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Evaluating levels and health risk of heavy metals in exposed workers from surgical instrument manufacturing industries of Sialkot, Pakistan
2016
Junaid, Muhammad | Hashmi, Muhammad Zaffar | Malik, Riffat Naseem
The study aimed to monitor heavy metal (chromium, Cr; cadmium, Cd; nickel, Ni; copper, Cu; lead, Pb; iron, Fe; manganese, Mn; and zinc, Zn) footprints in biological matrices (urine, whole blood, saliva, and hair), as well as in indoor industrial dust samples, and their toxic effects on oxidative stress and health risks in exposed workers. Overall, blood, urine, and saliva samples exhibited significantly higher concentrations of toxic metals in exposed workers (Cr; blood 16.30 μg/L, urine 58.15 μg/L, saliva 5.28 μg/L) than the control samples (Cr; blood 5.48 μg/L, urine 4.47 μg/L, saliva 2.46 μg/L). Indoor industrial dust samples also reported to have elevated heavy metal concentrations, as an example, Cr quantified with concentration of 299 mg/kg of dust, i.e., more than twice the level of Cr in household dust (136 mg/kg). Superoxide dismutase (SOD) level presented significant positive correlation (p ≤ 0.01) with Cr, Zn, and Cd (Cr > Zn > Cd) which is an indication of heavy metal’s associated raised oxidative stress in exposed workers. Elevated average daily intake (ADI) of heavy metals resulted in cumulative hazard quotient (HQ) range of 2.97–18.88 in workers of different surgical units; this is an alarming situation of health risk implications. Principal component analysis-multiple linear regression (PCA-MLR)-based pie charts represent that polishing and cutting sections exhibited highest metal inputs to the biological and environmental matrices than other sources. Heavy metal concentrations in biological matrices and dust samples showed a significant positive correlation between Cr in dust, urine, and saliva samples. Current study will help to generate comprehensive base line data of heavy metal status in biomatrices and dust from scientifically ignored industrial sector. Our findings can play vital role for health departments and industrial environmental management system (EMS) authorities in policy making and implementation.
显示更多 [+] 显示较少 [-]Effect of dimethyl phthalate (DMP) on germination, antioxidant system, and chloroplast ultrastructure in Cucumis sativus L
2016
Zhang, Ying | Zhang, Hui | Sun, Xin | Wang, Lei | Du, Na | Tao, Yue | Sun, Guoqiang | Erinle, Kehinde O. | Wang, Pengjie | Zhou, Changjian | Duan, Shuwei
Pollution of agricultural soils caused by widely employed plastic products, such as phthalic acid esters (PAEs), are becoming widespread in China, and they have become a threat to human health and the environment. However, little information is available on the influence of PAEs on vegetable crops. In this study, effects of different dimethyl phthalate (DMP) treatments (0, 30, 50, 100, and 200 mg L⁻¹) on seed germination and growth of cucumber seedlings were investigated. Although germination rate showed no significant difference compared to control, seed germination time was significantly delayed at DMP greater than 50 mg L⁻¹. Concentrations of DMP greater than 30 mg L⁻¹ reduced cucumber lateral root length and number. The measurement of five physiological indexes in cucumber leaves with increasing DMP concentration revealed a decrease in leaf chlorophyll content, while proline and H₂O₂ contents increased. Peroxidase (POD) and catalase (CAT) activities increased in cucumber plants under 30 and 50 mg L⁻¹ DMP treatments compared to control; while after a 7-day treatment, these activities were seriously reduced under 100 and 200 mg L⁻¹ DMP treatments. According to transmission electron microscopy (TEM) micrographic images, the control and 30 mg L⁻¹ DMP treatments caused no change to leaf chloroplast shape with well-structured thylakoid membrane and parallel pattern of lamellae. At concentrations higher than 30 mg L⁻¹, DMP altered the ultrastructure of chloroplast, damaged membrane structure, disordered the lamellae, and increased the number and volume of starch grains. Moreover, the envelope of starch grains began to degrade under 200 mg L⁻¹ DMP treatment.
显示更多 [+] 显示较少 [-]Sorption of selected pharmaceuticals and pesticides on different river sediments
2016
Radović, Tanja T. | Grujić, Svetlana D. | Kovačević, Srđan R. | Laušević, Mila D. | Dimkić, Milan A.
In the present work, the sorption ability of 17 pharmaceutical compounds, two metabolites, and 15 pesticides (34 target compounds in total) onto four different river sediments was investigated separately. Selected compounds present the most frequently prescribed pharmaceuticals in human and animal medicine and the most frequently used pesticides in agriculture. Their presence into the surface, ground, and waste waters was confirmed into the numerous papers in literature, as well as their presence into the river sediments (for some of them). However, investigations of their sorption onto the river sediments, as major natural protection from potential pollution of ground water by them is missing. Sorption in this study was investigated onto river sediments taken from rivers in the Republic of Serbia, where only less than 10 % of total generated waste water passes through mainly basic treatment processes. Experiments were based on batch equilibrium procedures and obtained solutions were analyzed by previously developed and validated sensitive high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) analytical methods. All results were modeled by Freundlich isotherms. Obtained results have shown that Kf coefficient values are in correlation with organic carbon content. Kd sorption coefficient values were relatively low and ranged in wide ranges for almost all compounds and sediments. That implicates on the conclusion that capacities of the investigated sorbents are not large for those compounds.
显示更多 [+] 显示较少 [-]A review of the Texas, USA San Jacinto Superfund site and the deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in the San Jacinto River and Houston Ship Channel
2016
Iyer, Rupa | Aggarwal, Juhi | Iken, Brian
The San Jacinto River (SJR) waste pits that lie just under the 1–10 overpass in eastern Harris County east of Houston, Texas, USA, were created in the 1960s as dumping grounds for paper mill waste. The deposition of this waste led to accumulation of highly toxic polychlorinated dibenzo-p-dioxins and dibenzofurans (PCCDDs/PCDFs) over the course of several decades. After abandonment, the waste material eventually became submerged under the waters of the SJR, resulting in widespread environmental contamination that currently constitutes a significant health concern for eastern Harris County communities. The original waste pits were rediscovered in 2005, and the San Jacinto waste site is now a designated EPA superfund site. The objective of this review then is to discuss the history and current state of containment around the San Jacinto waste pits and analyze spatial and temporal trends in the PCDD/PCDF deposition through the SJR system from the data available. We will discuss the current exposure and health risks represented by the Superfund site and the SJR system itself, as well as the discovery of liver, kidney, brain (glioma), and retinoblastoma cancer clusters in eastern Harris County across multiple census tracts that border the Superfund site. We will also cover the two primary management options, containment versus removal of the waste from the Superfund and provide recommendations for increased monitoring of existing concentrations of polychlorinated waste in the SJR and its nearby associated communities.
显示更多 [+] 显示较少 [-]Effect of thermal pre-treatment on the availability of PAHs for successive chemical oxidation in contaminated soils
2016
Usman, M. | Chaudhary, A. | Biache, C. | Faure, P. | Hanna K.,
This is the premier study designed to evaluate the impact of thermal pre-treatment on the availability of polycyclic aromatic hydrocarbons (PAHs) for successive removal by chemical oxidation. Experiments were conducted in two soils having different PAH distribution originating from former coking plant sites (Homécourt, H, and Neuves Maisons, NM) located in northeast of France. Soil samples were pre-heated at 60, 100, and 150 °C for 1 week under inert atmosphere (N₂). Pre-heating resulted in slight removal of PAHs (<10 %) and loss of extractable organic matter (EOM). Then, these pre-heated soil samples were subjected to Fenton-like oxidation (H₂O₂ and magnetite) at room temperature. Chemical oxidation in soil without any pre-treatment showed almost no PAH degradation underscoring the unavailability of PAHs. However, chemical oxidation in pre-heated soils showed significant PAH degradation (19, 29, and 43 % in NM soil and 31, 36, and 47 % in H soil pre-treated at 60, 100, and 150 °C, respectively). No preferential removal of PAHs was observed after chemical oxidation in both soils. These results indicated the significant impact of pre-heating temperature on the availability of PAHs in contaminated soils and therefore may have strong implications in the remediation of contaminated soils especially where pollutant availability is a limiting factor.
显示更多 [+] 显示较少 [-]Ecological implication of variation in the secondary metabolites in Parmelioid lichens with respect to altitude
2016
Shukla, Vertika | Patel, D. K. | Bajpai, Rajesh | Semwal, Manoj | Upreti, D. K.
Lichens are known to synthesize a variety of secondary metabolites having multifunctional activity in response to external environmental condition. Two common lichen extrolites, atranorin and salazinic acid, are known to afford antioxidant as well as photoprotectant nature depending on the abiotic/biotic stress. The present investigation aims to study the influence of altitudinal gradient on the quantitative profile of atranorin and salazinic acid in three lichen species, Bulbothrix setschwanensis (Zahlbr.) Hale, Everniastrum cirrhatum (Fr.) Hale and Parmotrema reticulatum (Taylor) Choisy, Parmeliaceae using liquid chromatography-mass spectrometry (LC-MS/MS) technique. Samples were collected from high-altitude area, usually considered as non-polluted sites of Garhwal Himalaya. Characterization and quantification of the lichen substances in samples were carried out comparing with the standards of atranorin and salazinic acid. Results indicated significant variation in the chemical content with the rising altitude. All the three lichen species showed higher quantities of chemical substances with the altitudinal rise, while among the three lichen species, E. cirrhatum showed the highest quantity of total lichen compounds. The higher abundance and frequency of E. cirrhatum with increasing altitude as compared to B. setschwanensis and P. reticulatum may be attributed due to the presence of higher quantity of photoprotecting/antioxidant chemicals especially salazinic acid. Thus, the present study shows the prominent role of secondary metabolite in wider ecological distribution of Parmelioid lichens at higher altitudes.
显示更多 [+] 显示较少 [-]Evaluation of coexposure to inorganic arsenic and titanium dioxide nanoparticles in the marine shrimp Litopenaeus vannamei
2016
Cordeiro, Lucas | Müller, Larissa | Gelesky, Marcos A. | Wasielesky, Wilson | Fattorini, Daniele | Regoli, Francesco | Monserrat, José Marìa | Ventura-Lima, Juliane
The acute toxicity of titanium dioxide nanoparticles (nTiO₂) that occur concomitantly in the aquatic environment with other contaminants such as arsenic (As) is little known in crustaceans. The objective of the present study is to evaluate whether coexposure to nTiO₂ can influence the accumulation, metabolism, and oxidative stress parameters induced by arsenic exposure in the gills and hepatopancreas of the shrimp Litopenaeus vannamei. Organisms were exposed by dissolving chemicals in seawater (salinity = 30) at nominal concentrations of 10 μg/L nTiO₂ or Asᴵᴵᴵ, dosed alone and in combination. Results showed that there was not a significant accumulation of As in either tissue type, but the coexposure altered the pattern of the metabolism. In the hepatopancreas, no changes were observed in the biochemical response, while in the gills, an increase in the glutamate-cysteine-ligase (GCL) activity was observed upon exposure to As or nTiO₂ alone, an increase in the reduced glutathione (GSH) levels was observed upon exposure to As alone, and an increase in the total antioxidant capacity was observed upon exposure to nTiO₂ or nTiO₂ + As. However, these modulations were not sufficient enough to prevent the lipid damage induced by nTiO₂ exposure. Our results suggest that coexposure to nTiO₂ and As does not alter the toxicity of this metalloid in the gills and hepatopancreas of L. vannamei but does alter its metabolism, favoring its accumulation of organic As species considered moderately toxic.
显示更多 [+] 显示较少 [-]Additional disturbances as a beneficial tool for restoration of post-mining sites: a multi-taxa approach
2016
Řehounková, Klára | Čížek, Lukáš | Řehounek, Jiří | Šebelíková, Lenka | Tropek, Robert | Lencová, Kamila | Bogusch, Petr | Marhoul, Pavel | Máca, Jan
Open interior sands represent a highly threatened habitat in Europe. In recent times, their associated organisms have often found secondary refuges outside their natural habitats, mainly in sand pits. We investigated the effects of different restoration approaches, i.e. spontaneous succession without additional disturbances, spontaneous succession with additional disturbances caused by recreational activities, and forestry reclamation, on the diversity and conservation values of spiders, beetles, flies, bees and wasps, orthopterans and vascular plants in a large sand pit in the Czech Republic, Central Europe. Out of 406 species recorded in total, 112 were classified as open sand specialists and 71 as threatened. The sites restored through spontaneous succession with additional disturbances hosted the largest proportion of open sand specialists and threatened species. The forestry reclamations, in contrast, hosted few such species. The sites with spontaneous succession without disturbances represent a transition between these two approaches. While restoration through spontaneous succession favours biodiversity in contrast to forestry reclamation, additional disturbances are necessary to maintain early successional habitats essential for threatened species and open sand specialists. Therefore, recreational activities seem to be an economically efficient restoration tool that will also benefit biodiversity in sand pits.
显示更多 [+] 显示较少 [-]Adsorption behaviors of fungicide-derived copper onto various size fractions of aggregates from orchard soil
2016
Wang, Quan-Ying | Hu, Bo | Yu, Hong-Wen
Although the gradual accumulations of Cu in orchard soils due to the application of Cu-based fungicides have been widely reported, limited information is available about the retention characteristics of fungicide-derived Cu in soil, especially in various size soil aggregates. This study described the adsorption characteristics of Cu from commonly used fungicide, Bordeaux mixture (CuSO₄ + Ca(OH)₂), onto various aggregate fractions (2000–1000, 1000–500, 500–250, 250–106, and <106 μm) of orchard soil. The Cu(NO₃)₂ was selected as a comparison. Two different types of adsorption experiments were conducted as follows: variable pH and variable Cu concentration experiments. The adsorption processes of Bordeaux mixture and Cu(NO₃)₂ onto the studied soil samples followed well with the Freundlich isotherm, and the adsorption isotherms were the S shaped. The adsorption amounts of Cu from different Cu compounds differed, and Bordeaux mixture can result in more Cu retention in soil than Cu(NO₃)₂. The adsorption ability of different size soil aggregates varied, and it was mainly governed by soil properties. The findings of this study suggested that both the chemical compositions of Cu compounds and the soil physical structure should be taken into account when performing soil Cu retention experiments with fungicide-derived Cu.
显示更多 [+] 显示较少 [-]Isolation and characterization of two novel psychrotrophic decabromodiphenyl ether-degrading bacteria from river sediments
2016
Wang, Linqiong | Li, Yi | Zhang, Wenlong | Niu, Lihua | Du, Juan | Cai, Wei | Wang, Jing
Decabromodiphenyl ether (BDE-209) is a brominated flame retardant and a priority contaminant. Currently, little information is available about its significance in the environment, specifically about its susceptibility to aerobic biotransformation at low temperature. In this work, five phylogenetically diverse BDE-209-degrading bacterial strains were isolated from river sediments of northern China. These strains were distributed among four different genera—Acinetobacter, Pseudomonas, Bacillus and Staphylococcus. All five isolates were capable of growing on BDE-209, among which two isolates show better growth. By detailed morphological, physiological, and biochemical characteristics and 16S rDNA sequence analysis, the two strains were identified and named as Staphylococcus haemolyticus LY1 and Bacillus pumilus LY2. The two bacteria can grow in mineral salt medium containing BDE-209 substrate across the temperatures ranging from 2.5 to 35 °C, with an optimum temperature of 25 °C which could be considered as psychrotrophs accordingly. The degradation experiment showed that more than 70.6 and 85.5 % of 0.5 mg/L BDE-209 were degraded and the highest mineralization efficiencies of 29.8 and 39.2 % were achieved for 0.5 mg/L BDE-209 by S. haemolyticus LY1 and B. pumilus LY2, respectively. To the best of our knowledge, this is the first demonstration for the biodegradation of BDE-209 by two psychrotrophic bacteria isolated from environment.
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