Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in ...surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6–14000ng/g-dry, <2–1500ng/g-dry, 11–3300ng/g-dry, <5–2900ng/g-dry, and 67–9200ng/g-dry in surface soils, and 4.4–78ng/g-dry, <2–20ng/g-dry, 7.3–38ng/g-dry, 6.0–44ng/g-dry and 100–350ng/g-dry in river sediments. Near the open burning site of e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl)diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of <2–190ng/g-dry, <2–69ng/g-dry, <3–51ng/g-dry and 1.7–67ng/g-dry in surface soils. Open storage and burning of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PFRs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling.
Display omitted
•Open storage and burning of e-waste contributed to emission of FRs.•Types of FRs currently in emission are shifting in response to regulations of PBDEs.•Emerging PFRs were detected in soils and sediments around e-waste recycling area.•Presence of alternatives for PBDEs should be regarded as a risk factor.
This study investigated the feasibility of detecting pesticides using terahertz (THz) spectroscopy in high-density polyethylene and/or wheat flour mixtures. The absorption spectra of seven pesticides ...(dicofol, chlorpyrifos, chlorpyrifos-methyl, daminozide, imidacloprid, diethyldithiocarbamate, and dimethyldithiocarbamate) were measured in the frequency range 0.1 to 3 THz at room temperature. Five of the seven pesticides exhibited specific absorption peaks in the low-energy THz range. The two remaining pesticides had no specific absorption peaks in this frequency range, but they exhibited different frequency-dependent refractive indices. The absorption coefficients of imidacloprid increased with its increasing weight ratio in high-density polyethylene, and the fitted power absorptions and refractive indices using a Maxwell-Garnett effective medium model were comparable to the measured data. Imidacloprid was also identified from its characteristic absorption peaks in wheat flour mixtures, and a linear relationship between the absorption coefficient and the weight ratio was observed. Our results show the potential of detection of selected pesticides in foods, such as wheat flour, using THz spectroscopy.
The study of electrochemical behavior of bioactive molecules has become one of the most rapidly developing scientific fields. Biotechnology and biomedical engineering fields have a vested interest in ...constructing more precise and accurate voltammetric/amperometric biosensors. One rapidly growing area of biosensor design involves incorporation of carbon-based nanomaterials in working electrodes, such as one-dimensional carbon nanotubes, two-dimensional graphene, and graphene oxide. In this review article, we give a brief overview describing the voltammetric techniques and how these techniques are applied in biosensing, as well as the details surrounding important biosensing concepts of sensitivity and limits of detection. Building on these important concepts, we show how the sensitivity and limit of detection can be tuned by including carbon-based nanomaterials in the fabrication of biosensors. The sensing of biomolecules including glucose, dopamine, proteins, enzymes, uric acid, DNA, RNA, and H2O2 traditionally employs enzymes in detection; however, these enzymes denature easily, and as such, enzymeless methods are highly desired. Here we draw an important distinction between enzymeless and enzyme-containing carbon-nanomaterial-based biosensors. The review ends with an outlook of future concepts that can be employed in biosensor fabrication, as well as limitations of already proposed materials and how such sensing can be enhanced. As such, this review can act as a roadmap to guide researchers toward concepts that can be employed in the design of next generation biosensors, while also highlighting the current advancements in the field.
Spatial distribution of potentially toxic metals (PTMs) and their accumulation in mangrove Avicennia officinalis L. were studied along 8 locations in and around Sundarban mangrove wetland, India. ...Among 8 locations, S3 (Chemaguri) and S5 (Ghushighata) showed higher concentration of PTMs (Cd, Cr, Cu, Ni, Pb, Zn) characterized by higher enrichment factors (3.45–10.03), geo-accumulation indices (0.04–1.22), contamination factors (1.14–3.51) and pollution load indices (1.3–1.45) indicating progressive deterioration of estuarine quality and considerable ecotoxicological risk. Metal concentration in A. officinalis leaves showed significant correlation with sediment metals implying elevated level of bioaccumulation. Significant statistical correlation between photosynthetic pigments (Chlorophyll a, Chlorophyll b), antioxidant response (free radical scavenging and reducing ability) and stress enzymatic activity (Peroxidase, Catalase, Super-oxide dismutase) of A. officinalis with increasing metal concentration in the contaminated locations reflects active detoxification mechanism of the plant. The study indicates the potentiality of biomonitoring metal pollution using studied biochemical markers in mangrove habitats.
•Accumulation of potentially toxic metals in sediment and mangrove•S3 & S5 show deteriorating sediment quality with considerable ecotoxicological risk.•Correlation of photosynthetic pigment, antioxidative & stress enzyme activity with toxic metals•Studied biochemical markers can be used to assess metal pollution in mangrove habitat.
The Three Gorges Reservoir, the world's largest hydropower project, has operated stably for more than five years. To understand its water quality status, the nutrient and biochemical indexes, the ...total nitrogen (TN), the total phosphorus (TP), the potassium permanganate index (CODMn), the five-day biochemical oxygen demand (BOD5) and fecal coliform (F. coli), as well as the heavy metals (Cu, Hg, As, Cd, Zn and Pb) of samples collected from 10 sites during the time period of 2008–2013 were studied via using multiple analysis approaches. For each parameter, pictures of the spatial and temporal distributions were presented, and the reasons behind their variation trends were elaborated. Principal component analysis (PCA) was applied to identify the types of pollution. The Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI) was calculated to concisely mark the water quality. In addition, a human health risk assessment of the heavy metals in a representative site was conducted. The results showed that the water quality state in the Three Gorges Reservoir was intricate but stable and acceptable from 2008 to 2013. The TN, TP and Pb were considered to be the key pollution indexes. Enforcements to alleviate industrial and urban pollution, along with ship management, have worked. The decrease in heavy metal concentrations from upstream to downstream was associated with the self-purification of the reservoir. However, rural pollution became worse in those years. Improper agricultural activity was an important reason for this trend. For local residents, drinking water was generally safe, but cancer caused by As and Pb is a potential issue.
Display omitted
•An integrated analysis was conducted, including nutrient, biochemical and heavy metal.•Spatial and temporal patterns of pollution were analyzed.•Causes of water quality variations were elaborated.•Types of pollution were identified and corresponding water quality indexes were presented.•Carcinogenic potential of Pb and As should be concerned based on health risk assessment.
•Explore the green technology innovation efficiency in energy-intensive industries.•A two-stage DEA with shared and additional inputs is used to evaluate efficiency.•Explore the promotion path of ...green technology innovation efficiency with FsQCA.•Green technology innovation efficiency within energy-intensive industries varies.•Multi-factor combinatorial efficiency improvement paths vary by size of enterprise.
Energy-intensive industries are high-energy-consumption and high-pollution industries, and their green technology innovation efficiency deserves in-depth investigation. This paper explores the efficiency of green technology innovation and its combinatorial improvement path in energy-intensive industries from 2005-2015 with a two-stage data envelopment analysis model based on shared and additional input resources and fuzzy-set qualitative comparative analysis. The results indicate that (1) the overall efficiency of green technology innovation in energy-intensive industries as a whole showed a fluctuating upward trend from 2005 to 2015, benefiting from the improvement of technology R&D efficiency and achievement conversion efficiency; (2) there is high industry heterogeneity in the green technology innovation capacity of energy-intensive industries, and the difference in the average efficiency in green technology innovation between the industries with the strongest innovation strength and that with the weakest is as high as 0.615; (3) small-scale enterprises’ strategies should be based on foreign scientific research support or environmental regulations, supplemented by a small amount of industry-university-research cooperation. Large-scale enterprises’ strategies should be based on foreign scientific research support and industry-university-research cooperation, supplemented by appropriate environmental regulations and government investment. This study provides a reference for the formulation of green technology innovation development strategies for energy-intensive industries.
Display omitted
This work examined the sorption potential to wastewater primary- and activated-sludge solids for 34 emerging trace organic chemicals at environmentally relevant concentrations. These compounds ...represent a diverse range of physical and chemical properties, such as hydrophobicity and charge state, and a diverse range of classes, including steroidal hormones, pharmaceutically-active compounds, personal care products, and household chemicals. Solid-water partitioning coefficients (
K
d
) were measured where 19 chemicals did not have previously reported values. Sludge solids were inactivated by a nonchemical lyophilization and dry-heat technique, which provided similar sorption behavior for recalcitrant compounds as compared to fresh activated-sludge. Sorption behavior was similar between primary- and activated-sludge solids from the same plant and between activated-sludge solids from two nitrified processes from different wastewater treatment systems. Positively-charged pharmaceutically-active compounds, amitriptyline, clozapine, verapamil, risperidone, and hydroxyzine, had the highest sorption potential, log
K
d
=
2.8–3.8 as compared to the neutral and negatively-charged chemicals. Sorption potentials correlated with a compound’s hydrophobicity, however the higher sorption potentials observed for positively-charged compounds for a given log
D
ow
indicate additional sorption mechanisms, such as electrostatic interactions, are important for these compounds. Previously published soil-based one-parameter models for predicting sorption from hydrophobicity (log
K
ow
>
2) can be used to predict sorption for emerging nonionic compounds to wastewater sludge solids.
► Wastewater sludge partitioning coefficients were measured for 34 organic chemicals. ► Sorption behavior was similar between three primary- and activated-sludge solids. ► Positively-charged chemicals had the highest sorption potential. ► Sorption correlated with hydrophobicity for neutral and negatively-charged chemicals. ► One-parameter linear models can be used to predict sorption to sludge solids.
Background: There is an ongoing controversy on the benefits of treatment protocols, including dental lasers and photodynamic therapy (PDT). The purpose of this study is to compare the local biologic ...effects of PDT, diode soft laser (DSL) therapy, and conventional deep scaling and root planing (SRP) in residual pockets.
Methods: Thirty‐two individuals were included based on a history of previous treatment for periodontitis and the persistence of sites with probing depths >4 mm and bleeding on probing. Residual pockets were debrided with an ultrasonic device and then randomly assigned either to PDT, DSL, or SRP. Gingival crevicular fluid was collected before treatment, after 14 days, and at 2 and 6 months. Levels of 13 cytokines and nine acute‐phase proteins were measured using a bead‐based multiplexing analysis system.
Results: Treatment with PDT, DSL, or SRP led to significant changes in several cytokines and acute‐phase proteins: Compared with baseline, levels of interleukin‐17, basic fibroblast growth factor, granulocyte colony‐stimulating factor, granulocyte macrophage colony‐stimulating factor, and macrophage inflammatory protein 1‐α were lower 14 days and 2 months after treatment. Except for granulocyte colony‐stimulating factor, these differences remained significant throughout the observation period. The levels of five acute‐phase proteins (α‐2 macroglobulin, haptoglobin, serum amyloid P, procalcitonin, and tissue plasminogen activator) were significantly higher at 6 months than at baseline. No significant differences were observed among the three treatment modalities at any time point for any biochemical parameter.
Conclusions: Levels of several cytokines and acute‐phase proteins significantly changed after treatment regardless of treatment modality. There was no evidence for a specific DSL‐ or PDT‐enhanced expression of inflammatory mediators.
Guiyu, China, is well-known for the crude disposal of electronic waste (EW) and severe persistent organic pollutants (POPs). Therefore, in this study, the occurrence, composition, and source of ...polybrominated diphenyl ethers (PBDEs), 2,2′,4,4′,5,5’-hexabromobiphenyl (BB153), some novel brominated flame retardants (NBFRs), Dechlorane Plus (DP) and polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs) in farmland soils covering Guiyu were studied. In EW disposal area soils, PBDEs were the most abundant FRs, with concentrations of 13–1014 ng g−1. The primary PBDE sources were technical Penta- and Deca-BDE mixtures in northern and southern Guiyu, respectively. The levels of BB153 were relatively low, possibly because it has been banned in the 1970s. The concentrations of hexabromobenzene (HBB) were 0.048–3.3 ng g−1, while pentabromoethylbenzene (PBEB) was almost not detected in the soils. Two alternatives to commercial PBDEs, decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), were the primary NBFRs, with concentrations of 1.8–153 ng g−1 and 0.43–15 ng g−1, respectively. DP was another primary FR, with concentrations of 0.57–146 ng g−1. Moreover, syn-DP and anti-DP isomers were not stereoselectively decomposed during the EW disposal process and were therefore present in their original fractions in the soils. The levels of PBDD/Fs in EW disposal area soils were 2.5–17 pg TEQ g−1. 1,2,3,4,6,7,8-HpBDF and OBDF were the dominant congeners, mainly derived from processing, pyrolysis and combustion of BFRs. The regional distribution of pollutants was shown to be related to the disposal manner of EW, with their open thermal disposal tending to release more highly brominated compounds such as BDE209, DBDPE, and 1,2,3,4,6,7,8-HpBDF. Additionally, some riverbank sites were heavily polluted because of nearby point sources, downwind Simapu (SMP) town without EW disposal activity was also contaminated by these pollutants.
Display omitted
•Levels of PBDEs, some NBFRs, DP and PBDD/Fs in Guiyu soils are relatively high.•Levels of FRs in EW disposal area soils are PBDEs > DBDPE > DP ≈ BTBPE > HBB > BB153 > PBEB.•Technical Penta- and Deca-BDE mixtures are the major PBDE sources in Guiyu soils.•PBDD/Fs are derived from the processing, pyrolysis and combustion of BFRs.•Thermal disposal of EW incline to release more highly brominated compounds.
Guiyu soils are mainly polluted by PBDEs, DBDPE, DP, BTBPE and PBDD/Fs, which are derived from the thermal disposal of BFRs, especially for highly brominated compounds.
•A new cleanup material (EMR-Lipid) was evaluated in the analysis of food contaminants.•EMR-Lipid showed excellent lipid removal efficiency, and partial removal of chlorophyll.•To date, this is the ...first peer-reviewed publication on the use of EMR-Lipid.•Validation results were acceptable for most analytes in kale, avocado, salmon, and pork.•Matrix effects were relatively low using analyte protectants in fast GC–MS/MS.
This study demonstrates the application of a novel lipid removal product to the residue analysis of 65 pesticides and 52 environmental contaminants in kale, pork, salmon, and avocado by fast, low pressure gas chromatography – tandem mass spectrometry (LPGC–MS/MS). Sample preparation involves QuEChERS extraction followed by use of EMR-Lipid (“enhanced matrix removal of lipids”) and an additional salting out step for cleanup. The optimal amount of EMR-Lipid was determined to be 500mg for 2.5mL extracts for most of the analytes. The co-extractive removal efficiency by the EMR-Lipid cleanup step was 83–98% for fatty samples and 79% for kale, including 76% removal of chlorophyll. Matrix effects were typically less than ±20%, in part because analyte protectants were used in the LPGC–MS/MS analysis. The recoveries of polycyclic aromatic hydrocarbons and diverse pesticides were mostly 70–120%, whereas recoveries of nonpolar polybrominated diphenyl ethers and polychlorinated biphenyls were mostly lower than 70% through the cleanup procedure. With the use of internal standards, method validation results showed that 76–85 of the 117 analytes achieved satisfactory results (recoveries of 70–120% and RSD≤20%) in pork, avocado, and kale, while 53 analytes had satisfactory results in salmon. Detection limits were 5–10ng/g for all but a few analytes. EMR-Lipid is a new sample preparation tool that serves as another useful option for cleanup in multiresidue analysis, particularly of fatty foods.
PDF
