pesticide-treated pigeons. The intestinal study showed the formation of goblet cells, villi rupturing, degeneration of serosa, necrosis, and pyknosis in treated groups. Renal alterations, dilation of renal tubules, reduction of glomerulus tissue, and edema were observed. This study manifests that the uncontrolled use of pesticides impairs ecosystems and poses a substantial health risk to wildlife and ultimately to human.


Asunto(s)
Cloropirifos , Insecticidas , Plaguicidas , Animales , Humanos , Cloropirifos/toxicidad , Columbidae , Ecosistema , Insecticidas/toxicidad , Plaguicidas/toxicidad , Necrosis
2.
Membranes (Basel) ; 12(10)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36295687

RESUMEN

Finding new biological ways to control biofouling of the membrane in reverse osmosis (RO) is an important substitute for synthetic chemicals in the water industry. Here, the study was focused on the antimicrobial, biofilm formation, and biofilm dispersal potential of rhamnolipids (RLs) (biosurfactants). The MTT assay was also carried out to evaluate the effect of RLs on biofilm viability. Biofilm was qualitatively and quantitatively assessed by crystal violet assay, light microscopy, fluorescence microscopy (bacterial biomass (µm2), surface coverage (%)), and extracellular polymeric substances (EPSs). It was exhibited that RLs can reduce bacterial growth. The higher concentrations (≥100 mg/L) markedly reduced bacterial growth and biofilm formation, while RLs exhibited substantial dispersal effects (89.10% reduction) on preformed biofilms. Further, RLs exhibited 79.24% biomass reduction while polysaccharide was reduced to 60.55 µg/mL (p < 0.05) and protein to 4.67 µg/mL (p < 0.05). Light microscopy revealed biofilm reduction, which was confirmed using fluorescence microscopy. Microscopic images were processed with BioImageL software. It was revealed that biomass surface coverage was reduced to 1.1% at 1000 mg/L of RLs and that 43,245 µm2 of biomass was present for control, while biomass was reduced to 493 µm2 at 1000 mg/L of RLs. Thus, these data suggest that RLs have antimicrobial, biofilm control, and dispersal potential against membrane biofouling.

3.
Chemosphere ; 274: 129811, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33561720

RESUMEN

For the first time, this study presents gaseous and particulate-bound (PM2.5) polycyclic aromatic hydrocarbons (PAHs) in ambient air samples collected from eight major cities of Pakistan. Diurnal air samples (gaseous and PM2.5) were collected in summer 2014 on polyurethane foam and quartz fiber filters using high volume-active air sampler. The US-EPA enlisted 16 priority PAHs in particulate and gaseous phase were measured on gas chromatograph equipped with mass spectrometer detector. The total PAHs concentrations ranged between 188 pg m-3 (in Gilgit), and 2340 pg m-3 (in Lahore). The decreasing order of PAHs concentrations in various cities was in the following order: Lahore > Rawalpindi > Multan > Faisalabad > Karachgi > Peshawar > Quetta > Gilgit. Phenanthrene showed the highest concentration, accounted 18% of total PAHs followed by fluoranthene (12% of total PAHs). This study showed that the gaseous fractions were predominant in the ambient air. Source apportionment analysis revealed that biomass combustion, vehicular emissions and diesel combustion in power generators were the potential PAHs emissions sources. The lifetime lungs cancer risk (LLCR) was in the range of 8.28 × 10-7 to 2.09 × 10-5 depicting mild cancer risk to the residents on exposure to atmospheric PAHs. Therefore, it is recommended to monitor atmospheric PAHs throughout the year and also adopt environmentally friendly fuels to reduce PAHs pollution and health risks in the country.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Ciudades , Monitoreo del Ambiente , Pakistán , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Medición de Riesgo , Estaciones del Año , Emisiones de Vehículos/análisis
4.
Environ Sci Pollut Res Int ; 28(2): 2007-2018, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32862349

RESUMEN

A total of 23 road-dust and 9 house-dust samples were collected from Alexandria and Kafr El-Sheikh cities, Egypt in 2016 to investigate heavy metal (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) contamination, spatial distribution, sources, and health risks. The mean concentrations (mg kg-1) of Cd (road-dust (RD) = 0.33, house-dust (HD) = 0.77), Cu (RD = 80, HD = 141), Pb (RD = 70, HD = 260), and Zn (RD = 169, HD = 771) in Alexandria and Zn (RD = 192, HD = 257) in Kafr El-Sheikh were higher than corresponding background (background refers to generic earth crust shale values given in the literature) levels. Whereas average concentrations (mg kg-1) of Co, Cr, Mn, and Ni (Alexandria: RD = 2.7, 24.3, 251, 14.4; HD = 3.2, 29.2, 237, 25.1 and Kafr El-Sheikh: RD = 6.6, 31.9, 343, 20.2; HD = 8.6, 33.4, 438, 23.2) in both cities were much lower than their background values. Spatially, for most heavy metals, the high concentrations were observed in areas characterized with increased anthropogenic activities, heavy traffic, and high population density. Contamination indices revealed moderate contamination (Cd and Cu) to high contamination (Pb: only house-dust from Alexandria), which posed low (most metals) to moderate ecological risk (Cd and Pb). Correlation analysis and factor analysis classified the studied metals in two groups as: natural input (Co, Cr, Mn, Ni, and Fe) and anthropogenic sources (Cd, Cu, Pb, and Zn). The noncancerous risks posed by studied metals ranged from 0.0001 (Cd) to 0.15 (Pb) and were insignificant. The cancerous risk of Pb (1.4 × 10-4) for children on exposure to house-dust form Alexandria exceeded the guideline values and was considered unacceptable, whereas the cancerous risks of other studied metals were acceptable for both subpopulations. The results of health risk revealed that children are facing higher risk than adults.


Asunto(s)
Polvo , Metales Pesados , Adulto , Niño , China , Ciudades , Polvo/análisis , Egipto , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Medición de Riesgo
5.
Sci Total Environ ; 733: 139349, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32446084

RESUMEN

Hydrogen peroxide (H2O2) is a reactive oxygen species formed in natural water. It is reportedly toxic to aquatic organisms with a predicted no-effect concentration (PNEC) of about 380 nM. In this study, a countrywide investigation of H2O2 concentrations in selected rivers across Japan was conducted to identify rivers that pose toxicity concerns. Twelve rivers with a total catchment area of 13,646 km2 were selected from different prefectures. Spatial and temporal variation studies showed that the H2O2 concentrations (avg. 320 nM, n = 111) varied by two orders of magnitude (range 21-2929 nM) across the rivers. The Yamato River in Osaka and Nara prefectures and the Kokubu River in Chiba Prefecture had the highest concentrations at 276-669 nM and 236-2929 nM, respectively. >75% of the data from the two rivers were either close to or exceeded the PNEC. Most of the results for the other rivers were less than the PNEC. There was a clear seasonal variation in the H2O2 concentrations, with the highest values obtained in summer because of high solar irradiation. The H2O2 concentration had the highest positive correlation (r = 0.61, p < 0.01, n = 111) with the product of dissolved organic carbon and solar radiation intensity, which suggests that these two factors in combination are important in determining the H2O2 concentrations in river water. It was also observed that bigger rivers had lower H2O2 concentration and vice-versa. This shows that the size of a river may influence its H2O2 concentration. This study is the first countrywide survey of H2O2 concentrations in different rivers and evaluation of their relationship with the PNEC. The data provide insight on the factors influencing the concentrations of H2O2 in river water.

6.
Chemosphere ; 218: 517-526, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30500712

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) were analyzed in road and aerial dust to assess their concentration, composition profile, distribution, emission sources, and potential human health risks. Sixteen priority PAHs and Benzo [e]pyrene (BeP) were analyzed in 13 aerial dust samples from Jalalabad, and 78 road dust samples from Kabul and Jalalabad cities, Afghanistan. The mean concentration of ∑17PAHs in road dust from Kabul and Jalalabad were 427  µg kg-1 and 288  µg kg-1, respectively whereas ∑17PAHs in aerial dust from Jalalabad averaged 200  µg kg-1. Fluoranthene (Flu), Chrysene (Chr), Benzo [b]fluoranthene (BbF), Benzo [k]fluoranthene (BkF) and BeP were major individual PAH species. The composition patterns of the PAHs were dominated by 5-6-ring PAHs (51% in road dust from Kabul; 44% in road dust from Jalalabad; and 44% in aerial dust) followed by 4-ring and 2-3-ring PAHs. Source apportionment of the road dust PAHs by the molecular diagnostic ratios (MDR) and principal component analysis (PCA), indicated signatures of PAHs sources (including vehicular exhaust, coal/wood combustion and oil spill). The Benzo [a]pyrene (BaP) toxicity equivalent values (BaPeq17PAHs) for road dust were 75  µg kg-1 (Kabul) and 36 µg kg-1 (Jalalabad); and 35 µg kg-1 for aerial dust (Jalalabad). BaP and Dibenz [a,h]anthracene (DahA) together contributed > 50% of the BaPeq associated cancer risk. All incremental lifetime cancer risk (ILCR) due to human exposure to road and aerial dust PAHs were in the order of 10-7, which is one-fold lower than the threshold (10-6). The noncancerous risk (Hazard Index < 1) on exposure to dust was also negligible for both subpopulations.


Asunto(s)
Contaminantes Atmosféricos/análisis , Polvo/análisis , Exposición a Riesgos Ambientales/efectos adversos , Hidrocarburos Policíclicos Aromáticos/análisis , Afganistán , Ciudades , Carbón Mineral , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Humanos , Neoplasias/inducido químicamente , Contaminación por Petróleo , Medición de Riesgo , Contaminación por Tráfico Vehicular , Madera
7.
Mar Pollut Bull ; 133: 891-899, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30041392

RESUMEN

This study aims to reveal spatial distribution of hydrogen sulfide and sulfur species in marine sediments in Hiroshima Bay, Japan, by direct analyses using a combination of detection tubes and X-ray absorption fine structure spectroscopy. In summer and autumn, the hydrogen sulfide concentration ranged from <0.1 to 4 mg-S L-1. In this study, only hydrogen sulfide was observed in autumn and at two stations in summer. In contrast, some earlier studies reported in all seasons in Hiroshima Bay the presence of acid volatile sulfide, which is used as a proxy of sulfide content. The sulfur species in sediments were mainly identified as sulfate, thiosulfate, elemental sulfur, and pyrite. Thiosulfate was a minor component compared to the other sulfur species. The formation of pyrite and sulfur derived from hydrogen sulfide oxidation played an important role in the scavenging of hydrogen sulfide.


Asunto(s)
Bahías/química , Sedimentos Geológicos/química , Sulfuro de Hidrógeno/análisis , Compuestos de Azufre/química , Japón , Oxidación-Reducción
8.
Arch Environ Contam Toxicol ; 74(1): 32-45, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29159702

RESUMEN

This study was designed to investigate selected road-dust associated heavy metals, their relations with natural and anthropogenic sources, and potential human and environmental health risks. For this purpose, 42 and 36 road-dusts samples were collected from Jalalabad and Kabul cities (Afghanistan), respectively. The following elements were found in descending concentrations: Mn, Zn, Pb, Ni, Cu, Cr, Co, and Cd in Jalalabad; and Mn, Zn, Ni, Cu, Cr, Pb, Co, and Cd in Kabul. Except for Ni, all the elemental contents were less than the Canadian permissible limits in residential/parkland soils. Principle Component Analysis and enrichment of Cd, Cu, Ni, Pb, and Zn pointed to anthropogenic sources, whereas Co, Cr, and Mn indicated crustal inputs. Broadly, Cd monomial risk index ([Formula: see text]) was considerable; however, one site each in both cities showed high risk ([Formula: see text] ≥ 350). The potential ecological risk (RI) is mostly low; however, at some sites, the risk was considerable. Ingestion appeared to be the main exposure route (99%) for heavy metals and contributed > 90% to noncancerous (all residents), as well as 92% (children) and 75-89% (adults) cancerous risks. The noncancerous risks of all metals and their integrated risks for all residents were within acceptable levels. Moreover, potential cancer risks in children from Ni and Cr were slightly higher than the US-EPA safe levels but were within acceptable levels for adults. This study found higher risks to children and therefore recommends proper management and ways to control metals pollution load in these areas to decrease human health and RIs.


Asunto(s)
Polvo/análisis , Metales Pesados/análisis , Metales Pesados/toxicidad , Contaminantes del Suelo/análisis , Adulto , Afganistán , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Carcinógenos/análisis , Carcinógenos/toxicidad , Niño , Ciudades , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Contaminación Ambiental/efectos adversos , Contaminación Ambiental/análisis , Humanos , Análisis Multivariante , Salud Pública , Medición de Riesgo , Contaminantes del Suelo/toxicidad
9.
Environ Geochem Health ; 32(3): 179-91, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19862630

RESUMEN

In this study concentrations of selected metals viz., Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Na, Ni, Pb and Zn in surface soils of Sialkot city known worldwide for tanneries and pharmaceutical industries were measured to assess the status of urban soil pollution and to identify sources of contamination. Hierarchical cluster analysis (HACA) indicated concentrations of Mg and Ca related to parent rock material, Cd, Co, and Pb with traffic related activities, Cr, Cu, Ni and Zn either associated with automobiles activities or industrial pollution and Fe, K and Na related with anthropogenic activities or lithogenous materials. Correlation analyses and principal component analysis based on factor analysis confirmed the results of HACA. Spatial distribution maps exhibited relatively higher concentrations of Cd, Co, Cu, Ni, Pb, Cr and Zn along traffic routes in the city and streams. The results highlighted concentration of Cd, Ni, Cr, Zn, and Pb measured in urban soil exceeded the permissible limit of surface soils and advocated an imperative need for detailed baseline investigations of spatial distribution of heavy metals and other contaminants for the formulation of geochemical database that should be made available to stakeholder involved in monitoring, assessment and conservation of soil contamination for future planning and management of the Sialkot city.


Asunto(s)
Sistemas de Información Geográfica , Residuos Industriales , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Curtiembre , Ciudades , Análisis por Conglomerados , Industria Farmacéutica , Geografía , Análisis Multivariante , Pakistán
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