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How sea urchins face microplastics: Uptake, tissue distribution and immune system response Full text
2020
Murano, Carola | Agnisola, Claudio | Caramiello, Davide | Castellano, Immacolata | Casotti, Raffaella | Corsi, Ilaria | Palumbo, Anna
Plastic pollution represents one of the major threats to the marine environment. A wide range of marine organisms has been shown to ingest microplastics due to their small dimensions (less than 1 mm). This negatively affects some biological processes, such as feeding, energy reserves and reproduction. Very few studies have been performed on the effect of microplastics on sea urchin development and virtually none on adults. The aim of this work was to evaluate the uptake and distribution of fluorescent labelled polystyrene microbeads (micro-PS) in the Mediterranean sea urchin Paracentrotus lividus and the potential impact on circulating immune cells. Differential uptake was observed in the digestive and water vascular systems as well as in the gonads based on microbeads size (10 and 45 μm in diameter). Treatment of sea urchins with particles of both sizes induced an increase of the total number of immune cells already after 24 h. No significant differences were observed among immune cell types. However, the ratio between red and white amoebocytes, indicative of sea urchin healthy status, increased with both particles. This effect was detectable already at 24 h upon exposure to smaller micro-PS (10 μm). An increase of intracellular levels of reactive oxygen and nitrogen species was observed at 24 h upon both micro-PS exposure, whereas at later time these levels became comparable to those of controls. A significant increase of total antioxidant capacity was observed after treatment with 10 μm micro-PS. Overall data provide the first evidence on polystyrene microbeads uptake and tissue distribution in sea urchins, indicating a stress-related impact on circulating immune cells.
Show more [+] Less [-]Affinity zone identification approach for joint control of PM2.5 pollution over China Full text
2020
Yao, Xuefeng | Ge, Baozhu | Yang, Wenyi | Li, Jianjun | Xu, Danhui | Wang, Wei | Zheng, Haitao | Wang, Zifa
In recent years, the Chinese government has made great efforts to jointly control and prevent air pollution, especially fine particulate matter (PM₂.₅). However, these efforts are challenged by technical constraints due to the significant temporal and spatial heterogeneity of PM₂.₅ across China. In this study, the Affinity Zone Identification Approach (AZIA), which combines rotated principal component analysis (RPCA) with revised clustering analysis, was developed and employed to regionalize PM₂.₅ pollution in China based on data from 1496 air quality monitoring sites recorded from 2013 to 2017. Two clustering methods, cluster analysis with statistical test (CAST) and K-center-point (K-medoids) clustering, were compared and revised to eliminate unspecified sites. Site zonation was finally extended to the municipality scale for the convenience of the controlling measures. The results revealed that 17 affinity zones with 5 different labels from clean to heavily polluted areas could be identified in China. The heavily polluted areas were mainly located in central and eastern China as well as Xinjiang Province, with regional average annual PM₂.₅ concentrations higher than 66 μg/m³. The new approach provided more comprehensive and detailed affinity zones than obtained in a previous study (Wang et al., 2015b). The North China Plain and Northeastern China were both further divided into northern and southern parts based on different pollution levels. In addition, five affinity zones were first recognized in western China. The findings provide not only a theoretical basis to further display the temporal and spatial variations in PM₂.₅ but also an effective solution for the cooperative control of air pollution in China.
Show more [+] Less [-]Meteorological variations impeded the benefits of recent NOx mitigation in reducing atmospheric nitrate deposition in the Pearl River Delta region, Southeast China Full text
2020
Zhong, Buqing | Wang, Xuemei | Ye, Lyumeng | Ma, Mingrui | Jia, Shiguo | Chen, Weihua | Yan, Fenghua | Wen, Zhang | Padmaja, Krishnan
The trends and variability of atmospheric nitrogen deposition in the Pearl River Delta (PRD) region for the period 2008–2017 were investigated by integrating ground- and satellite-based observations and a chemical transport model, in order to gauge the effects of emission reductions and meteorological variability. We show that dry deposition observation of oxidized nitrogen decreased at the rate of 2.4% yr⁻¹ for a moderate reduction in NOₓ emissions by 27% in the past decade, while reduced nitrogen presented an increase at the rate of 2.3% yr⁻¹ despite no regulated interventions for NH₃ emissions, which is likely related to changes in atmospheric gas-particle partitioning of NH₃ as reductions in SO₂ and NOₓ emissions. These results coincide with the trends in ground-level concentrations of oxidized and reduced nitrogen compounds in the atmosphere during 2008–2017. The changes in annual deposition fluxes of total oxidized and reduced nitrogen are not statistically significant trends and largely related with the inter-annual variability in their corresponding wet depositions, which reflects combined effects of variability in precipitation amount, and changes in atmospheric nitrogen compounds which dominates wet deposition of the oxidized and reduced forms. The meteorological conditions can mask 34% and 25% decrease in total oxidized and reduced nitrogen deposition on the decadal timescale, respectively. We conclude that meteorology-driven variability probably have masked the full response of oxidized nitrogen deposition to NOₓ emissions reduction. Our results also imply that persistent and integrated emission control strategies on NOₓ and NH₃ are needed to effectively reduce total nitrogen deposition fluxes towards the critical limit in the PRD region.
Show more [+] Less [-]The evaluation of in-site remediation feasibility of Cd-contaminated soils with the addition of typical silicate wastes Full text
2020
Yang, Huifen | Zhang, Ge | Fu, P. (Peng) | Li, Zhen | Ma, Wenkai
In-site remediation is a relatively promising and socially acceptable technique for heavy metal contaminated soils. But the key task is to select cost-effective and environment-friendly amendents for the consideration of practical application. Based on the property of four typical silicate wastes such as straw ash (SA), coal fly ash (CFA), ferronickel slag (FNS) and blast-furnace slag (BFS), effects of four wastes on available Cd content and Cd chemical speciation in amended soils, and physicochemical properties of the amended soils were carried out in the study. The results showed that four wastes were dominately composed of the amorphous phases with OH⁻ ions readily released. When the weight ratio of silicate wastes to artificial Cd-contaminated soils reached 10%, the available Cd contents decreased from 4.12 mg/kg in untreated soils to 1.94, 1.92, 1.45 and 1.53 mg/kg in amended soils by adding SA, CFA, FNS and BFS respectively, after the soils were amended for 30 days. The residual fraction of Cd (R) was 2.54, 2.48, 2.77 and 2.58 times higher in amended soil than that in untreated soil when SA, CFA, FNS and BFS was added, respentively. The soil pH and CEC were improved. The amended soils by adding SA and FNS were looser than those by adding CFA and BFS, and air permeability of the amended soils by SA was better than that by FNS.
Show more [+] Less [-]Emission characteristics and associated assessment of volatile organic compounds from process units in a refinery Full text
2020
Feng, Yunxia | Xiao, Anshan | Jia, Runzhong | Zhu, Shengjie | Gao, Victor | Li, Bo | Shi, Ning | Zou, Bing
The accuracy and reliability of volatile organic compound (VOC) emission data are essential for assessing emission characteristics and their potential impact on air quality and human health. This paper describes a new method for determining VOC emission data by multipoint sampling from various process units inside a large-scale refinery. We found that the emission characteristics of various production units were related to the raw materials, products, and production processes. Saturated alkanes accounted for the largest fraction in the continuous catalytic reforming and wastewater treatment units (48.0% and 59.2%, respectively). In the propene recovery unit and catalytic cracking unit, alkenes were the most dominant compounds, and propene provided the largest contributions (57.8% and 23.0%, respectively). In addition, n-decane (12.6%), m,p-xylene (12.4%), and n-nonane (8.9%) were the main species in the normal production process of the delayed coking unit. Assessments of photochemical reactivity and carcinogenic risk were carried out, and the results indicate that VOC emissions from the propene recovery unit and catalytic cracking unit should be controlled to reduce the ozone formation potential; in addition, alkenes are precedent-controlled pollutants. The cancer risk assessments reveal that 1,2-dibromoethane, benzene, 1,2-dichloroethane, and chloroform were the dominant risk contributors, and their values were much higher than the standard threshold value of 1.0 × 10⁻⁶ but lower than the significant risk value defined by the US Supreme Court. Based on the VOC composition and a classification algorithm, the samples were classified into eight main groups that corresponded to different process units in the petroleum refinery. In conclusion, this work provides valuable data for investigating process-specific emission characteristics of VOCs and performing associated assessments of photochemical reactivity and carcinogenic risk in petrochemical refineries.
Show more [+] Less [-]High throughput analysis of 21 perfluorinated compounds in drinking water, tap water, river water and plant effluent from southern China by supramolecular solvents-based microextraction coupled with HPLC-Orbitrap HRMS Full text
2020
Liang, Ming | Xian, Yanping | Wang, Bin | Hou, Xiangchang | Wang, Li | Guo, Xindong | Wu, Yuluan | Dong, Hao
The present work reported a high-throughput strategy for the analysis of 21 perfluorinated compounds (PFCs) in drinking water, tap water, river water and plant effluent from southern China by supramolecular solvent (SUPARS) vortex-mixed microextraction combined with high performance liquid chromatography-Orbitrap high resolution mass spectrometry (HPLC-Orbitrap HRMS). The SUPRAS without heating assistance is less solvent-consumption, meeting the requirements for green environmental protection and sustainable development. Parameters in the microextraction such as volume of dodecanol and tetrahydrofuran (THF), vortexing extraction and centrifugation time, salt concentration were investigated. The optimal extraction conditions were 250 μL of undecanol, 1.0 mL of THF and 20.0% (w/v, 4 g) NaCl. Under the optimum conditions, method limit of detection and method limit of quantitation in the ranges of 0.01–0.08 μg/L and 0.03–0.25 μg/L, good recoveries (72.5–117.8%) and intra-day precision (1.1–11.2%, n = 6), high enrichment factors (48–78) were obtained. The developed method was successfully applied for analysis of PFCs in 13 drinking water, tap water, river water and plant effluent samples collected from southern China. Perfluorobutane sulfonic acid was detected in one river water with concentration of 0.48 μg/L and 1H,1H,2H,2H-Perfluorooctane sulfonic acid was detected in one river water and two plant effluent samples with concentrations in the range of 0.14–0.67 μg/L.
Show more [+] Less [-]Morphological deformation of Daphnia magna embryos caused by prolonged exposure to ibuprofen Full text
2020
Grzesiuk, Malgorzata | Pijanowska, Joanna | Markowska, Magdalena | Bednarska, Anna
The effect of chronic exposure of freshwater cladoceran Daphnia magna to low, environmentally relevant concentrations i.e 4 μgL⁻¹of ibuprofen (a nonsteroidal anti-inflammatory drug) in a laboratory experiment was studied. We observed the key life history traits of first and fifth generation individuals: age and size at first reproduction, number of first clutch eggs and individual growth rate. Moreover, chosen molecular/subcellular markers of experimental animals stress response such as triglyceride content, heat shock proteins (HSP) expression and DNA:RNA ratio were collected. Overall, chronic exposure to ibuprofen had no significant effect on the molecular markers nor on the life history parameters of the Daphnia. It did, however, caused lethal morphological deformities in embryos and juvenile daphnids. Depending on the clonal affiliation, exposure to a low dosage of ibuprofen over five generations resulted in the deformation of ∼3%–∼10% of the first clutch of offspring. Also, up to 90% of females carried at least one deformed embryo. This is the first time that research has revealed such an effect of ibuprofen on D. magna.
Show more [+] Less [-]The association between ambient temperature and clinical visits for inflammation-related diseases in rural areas in China Full text
2020
Wang, Qingan | Zhao, Qi | Wang, Guoqi | Wang, Binxia | Zhang, Yajuan | Zhang, Jiaxing | Li, Nan | Zhao, Yi | Qiao, Hui | Li, Wuping | Liu, Xiuying | Liu, Lan | Wang, Faxuan | Zhang, Yuhong | Guo, Yuming
The association between temperature and mortality has been widely reported. However, it remains largely unclear whether inflammation-related diseases, caused by excessive or inappropriate inflammatory reaction, may be affected by ambient temperature, particularly in low-income areas.To explore the association between ambient temperature and clinical visits for inflammation-related diseases in rural villages in the Ningxia Hui Autonomous Region, China, during 2012─2015.Daily data on inflammation-related diseases and weather conditions were collected from 258 villages in Haiyuan (161 villages) and Yanchi (97 villages) counties during 2012─2015. A Quasi-Poisson regression with distributed lag non-linear model was used to examine the association between temperature and clinical visits for inflammation-related diseases. Stratified analyses were performed by types of diseases including arthritis, gastroenteritis, and gynecological inflammations.During the study period, there were 724,788 and 288,965 clinical visits for inflammation-related diseases in Haiyuan and Yanchi, respectively. Both exposure to low (RR: 2.045, 95% CI: 1.690, 2.474) and high temperatures (RR: 1.244, 95% CI: 1.107, 1.399) were associated with increased risk of total inflammation-related visits in Haiyuan county. Low temperatures were associated with increased risks of all types of inflammation-related diseases in Yanchi county (RR: 4.344, 95% CI: 2.887, 6.535), while high temperatures only affected gastroenteritis (RR: 1.274, 95% CI: 1.040, 1.561). Moderate temperatures explained approximately 26% and 33% of clinical visits due to inflammation-related diseases in Haiyuan and Yanchi, respectively, with the burden attributable to cold exposure higher than hot exposure. The reference temperature values ranged from 17 to 19 in Haiyuan, and 12 to 14 in Yanchi for all types of clinical visits.Our findings add additional evidence for the adverse effect of suboptimal ambient temperature and provide useful information for public health programs targeting people living in rural villages.
Show more [+] Less [-]Fine sediment particle microscopic characteristics, bioavailable phosphorus and environmental effects in the world largest reservoir Full text
2020
Wang, Xiaoxiao | Zhou, Jun | Wu, Yanhong | Bol, Roland | Wu, Yong | Sun, Hongyang | Bing, Haijian
The transport and retention of sediments in fine grain sizes plays an important role in the cycles of phosphorus (P), and is closely related to the extent and potential for eutrophication in water reservoirs. In order to highlight the environmental indications for the transport of fine sediment particles and the associated bioavailable phosphorus (Bio-P) in the world largest reservoir, the Three Gorges Reservoir (TGR), the suspended and bed sediments were collected at 13 sections in 2016. The sediment physicochemical properties, micromorphology of sediment particles, distribution of elements on particle surface, P adsorption parameters, and P fractions in different grain sized sediments were analyzed. The results showed that the fine sediment particles had a strong P adsorption ability due to their micromorphology, mineral compositions, and the high contents of Fe/Al/Mn (hydr)oxides, which contributed a higher concentration of Bio-P in <16 μm sediment particles. The adsorption of P on the sediment particles occurred longitudinally along the TGR, and the fine sediment particles (<16 μm) dominated the transport and distribution of Bio-P in the TGR sediments. The reduced inflow and retention of fine sediment particles, caused by the construction of cascade reservoirs along the Jinsha River (upper reach of the Yangtze River), has resulted in the decrease in the retention of Bio-P in the TGR. Therefore, we conclude that the continuously decrease of inflow and retention of the fine sediment particles in the TGR, and with it a reduced sediment P buffer capacity, may enhance algal blooms occurrence also in view of the increased P discharge from the overall TGR catchment. The study results can contribute to improved management guidance on fine sediment particles and associated phosphorus for the operation and environmental protection of other large reservoirs in the world.
Show more [+] Less [-]Sensitivity of larval and juvenile freshwater mussels (unionidae) to ammonia, chloride, copper, potassium, and selected binary chemical mixtures Full text
2020
Salerno, J. | Gillis, P.L. | Khan, H. | Burton, Evan | Deeth, L.E. | Bennett, C.J. | Sibley, P.K. | Prosser, R.S.
In aquatic environments, organisms such as freshwater mussels are likely exposed to complex contaminant mixtures related to industrial, agricultural, and urban activities. With growing interest in understanding the risk that chemical mixtures pose to mussels, this investigation focused on the effects of various waterborne contaminants (ammonia, chloride, copper, and potassium) and selected binary mixtures of these chemicals following a fixed-ratio design to Villosa iris glochidia and juvenile Lampsilis fasciola. In individual exposures, 48-h EC50 values were determined for V. iris glochidia exposed to ammonia chloride (7.4 [95% confidence interval (CI) 6.6–8.2] mg N/L), ammonia sulfate (8.4 [7.6–9.1] mg N/L), copper sulfate (14.2 [12.9–15.4] μg Cu2+/L), potassium chloride (12.8 [11.9–13.7] mg K+/L), potassium sulfate (10.1 [8.9–11.2] mg K+/L), and sodium chloride (480.5 [435.5–525.5] mg Cl−/L). The 7-d LC50 values for juvenile L. fasciola were determined for potassium sulfate (45.0 [18.8–71.2] mg K+/L), and sodium chloride (1738.2 [1418.6–2057.8] mg Cl−/L). In Ontario these waterborne contaminants have been reported to co-occur, with concentrations exceeding the EC10 for both life stages at some locations. Data from binary mixture exposures for V. iris glochidia (chloride-ammonia, chloride-copper, and copper-ammonia) and juvenile L. fasciola (chloride-potassium) were analyzed using a regression-based, dose-response mixture analysis modeling framework. Results from the mixture analysis were used to determine if an additive model for mixture toxicity [concentration addition (CA) or independent action (IA)] best described the toxicity of each mixture and if deviation towards dose-ratio (DR) or dose-level (DL) synergism/antagonism (S/A) occurred. For all glochidia binary mixture exposures, CA was the best fit model with DL deviation reported for the chloride-copper mixture and DR deviation reported for the copper-ammonia mixture. Using the model deviation ratio (MDR), the observed toxicity in all three glochidia mixture exposures were adequately described by both CA (mean = 0.71) and IA (mean = 0.97) whereas the juvenile mixture exposure was only adequately described by CA (mean = 0.64; IA mean = 0.05).
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