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Результаты 1441-1450 из 7,921
Multi-elemental profile and enviromagnetic analysis of moss transplants exposed indoors and outdoors in Italy and Belgium
2021
Sorrentino, Maria Cristina | Wuyts, Karen | Joosen, Steven | Mubiana, Valentine K. | Giordano, Simonetta | Samson, Roeland | Capozzi, Fiore | Spagnuolo, Valeria
Air pollution represents one of the major concerns worldwide, fueled by the increasing urbanization and related PM production worsening air quality in open air as well as in confined environments. In the present work, exposure to atmospheric metal pollution was investigated in 20 paired indoor (I)-outdoor (O) sites located in two urban areas of Italy and Belgium, by chemical (ICP-MS) and magnetic (saturation isothermal remanent magnetization, SIRM) analyses of Hypnum cupressiforme moss exposed in bags. After 12 weeks, the elemental profiles of the moss material exposed in the two countries largely overlapped, except for some elements which specifically accumulated in Belgium (Ag, As, Cd, Mo, Pb and Sb) and in Italy (Ca, Mg, Co, Cr, Sr, Ti and U). Element concentrations were higher in moss exposed outdoors, with the Italian sites mostly showing a terrigenous footprint, and the Belgian sites mostly affected by elements of environmental concern (e.g., As, Pb, Sb). The Indoor/Outdoor ratios (mostly lower than 0.75) indicated indoor pollution as strongly affected by outdoor pollution, although specific elements could be of indoor origin or magnified in indoor environments (e.g., Al, Ag, Cd and Co). In line with the chemical analysis, the SIRM signal was significantly higher in outdoor than indoor moss material. A positive, significant correlation was observed between SIRM and several accumulated elements indicating SIRM analysis as a powerful tool to predict the level of metal pollution. Moss bags were confirmed as a useful and versatile tool to highlight metal contamination even in confined environments, an essential prerogative in the perspective of the evaluation of the total exposure risk for humans to these pollutants.
Показать больше [+] Меньше [-]Multigeneration toxicity of Geunsami® (a glyphosate-based herbicide) to Allonychiurus kimi (Lee) (Collembola) from sub-individual to population levels
2021
Wee, June | Lee, Yun-Sik | Kim, Yongeun | Lee, Yong Ho | Lee, Sung-Eun | Hyun, Seunghun | Cho, Kijong
Glyphosate-based herbicide (GBH) is the most widely used herbicide worldwide and has long been considered to have significantly low toxicity to non-target soil invertebrates based on short-term toxicity tests (<56 d). However, long-term GBH toxicity assessment is necessary as GBH is repeatedly applied in the same field annually because of the advent of glyphosate-resistant crops. In this study, a multigeneration test was conducted where Allonychiurus kimi (Collembola) was exposed to GBH for three generations (referred to as F₀, F₁, and F₂) to evaluate the long-term toxic effect. The endpoints used were adult survival and juvenile production for the individual level toxicity assessment. Phospholipid profile and population age structure were the endpoints used for sub-individual and population levels, respectively. GBH was observed to have no negative effects on adult survivals of all generations, but juvenile production was found to decrease in a concentration-dependent manner, with EC₅₀s being estimated as 572.5, 274.8, and 59.8 mg a.i. kg⁻¹ in the F₀, F₁, and F₂ generations, respectively. The age structure of A. kimi population produced in the test of all generations was altered by GBH exposure, mainly because of the decrease in the number of young juveniles. Further, differences between the phospholipid profiles of the control and GBH treatments became apparent over generations, with PA 16:0, PA 12:0, and PS 42:0 lipids not being detected at the highest concentration of 741 mg kg⁻¹ in F₂. Considering all our findings from sub-individual to population levels, repeated and long-term use of GBH could have significantly higher negative impacts on non-target soil organisms than expected.
Показать больше [+] Меньше [-]Association between traffic-related air pollution and hospital readmissions for rheumatoid arthritis in Hefei, China: A time-series study
2021
Wu, Qian | Xu, Zhiwei | Dan, Yi-Lin | Cheng, Jian | Zhao, Chan-Na | Mao, Yan-Mei | Xiang, Kun | Hu, Yu-Qian | He, Yi-Sheng | Pan, Hai-Feng
Air pollution is an important risk factor for autoimmune diseases, but its association with the recurrence of rheumatoid arthritis (RA) remains unclear so far. This study aimed to investigate the short-term association between traffic-related air pollutants and hospital readmissions for RA in Hefei, China. Data on daily hospital readmissions for RA and traffic-related air pollutants, including particulate matter (PM₂.₅ and PM₁₀), nitrogen dioxide (NO₂), and carbon monoxide (CO), from 2014 to 2018 were retrieved. A time-series approach using generalized linear regression model was employed. The analysis was further stratified by sex, age and season. A total of 1153 readmissions for RA were reported during the study period. A significant association between high-concentration PM₂.₅ (90th percentile) and RA readmissions was observed on lag1 (relative risk (RR) = 1.09, 95% confidence interval (CI): 1.01–1.19) and lasted until lag3 (RR = 1.06, 95%CI: 1.01–1.12). From lag2 to lag5, high-concentration NO₂ (90th percentile) was associated with increased risk of RA readmissions, with the highest RR observed at lag 4 (1.11, 95%CI: 1.05–1.17). Stratified analyses indicated that females and the elderly appeared to be more vulnerable to high-concentration PM₂.₅ and NO₂ exposure. High-concentration PM₂.₅ and NO₂ in cold seasons were consistently significantly associated with increased risk of RA readmissions. Exposure to high-concentration PM₂.₅ and NO₂ was associated with increased risk of RA readmissions. Protective measures against the exposure to high-concentration PM₂.₅ and NO₂ should be taken to reduce the recurrence risk in RA patients, especially in females, the elderly and during cold seasons.
Показать больше [+] Меньше [-]Environmental aspects of UV-C-based processes for the treatment of oxytetracycline in water
2021
Stankov, Vladimir | Stankov, Mirjana Novak | Cvetnić, Matija | Sigurnjak Bureš, Marija | Ukić, Šime | Kučić Grgić, Dajana | Lončarić Božić, Ana | Kusic, Hrvoje | Bolanča, Tomislav
This study is focused on oxytetracycline (OTC) degradation by direct photolysis (UV–C) and photobased advanced oxidation processes (AOPs) (UV–C/H₂O₂ and UV-C/S₂O₈²⁻). OTC degradation pathways were revealed by LC-MS/MS and GC-MS/MS analyses. The evolution/degradation profiles of 12 detected byproducts were correlated with changes in biodegradability and toxicity toward Vibrio fischeri recorded during the treatment. Both photobased AOPs yielded higher OTC degradation and mineralization rates than direct photolysis. The OTC degradation pathway was found to be rather specific regarding the main reactive species (HO• or SO₄•⁻)/mechanism, yielding different patterns in toxicity changes, while biodegradability profiles were less affected. Biodegradability was correlated with the observed degradation and mineralization kinetics. The recorded toxicity changes indicate that byproducts formed by initial OTC degradation are more toxic than the parent pollutant. The prolonged treatment resulted in the formation of byproducts that contributed to a decrease in toxicity and an increase in biodegradability, as particularly emphasized in the case of UV-C/S₂O₈²⁻.
Показать больше [+] Меньше [-]Alkylated polycyclic aromatic hydrocarbons are the largest contributor to polycyclic aromatic compound concentrations in traditional foods of the Bigstone Cree Nation in Alberta, Canada
2021
Golzadeh, Nasrin | Barst, Benjamin D. | Baker, Janelle M. | Auger, Josie C. | McKinney, Melissa A.
Rising global demand for energy promotes extensive mining of natural resources, such as oil sands extractions in Alberta, Canada. These extractive activities release hazardous chemicals into the environment, such as polycyclic aromatic compounds (PACs), which include the parent polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs, and sulfur-containing heterocyclic dibenzothiophenes (DBTs). In areas adjacent to industrial installations, Indigenous communities may be exposed to these PACs through the consumption of traditional foods. Our objective was to evaluate and compare the concentrations of total PACs (∑PAC), expressed as the sum of the 16 U.S. EPA priority PAHs (∑PAH), 49 alkylated PAHs (∑alkyl-PAH), and 7 DBTs (∑DBT) in plant and animal foods collected in 2015 by the Bigstone Cree Nation in Alberta, Canada. We analyzed 42 plant tissues, 40 animal muscles, 5 ribs, and 4 pooled liver samples. Concentrations of ∑PAC were higher in the lichen, old man’s beard (Usnea spp.) (808 ± 116 ng g⁻¹ w.w.), than in vascular plants, and were also higher in smoked moose (Alces alces) rib (461 ± 120 ng g⁻¹ w.w.) than in all other non-smoked animal samples. Alkylated-PAHs accounted for between 63% and 95% of ∑PAC, while the concentrations of ∑PAH represented 4%–36% of ∑PAC. Contributions of ∑DBT to ∑PAC were generally lowest, ranging from <1% to 14%. While the concentrations of benzo(a)pyrene (B[a]P) and ∑PAH4 (∑benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and B[a]P) in all samples were below guideline levels for human consumption as determined by the European Commission, guideline levels for the more prevalent alkylated PAHs are not available. Given the predominance of alkylated PAHs in all food samples and the potentially elevated toxicity relative to parent PAHs of this class of PACs, it is critical to consider a broader range of PACs other than just parent PAHs in research conducted close to oil sands mining activities.
Показать больше [+] Меньше [-]Opposite impact of emission reduction during the COVID-19 lockdown period on the surface concentrations of PM2.5 and O3 in Wuhan, China
2021
Yin, Hao | Liu, Cheng | Hu, Qihou | Liu, Ting | Wang, Shuntian | Gao, Meng | Xu, Shiqi | Zhang, Chengxin | Su, Wenjing
To prevent the spread of the COVID-19 epidemic, the Chinese megacity Wuhan has taken emergent lockdown measures starting on January 23, 2020. This provided a natural experiment to investigate the response of air quality to such emission reductions. Here, we decoupled the influence of meteorological and non-meteorological factors on main air pollutants using generalized additive models (GAMs), driven by data from the China National Environmental Monitoring Center (CNEMC) network. During the lockdown period (Jan. 23 – Apr. 8, 2020), PM₂.₅, PM₁₀, NO₂, SO₂, and CO concentrations decreased significantly by 45 %, 49 %, 56 %, 39 %, and 18 % compared with the corresponding period in 2015–2019, with contributions by S(meteos) of 15 %, 17 %, 13 %, 10 %, and 6 %. This indicates an emission reduction of NOₓ at least 43 %. However, O₃ increased by 43 % with a contribution by S(meteos) of 6 %. In spite of the reduced volatile organic compound (VOC) emissions by 30 % during the strict lockdown period (Jan. 23 – Feb. 14, 2020), which likely reduced the production of O₃, O₃ concentrations increased due to a weakening of the titration effect of NO. Our results suggest that conventional emission reduction (NOₓ reduction only) measures may not be sufficient to reduce (or even lead to an increase of) surface O₃ concentrations, even if reaching the limit, and VOC-specific measures should also be taken.
Показать больше [+] Меньше [-]A new classification approach to enhance future VOCs emission policies: Taking solvent-consuming industry as an example
2021
Zhang, Xinmin | Zhao, Wenjuan | Nie, Lei | Shao, Xia | Dang, Hongyan | Zhang, Weiqi | Wang, Di
Volatile organic compounds (VOCs) has consistently been linked to ozone (O₃) and secondary organic aerosol (SOA) formation, and ongoing emission policies are primarily focusing on total VOCs without addressing the association between regulation measures and secondary pollution characteristic. For enhancing VOCs emission policy, we investigated potential formation of O₃ and SOA based on analyses of node-specific VOCs concentration and species distribution in solvent-consuming industry. Although aromatics were found to contribute most to O₃ and SOA formation averagely (2.57 ± 2.14 g O₃/g VOCs, 1.91 ± 1.67 g SOA/g VOCs), however, large disparity concerning emission and secondary pollution profile were identified among different emission nodes which demonstrated that regulation policy should be formulated based on comprehensive pollution characteristic. Therefore, emission nodes were classified into four clusters through data normalization, formatting and classification process, including aromatics dominated (7 emission nodes), aromatics-alkene dominated (4 emission nodes), aromatics-alcohols dominated (4 emission nodes) and alcohols dominated (4 emission nodes). And different dominating VOCs species were further obtained in each cluster. Subsequently, focusing regulation measures of reducing O₃ and SOA for different emission source clusters were proposed to guide pollution prevention and enhance future VOCs emission policies.
Показать больше [+] Меньше [-]Performance of faecal indicator bacteria, microbial source tracking, and pollution risk mapping in tropical water
2021
Goshu, Goraw | Koelmans, A.A. | de Klein, J.J.M.
Faecal indicator bacteria (FIB) are used for the assessment of faecal pollution and possible water quality deterioration. There is growing evidence that FIB used in temperate regions are not adequate and reliable to detect faecal pollution in tropical regions. Hence, this study evaluated the adequacy of FIB, including total coliforms (TC), Escherichia coli (EC), Enterococci (IEC), and Clostridium perfringens (CP) in the high-altitude, tropical country of Ethiopia. In addition to FIB, for microbial source tracking (MST), a ruminant-associated molecular marker was applied at different water types and altitudes, and faecal pollution risk mapping was conducted based on consensus FIB. The performances of the indicators were evaluated at 22 sites from different water types. The results indicate that EC cell enumeration and CP spore determination perform well for faecal contamination monitoring. Most of the sub-basins of Lake Tana were found to be moderately to highly polluted, and the levels of pollution were demonstrated to be higher in the rainy season than in the post-rainy season. Markers associated with ruminants (BacR) were identified in more than three quarters of the sites. A bacterial pollution risk map was developed for sub-basins of Lake Tana, including the un-gauged sub-basins. We demonstrate how bacterial pollution risk mapping can aid in improvements to water quality testing and reduce risk to the general population from stream bacteria.
Показать больше [+] Меньше [-]Fate and budget of poly- and perfluoroalkyl substances in three common garden plants after experimental additions with contaminated river water
2021
McDonough, Andrew M. | Bird, Adam W. | Freeman, Lindsay M. | Luciani, Michael A. | Todd, Aaron K.
Poly- and perfluoroalkyl substances (PFAS) have become ubiquitous contaminants in the environment. Contamination of the terrestrial ecosystem can occur from the release of aqueous film forming foams (AFFF) used in firefighting operations. Following soil contamination with AFFF, studies report root uptake and translocation of PFAS to other plant organs, typically favouring the short chain moiety. This body of experimental work often focuses on edible organs and generally lacks entire PFAS budgets. Here, we calculate short chain (≤6 carbons) and long chain (≥6 or ≥ 7 carbons) PFAS concentrations and respective budgets for terrestrial multimedia mesocosms (plants, soil and lysimeter) of three common agricultural plants (tomato, lettuce and beet) following irrigation with low level PFAS (<1 μg L⁻¹) contaminated river water (short chain: 167 ng L⁻¹; long chain 526 ng L⁻¹). Total net recoveries were strong, ranging between 91% and 118% of added PFAS across all media. While soil was the largest receptor of PFAS in general (∼70% and 115%), there was considerable mobility to various media, including vegetation (∼3% and 20%) and leachate (∼1%). Translocation of short chain PFAS to tomato flowers resulted with biomagnified concentrations (maximus >4000 ng g⁻¹) and accounted for 1.4% of PFAS additions. While smaller tomato fruits had higher concentrations of short chain PFAS, larger fruit had more total PFAS mass. This work provides a detailed description of the fate of short and long chain PFAS when added to relatively uncontaminated terrestrial agricultural systems. We show low-level PFAS concentrations from real-world irrigation sources can affect various receptors across the multimedia landscape. This is most evident in tomato flowers and fruit where biomagnification and high total masses of short chain PFAS occurred which could have implications for pollinators and consumption, respectively.
Показать больше [+] Меньше [-]Hotspots of reactive nitrogen loss in China: Production, consumption, spatiotemporal trend and reduction responsibility
2021
Luo, Zhibo | Liang, Xia | Lam, Shu Kee | Mosier, Arvin R. | Hu, Shanying | Chen, Deli
Effective and fair mitigation measures hinge on the identification of hotspots and tracking provenance on reactive nitrogen (Nr) loss at a high spatial resolution. We assessed the Nr loss intensity in China at 1 km spatial resolution from 1980 to 2015. The total Nr loss increased from 20.2 to 54.5 Tg N yr⁻¹, with hotspots (>100 kg N ha⁻¹ yr⁻¹) concentrated in the North China Plain, the Middle and Lower Yangtze River and the Sichuan Basin. The Nr loss hotspots covered less than 20% of the Chinese territory but contributed more than 90% of total Nr loss since 1990. Geographical disparity in Nr loss has increased and calls for a fair regional policy synergy. Compared to managing Nr loss based only on production, we demonstrate that the estimation of Nr loss responsibility driven by consumption has greater potential to allocate a fair share of responsibility for reducing Nr loss.
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