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Seasonal and annual variations in removal efficiency of perfluoroalkyl substances by different wastewater treatment processes Full text
2018
Chen, Shuqin | Zhou, Yunqiao | Meng, Jing | Wang, Tieyu
Municipal wastewater treatment plants (WWTPs) are important in the migration and transformation of perfluoroalkyl substances (PFASs) in water bodies. Six municipal WWTPs located in the upper reaches of the Guanting reservoir, along the Yanghe River, were sampled from November 2016 to July 2017. Influents, effluents, and activated sludge solutions were sampled and the concentrations of 17 PFASs were analyzed. Perfluorobutanoic acid (PFBA), Perfluorooctanoic acid (PFOA), Perfluorohexanoic acid (PFHxA), Perfluoropentanoic acid (PFPeA), Perfluorobutane sulfonat (PFBS) and Perfluorooctane sulfonate (PFOS) accounted for more than 90% of these. Seasonal variations in PFASs in influent directly influenced concentrations in supernatant and effluent. The annual average PFAS concentrations were 46.4, 45.1, and 38.5 ng L⁻¹ in influent, supernatant, and effluent, respectively, indicating that WWTPs do not efficiently remove PFASs from wastewater. Annual average PFAS removal efficiencies differed among WWTPs, were influenced primarily by the treatment process used at each, and followed the order Cyclic Activated Sludge System (CASS, 32.2%) > Orbal Oxidation Ditch (OD, 17.5%) > Anaeroxic–Anoxic–Oxic (A²/O, −1.49%). Short-chain PFASs were removed significantly more efficiently in the CASS compared to the other systems. These results can show how traditional wastewater treatment plants can help remove PFASs from the environment.
Show more [+] Less [-]Fertilizer application in rural cropland drives cadmium enrichment in bats dwelling in an urban area Full text
2018
Liu, Sha | Yu, Wenhua | Li, Feng | Zhao, Jing | Yin, Ru-Yi | Zhou, Zhao-Min | Pan, Bo
The transfer of pollutants from chemical fertilizers through food webs within cropland is well documented; however, its impacts on the wild animals that forage on croplands but roost in other locations remain poorly understood. The potential for this cross-ecosystem ‘spillover’ of pollutants is greatest for bats, some of which exploit urban settlements as roosting niches but must travel long distances to reach croplands as foraging niches. Here, we used hairs from a colony of insectivorous bats, Chinese Noctule (Nyctalus plancyi), from an urban area in Southwest China to assess whether exposure to heavy metals/metalloids by the bats varied from 1975 to 2016. Historical changes occurred in hair cadmium (Cd) concentrations in adult females, which was exclusively explained by the regional fertilizer application intensity (FAI), even considering the potential impacts of Cd emissions in urban areas, as indicated by camphor trees (Cinnamomum camphora) near the bats' roosting niche, and the potential impacts of Cd in industrial wastewater, as documented in authorized databases. Therefore, the data from this bat colony, as urban dwellers, indicates Cd accumulation and cross-ecosystem transfer from rural croplands to an urban area.
Show more [+] Less [-]Ambient fine and coarse particles in Japan affect nasal and bronchial epithelial cells differently and elicit varying immune response Full text
2018
Onishi, Toshinori | Honda, Akiko | Tanaka, Michitaka | Chowdhury, Pratiti H. | Okano, Hitoshi | Okuda, Tomoaki | Shishido, Daiki | Terui, Yoshihiro | Hasegawa, Shuichi | Kameda, Takayuki | Tohno, Susumu | Hayashi, Masahiko | Nishita-Hara, Chiharu | Hara, Keiichiro | Inoue, Kozo | Yasuda, Makoto | Hirano, Shigeru | Takano, Hirohisa
Ambient particulate matter (PM) epidemiologically exacerbates respiratory and immune health, including allergic rhinitis (AR) and bronchial asthma (BA). Although fine and coarse particles can affect respiratory tract, the differences in their effects on the upper and lower respiratory tract and immune system, their underlying mechanism, and the components responsible for the adverse health effects have not been yet completely elucidated. In this study, ambient fine and coarse particles were collected at three different locations in Japan by cyclone technique. Both particles collected at all locations decreased the viability of nasal epithelial cells and antigen presenting cells (APCs), increased the production of IL-6, IL-8, and IL-1β from bronchial epithelial cells and APCs, and induced expression of dendritic and epithelial cell (DEC) 205 on APCs. Differences in inflammatory responses, but not in cytotoxicity, were shown between both particles, and among three locations. Some components such as Ti, Co, Zn, Pb, As, OC (organic carbon) and EC (elemental carbon) showed significant correlations to inflammatory responses or cytotoxicity. These results suggest that ambient fine and coarse particles differently affect nasal and bronchial epithelial cells and immune response, which may depend on particles size diameter, chemical composition and source related particles types.
Show more [+] Less [-]Characterization of airborne particles emitted by an electrically heated tobacco smoking system Full text
2018
Pacitto, A. | Stabile, L. | Scungio, M. | Rizza, V. | Buonanno, G.
Smoking activities were recognized as a main risk factor for population. Indeed, mainstream smoke aerosol is directly inhaled by smokers then delivering harmful compounds in the deepest regions of the lung. In order to reduce the potential risk of smoking, different nicotine delivery products have been recently developed. The latest device released is an electrically heated tobacco system (iQOS®, Philip Morris) which is able to warm the tobacco with no combustion. In the present paper a dimensional and volatility characterization of iQOS-generated particles was performed through particle number concentration and distribution measurements in the mainstream aerosol. The experimental analysis was carried out through a condensation particle counter, a fast mobility particle sizer and a thermo-dilution sampling system allowing aerosol samplings at different temperatures. Estimates of the particle surface area dose received by smokers were also carried out on the basis of measured data and typical smoking patterns.The particle number concentrations in the mainstream aerosols resulted lower than 1 × 108 part. cm−3 with particle number distribution modes of about 100 nm. Nonetheless, the volatility analysis showed the high amount of volatile fraction of iQOS-generated particles, indeed, samplings performed at 300 °C confirmed a significant particle shrinking phenomena (modes of about 20 nm). Anyway, the particle number concentration does not statistically decrease at higher sampling temperatures, then showing that a non-volatile fraction is always presents in the emitted particles. The dose received by smokers in terms of non-volatile amount of particle surface area was equal to 1–2 mm2 per puff, i.e. up to 4-fold larger than that received by electronic cigarette vapers.
Show more [+] Less [-]Sources and distribution of microplastics in China's largest inland lake – Qinghai Lake Full text
2018
Xiong, Xiong | Zhang, Kai | Chen, Xianchuan | Shi, Huahong | Luo, Ze | Wu, Chenxi
Microplastic pollution was studied in China's largest inland lake – Qinghai Lake in this work. Microplastics were detected with abundance varies from 0.05 × 10⁵ to 7.58 × 10⁵ items km⁻² in the lake surface water, 0.03 × 10⁵ to 0.31 × 10⁵ items km⁻² in the inflowing rivers, 50 to 1292 items m⁻² in the lakeshore sediment, and 2 to 15 items per individual in the fish samples, respectively. Small microplastics (0.1–0.5 mm) dominated in the lake surface water while large microplastics (1–5 mm) are more abundant in the river samples. Microplastics were predominantly in sheet and fiber shapes in the lake and river water samples but were more diverse in the lakeshore sediment samples. Polymer types of microplastics were mainly polyethylene (PE) and polypropylene (PP) as identified using Raman Spectroscopy. Spatially, microplastic abundance was the highest in the central part of the lake, likely due to the transport of lake current. Based on the higher abundance of microplastics near the tourist access points, plastic wastes from tourism are considered as an important source of microplastics in Qinghai Lake. As an important area for wildlife conservation, better waste management practice should be implemented, and waste disposal and recycling infrastructures should be improved for the protection of Qinghai Lake.
Show more [+] Less [-]A proposed methodology for impact assessment of air quality traffic-related measures: The case of PM2.5 in Beijing Full text
2018
Fontes, Tânia | Li, Peilin | Barros, Nelson | Zhao, Pengjun
Air quality traffic-related measures have been implemented worldwide to control the pollution levels of urban areas. Although some of those measures are claiming environmental improvements, few studies have checked their real impact. In fact, quantitative estimates are often focused on reducing emissions, rather than on evaluating the actual measures’ effect on air quality. Even when air quality studies are conducted, results are frequently unclear.In order to properly assess the real impact on air quality of traffic-related measures, a statistical method is proposed. The method compares the pollutant concentration levels observed after the implementation of a measure with the concentration values of the previous year. Short- and long-term impact is assessed considering not only their influence on the average pollutant concentration, but also on its maximum level. To control the effect of the main confounding factors, only the days with similar environmental conditions are analysed. The changeability of the key meteorological variables that affect the transport and dispersion of the pollutant studied are used to identify and group the days categorized as similar. Resemblance of the pollutants' concentration of the previous day is also taken into account. The impact of the road traffic measures on the air pollutants’ concentration is then checked for those similar days using specific statistical functions.To evaluate the proposed method, the impact on PM₂.₅ concentrations of two air quality traffic-related measures (M1 and M2) implemented in the city of Beijing are taken into consideration: M1 was implemented in 2009, restricting the circulation of yellow-labelled vehicles, while M2 was implemented in 2014, restricting the circulation of heavy-duty vehicles. To compare the results of each measure, a time-period when these measures were not applied is used as case-control.
Show more [+] Less [-]Environmental superbugs: The case study of Pedobacter spp Full text
2018
Viana, Ana Teresa | Caetano, Tânia | Covas, Claúdia | Santos, Tiago | Mendo, Sónia
The environment is one of the main reservoirs of antibiotic resistance genes (ARGs) but multidrug resistant (MDR) environmental isolates are barely characterised. As suggested by the name, Pedobacter species have been predominantly isolated from soils, but are also recovered from water (including drinking water), chilled food, fish, compost, sludge, glaciers and other extreme environments. The susceptibility phenotype of Pedobacter lusitanus NL19 (isolated from a deactivated uranium mine), its closely related species and the genus type strain were investigated. All strains are MDR bacteria, resistant to β-lactams, colistin, aminoglycosides and ciprofloxacin. Therefore, Pedobacter spp. are likely intrinsically resistant to β-lactams (including ertapenem) and to other three classes of antibiotics. 6%–8% of their total protein-encoding genes encode a diverse collection of putative ARGs, including β-lactamases. These enzymes are highly abundant in all the other Pedobacter strains with sequenced genomes, especially class C, class B3 and class A. LUS-1 and PLN-1 were further characterised in E. coli. LUS-1 is a class A β-lactamase and it conferred an increase in the MIC of cefotaxime, albeit very low. PLN-1 is a class B3 β-lactamase with carbapenemase activity, conferring resistance to ertapenem and a 66x and 16x increase in the MIC of imipenem and meropenem, respectively. PLN-1 also hydrolyses ampicillin, 1st and 3rd generation cephalosporins, and at a lower extent cephamycins and 4th generation cephalosporins. Therefore, Pedobacter spp. encode a large and diverse arsenal of resistance mechanisms that make them environmental superbugs.
Show more [+] Less [-]Enantioselective toxic effects of cyproconazole enantiomers against Rana nigromaculata Full text
2018
Zhang, Wenjun | Cheng, Cheng | Chen, Li | Deng, Yue | Zhang, Luyao | Li, Yao | Qin, Yinan | Diao, Jinling | Zhou, Zhiqiang
The environmental contaminant, especially pesticides, threatened the amphibian population. In this assay, the enantioselective behavior of cyproconazole on Rana nigromaculata was studied. We found LC50 (lethal concentration causing 50% mortality) of 4-enantiomers was nearly twice as 3-enantiomers in 96 h acute toxicity test. Besides, the significant considerable variation of oxidative stress and LDH (lactic dehydrogenase) induced by the four enantiomers indicated that cyproconazole could enantioselectively affect enzymes in tadpoles. Bioaccumulation experiments showed the order of cyproconazole in the tadpoles was 4-enantiomers>3- enantiomers>2- enantiomers>1- enantiomers during the exposure for 28d. In tissue distribution test, cyproconazole was formed and accumulated in order of 4-enantiomers>2-enantiomers>3- enantiomers>1- enantiomers, except that in the gut. During the elimination experiment, cyproconazole was rapidly eliminated by 95% within the only 24 h. These results suggested that the influence of enantioselective behavior should consider when assessing ecological risk of chiral pesticides to amphibians.
Show more [+] Less [-]Seasonal contribution of assessed sources to submicron and fine particulate matter in a Central European urban area Full text
2018
Samek, Lucyna | Stegowski, Zdzislaw | Styszko, Katarzyna | Furman, Leszek | Fiedor, Joanna
This study presents the air pollution findings of the submicron (PM1) and fine (PM2.5) particulate matter. The submicron particles are entirely absorbed by the human body and they cause the greatest health risk. For the PM2.5 concentration, there are yearly and/or daily limit values regulations by the European Union (EU) and World Health Organization (WHO). There are no such regulations for PM1 but for health risk reason the knowledge of its concentration is important. This paper presents the seasonal concentration contribution of PM1 and PM2.5, their chemical composition and assessed three basic sources. Daily samples of both fractions were collected from 2nd July 2016 to 27th February 2017 in Krakow, Poland. Apart from PM1 and PM2.5 the concentration of 16 elements, 8 ions and BC for each samples were measured. Based on these chemical species the positive matrix factorization (PMF) receptor modeling was used for the determination of three main sources contribution to the PM1 and PM2.5 concentrations. Daily average concentrations of PM2.5 were 12 μg/m3 in summer and 60 μg/m3 in winter. For PM1 it was 6.9 μg/m3 in summer and 17.3 μg/m3 in winter. These data show a significant difference in percentage contribution of PM1 in PM2.5 in summer (58%) and in winter (29%).For the combustion source, the concentrations calculated from PMF modeling in winter were 4.8 μg/m3 for PM1 and 31 μg/m3 for PM2.5. In summer, the concentrations were smaller than 1 μg/m3 for both fractions. Secondary aerosols' concentration for PM1 was 3.4 μg/m3 in summer and 11 μg/m3 in winter - for PM2.5 these were 7.1 μg/m3 and 17 μg/m3 respectively. The third source - soil, industry and traffic together, had small seasonal variation: for PM1 it was from 1.4 to 1.8 μg/m3 and for PM2.5 from 4.7 to 7.9 μg/m3.
Show more [+] Less [-]Potential ecotoxicological effects of elevated bicarbonate ion concentrations on marine organisms Full text
2018
Gim, Byeong-Mo | Hong, Seongjin | Lee, Jung-Suk | Kim, Nam-Hyun | Kwon, Eun-Mi | Gil, Joon-Woo | Lim, Hyun-Hwa | Jeon, Eui-Chan | Khim, Jong Seong
Recently, a novel method for carbon capture and storage has been proposed, which converts gaseous CO2 into aqueous bicarbonate ions (HCO3−), allowing it to be deposited into the ocean. This alkalinization method could be used to dispose large amounts of CO2 without acidifying seawater pH, but there is no information on the potential adverse effects of consequently elevated HCO3− concentrations on marine organisms. In this study, we evaluated the ecotoxicological effects of elevated concentrations of dissolved inorganic carbon (DIC) (max 193 mM) on 10 marine organisms. We found species-specific ecotoxicological effects of elevated DIC on marine organisms, with EC50-DIC (causing 50% inhibition) of 11–85 mM. The tentative criteria for protecting 80% of individuals of marine organisms are suggested to be pH 7.8 and 11 mM DIC, based on acidification data previously documented and alkalinization data newly obtained from this study. Overall, the results of this study are useful for providing baseline information on ecotoxicological effects of elevated DIC on marine organisms. More complementary studies are needed on the alkalinization method to determine DIC effects on seawater chemistry and marine organisms.
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