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Pinus sylvestris as a bio-indicator of territory pollution from aluminum smelter emissions Texto completo
2017
Kalugina, Olga Vladimirovna | Mikhailova, Tatiana Alekseevna | Shergina, Olga Vladimirovna
The study demonstrates the efficiency of using Pinus sylvestris L. as a bio-indicator of polluting substances that enter the environment with the emission of a large aluminum smelter. Recent research has demonstrated that pollution from aluminum smelter emissions covers a vast territory. The highest content of polluting elements is registered at a distance of 3 km from the smelter, with maximum concentrations found in the industrial zone (0.5 km from the smelter). The farther from the aluminum smelter, the lower the amount of polluting elements in the needles, although the F level still exceeds the background values at a distance of about 60 km from the source, the levels of Zn, Pb, and Cd up to 50 km, S up to 40 km, and Fe and Cu up to 35 km mostly in north-eastern and south-eastern directions correlating with prevailing atmospheric transfer of the emissions. Pollution with polycyclic aromatic hydrocarbons (PAHs) is also most expressed at a distance of 3 km from the smelter, then it gradually decreases to coincide with background concentrations at a distance of more than 60 km. This is confirmed by changes in overall PAH content and in qualitative and quantitative compositions of individual PAHs. The greatest number of components (17 substances) has been found in samples from the territory of the plant area: phenanthrene, fluoranthene, pyrene, chrysene, acenaphthylene, acenaphthene, anthracene, fluorene, benz[а]anthracene, benz[b]fluoranthene, benz[k]fluoranthene, benz[а]pyrene, benz[е]pyrene, perylene, indeno[1,2,3-c,d]pyrene, benz[g,h,i]perylene, and dibenz[a,h]anthracene. The farther away from the plant, the lower the number of components detected in PAH fraction, mainly due to the fact that the concentrations of most toxic PAHs with five or six aromatic rings (benz[b]fluoranthene, benz[k]fluoranthene, benz[а]pyrene, benz[е]pyrene, perylene, indeno[1,2,3-c,d]pyrene, benz[g,h,i]perylene, dibenz[a,h]anthracene) fall below the method detection limit. High concentrations of benz[а]pyrene and perylene in pine needles at the territories adjacent to the aluminum smelter confirm the technogenic character of forest pollution by PAHs.
Mostrar más [+] Menos [-]Characterization of extracellular polymeric substance (EPS) fractions produced by Microcystis aeruginosa under the stress of linoleic acid sustained-release microspheres Texto completo
2017
Ni, Lixiao | Li, Danye | Rong, Shiyi | Su, Lili | Zhou, Wei | Wang, Peifang | Wang, Chao | Li, Shiyin | Acharya, Kumud
This paper focuses on the characterization of extracellular polymeric substances (EPS), which are composed of soluble EPS (SL-EPS), loosely bound EPS (LB-EPS), and tightly bound EPS (TB-EPS) produced by Microcystis aeruginosa under the stress of linoleic acid (LA) and LA sustained-release microspheres. Three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy and Fourier transform infrared (FTIR) spectrometry were used to characterize three forms of EPS while the content of polysaccharide and protein was tested, respectively. The results showed that the highest inhibitor rate (IR) occurred when M. aeruginosa were exposed to LA sustained-release microspheres of 0.3 g L⁻¹. The 3D-EEM contour demonstrated that tryptophan and protein-like substances were detected in all three EPS fractions, whereas humic acid-like substance was only distributed in SL-EPS, and aromatic proteins merely existed in LB-EPS and TB-EPS. The infrared spectrum showed that functional groups in three EPS fractions had no obvious change in all experimental groups. Polysaccharide (1120–1270 cm⁻¹, C–O–C and C–O stretching vibration) and protein (1384–1670 cm⁻¹, C–N and N–H stretching) were detected in three forms of EPS. Graphical abstract ᅟ
Mostrar más [+] Menos [-]Airing ‘clean air’ in Clean India Mission Texto completo
2017
Banerjee, T. | Kumar, M. | Mall, R.K. | Singh, R.S.
The submission explores the possibility of a policy revision for considering clean air quality in recently launched nationwide campaign, Clean India Mission (CIM). Despite of several efforts for improving availability of clean household energy and sanitation facilities, situation remain still depressing as almost half of global population lacks access to clean energy and proper sanitation. Globally, at least 2.5 billion people do not have access to basic sanitation facilities. There are also evidences of 7 million premature deaths by air pollution in year 2012. The situation is even more disastrous for India especially in rural areas. Although, India has reasonably progressed in developing sanitary facilities and disseminating clean fuel to its urban households, the situation in rural areas is still miserable and needs to be reviewed. Several policy interventions and campaigns were made to improve the scenario but outcomes were remarkably poor. Indian census revealed a mere 31% sanitation coverage (in 2011) compared to 22% in 2001 while 60% of population (700 million) still use solid biofuels and traditional cook stoves for household cooking. Further, last decade (2001–2011) witnessed the progress decelerating down with rural households without sanitation facilities increased by 8.3 million while minimum progress has been made in conversion of conventional to modern fuels. To revamp the sanitation coverage, an overambitious nationwide campaign CIM was initiated in 2014 and present submission explores the possibility of including ‘clean air’ considerations within it. The article draws evidence from literatures on scenarios of rural sanitation, energy practises, pollution induced mortality and climatic impacts of air pollution. This subsequently hypothesised with possible modification in available technologies, dissemination modes, financing and implementation for integration of CIM with ‘clean air’ so that access to both sanitation and clean household energy may be effectively addressed.
Mostrar más [+] Menos [-]Periodic characterization of alkyl-naphthalenes in stack gas and ambient air around a medical waste incinerator Texto completo
2017
Adedayo Adesina, Olusola | Ademola Sonibare, Jacob | Diagboya, Paul N. | Adejuwon, Adesuji | Famubode, Temitope | Bello, Josiah O.
Due to the subtle occurrence of environmental polycyclic aromatic hydrocarbon (PAHs) pollution from incinerators, it is seldom considered a significant source of PAH pollution. However, considering the recent build-up of toxics in urban air, this may be a serious concern around the incinerator vicinity due to the potential consequences of PAHs on human health. Hence, this study determined 11 alkyl-naphthalene contributions from a hospital waste incinerator (HWI_0) into ambient air receptor points (HWI_1 to HWI_5) for a 1-year period: June 2014–May 2015. The HWI_0 and ambient gases were sampled using filter-sorbent sampling system and polyurethane foam (PUF) passive samplers, respectively, and all alkyl-naphthalenes were determined using GC-MS. Results showed that the source concentrations were in the range of 0–14.0 ng/m³ and generally higher than the receptor points. The receptor point concentration trends were mainly HWI_1 > HWI_2 ≥ HWI_3 ≥ HWI_5 ≥ HWI_4. Multivariate receptor model analysis suggested high correlations between source and the receptor points though there might be some significant contributions from other emission sources. The average monthly concentrations (∑alkyl-naphthalene) at HWI_0 and the receptors HWI_1, HWI_2, HWI_3, HWI_4 and HWI_5 were 67.4 ± 24.3, 57.9 ± 20.1, 42.8 ± 16.9, 39.7 ± 12.2, 36.5 ± 22.2 and 37.8 ± 15.4 ng/m³, respectively. Though these concentrations were lower than the estimated minimal risk level (MRL) for chronic inhalation exposure to naphthalene and its derivatives 0.003 mg/m³, continuous exposure to these pollutants might result in chronic effects. Finally, this study may be used to evaluate the environmental contribution of alkyl-naphthalenes from typical medical waste incinerator in Nigeria.
Mostrar más [+] Menos [-]Desorption of micropollutant from spent carbon filters used for water purifier Texto completo
2017
Kwon, Da-Sol | Tak, So-Yeon | Lee, Jung-Eun | Kim, Moon-Kyung | Lee, Young Hwa | Han, Doo Won | Kang, Sanghyeon | Zoh, Kyung-Duk
In this study, to examine the accumulated micropollutants in the spent carbon filter used in the water purifier, first, the method to desorb micropollutant from the activated carbon was developed and optimized. Then, using this optimized desorption conditions, we examined which micropollutants exist in spent carbon filters collected from houses in different regions in Korea where water purifiers were used. A total of 11 micropollutants (caffeine (CFF), acetaminophen (ACT), sulfamethazine (SMA), sulfamethoxazole (SMZ), metoprolol (MTP), carbamazepine (CBM), naproxen (NPX), bisphenol-A (BPA), ibuprofen (IBU), diclofenac (DCF), and triclocarban (TCB)) were analyzed using LC/MS-MS from the spent carbon filters. CFF, NPX, and DCF had the highest detection frequencies (>60%) in the carbon filters (n = 100), whereas SMA, SMZ, and MTP were only detected in the carbon filters, but not in the tap waters (n = 25), indicating that these micropollutants, which exist less than the detection limit in tap water, were accumulated in the carbon filters. The regional micropollutant detection patterns in the carbon filters showed higher levels of micropollutants, especially NPX, BPA, IBU, and DCF, in carbon filters collected in the Han River and Nakdong River basins where large cities exist. The levels of micropollutants in the carbon filter were generally lower in the regions where advanced oxidation processes (AOPs) were employed at nearby water treatment plants (WTPs), indicating that AOP process in WTP is quite effective in removing micropollutant. Our results suggest that desorption of micropollutant from the carbon filter used can be a tool to identify micropollutants present in tap water with trace amounts or below the detection limit.
Mostrar más [+] Menos [-]Evaluation of forest structure, biomass and carbon sequestration in subtropical pristine forests of SW China Texto completo
2017
Nizami, Syed Moazzam | Yiping, Zhang | Zheng, Zheng | Zhiyun, Lu | Guoping, Yang | Liqing, Sha
Very old natural forests comprising the species of Fagaceae (Lithocarpus xylocarpus, Castanopsis wattii, Lithocarpus hancei) have been prevailing since years in the Ailaoshan Mountain Nature Reserve (AMNR) SW China. Within these forest trees, density is quite variable. We studied the forest structure, stand dynamics and carbon density at two different sites to know the main factors which drives carbon sequestration process in old forests by considering the following questions: How much is the carbon density in these forest trees of different DBH (diameter at breast height)? How much carbon potential possessed by dominant species of these forests? How vegetation carbon is distributed in these forests? Which species shows high carbon sequestration? What are the physiochemical properties of soil in these forests? Five-year (2005–2010) tree growth data from permanently established plots in the AMNR was analysed for species composition, density, stem diameter (DBH), height and carbon (C) density both in aboveground and belowground vegetation biomass. Our study indicated that among two comparative sites, overall 54 species of 16 different families were present. The stem density, height, C density and soil properties varied significantly with time among the sites showing uneven distribution across the forests. Among the dominant species, L. xylocarpus represents 30% of the total carbon on site 1 while C. wattii represents 50% of the total carbon on site 2. The average C density ranged from 176.35 to 243.97 t C ha⁻¹. The study emphasized that there is generous degree to expand the carbon stocking in this AMNR through scientific management gearing towards conservation of old trees and planting of potentially high carbon sequestering species on good site quality areas.
Mostrar más [+] Menos [-]Effectiveness of SO2 emission control policy on power plants in the Yangtze River Delta, China—post-assessment of the 11th Five-Year Plan Texto completo
2017
Tan, Jiani | Fu, Joshua S. | Huang, Kan | Yang, Cheng-En | Zhuang, Guoshun | Sun, Jian
Facing the air pollution problems in China, emission control strategies have been implemented within the framework of national Five-Year Plan (FYP). According to the lack of post-assessment studies in the literature, this study assessed the effectiveness of the SO₂ emission control policies on power plants after the 11th FYP (2006–2010) by modeling emission control scenarios. The idealized emission control policy (the PS90 scenario with assumption of 90% SO₂ emission reduction from power plants) could reduce the SO₂ and SO₄ ²⁻ concentrations by about 51 and 14%, respectively, over the Yangtze River Delta region. While the actual emission control condition (the P2010 scenario based on the actual emissions from power plants in 2010) demonstrated that the actual reduction benefits were 30% of SO₂ and 9% of SO₄ ²⁻. On the city scale, the P2010 scenario imposed positive benefits on Shanghai, Nanjing, Nantong, and Hangzhou with SO₂ reductions of about 55, 12, 30, and 21%, respectively, while an 11% increase of SO₂ concentration was found in Ningbo. The number of days exceeding China’s National Ambient Air Quality Standard of Class I daily SO₂ concentration was estimated to be 75, 52, 7, 77, and 40 days for Shanghai, Nanjing, Nantong, Ningbo, and Hangzhou under the real SO₂ control condition (P2010). The numbers could be decreased by 16, 11, 2, 21, and 11% if the control effect reaches the level of the PS90 scenario. This study serves as a scientific basis to design capable enforcement of emission control strategies in China in the future national plans.
Mostrar más [+] Menos [-]Cadmium and lead concentrations in hepatic and muscle tissue of demersal fish from three lagoon systems (SE Gulf of California) Texto completo
2017
Gil-Manrique, Brigitte | Nateras-Ramírez, Omar | Martínez-Salcido, Ana I. | Ruelas-Inzunza, Jorge | Páez Osuna, Federico | Amezcua, Felipe
We determined the levels of Cd and Pb in liver and muscle of demersal fish from three lagoon systems (Urías, Huizache, and Teacapán) in the SE Gulf of California with the purpose of comparing the studied metals in fish from the three ecosystems and to assess the potential human health risk. Considering the number of individuals, the sequence of fish abundance was Teacapán > Huizache > Urías. Length and size at maturity of collected species showed that 76.5% of the individuals were juveniles. Overall, Cd and Pb were more accumulated in liver than in muscle. After multivariate analyses, considering fish tissue and locality, Cd and Pb levels were different (p < 0.05) between fish from Teacapán and Huizache. In general, the hazard quotients (HQs) of Pb were higher than the corresponding values of Cd; the highest HQ for Cd (0.0051) corresponded to Mugil curema, and the highest HQ for Pb (0.0099) was estimated in Diapterus peruvianus. With respect to the hazard index (accumulative risk from Cd and Pb), the most elevated value (HI = 0.0124) was estimated for Pomadasys macracanthus. Estimated HI does not represent a health risk at the consumption rates of the Mexican population.
Mostrar más [+] Menos [-]Experimental investigation of performance and emissions of a VCR diesel engine fuelled with n-butanol diesel blends under varying engine parameters Texto completo
2017
Nayyar, Ashish | Sharma, Dilip | Soni, Shyam Lal | Mathur, Alok
The continuous rise in the cost of fossil fuels as well as in environmental pollution has attracted research in the area of clean alternative fuels for improving the performance and emissions of internal combustion (IC) engines. In the present work, n-butanol is treated as a bio-fuel and investigations have been made to evaluate the feasibility of replacing diesel with a suitable n-butanol-diesel blend. In the current research, an experimental investigation was carried out on a variable compression ratio CI engine with n-butanol-diesel blends (10–25% by volume) to determine the optimum blending ratio and optimum operating parameters of the engine for reduced emissions. The best results of performance and emissions were observed for 20% n-butanol-diesel blend (B20) at a higher compression ratio as compared to diesel while keeping the other parameters unchanged. The observed deterioration in engine performance was within tolerable limits. The reductions in smoke, nitrogen oxides (NO ₓ), and carbon monoxide (CO) were observed up to 56.52, 17.19, and 30.43%, respectively, for B20 in comparison to diesel at rated power. However, carbon dioxide (CO₂) and hydrocarbons (HC) were found to be higher by 17.58 and 15.78%, respectively, for B20. It is concluded that n-butanol-diesel blend would be a potential fuel to control emissions from diesel engines. Graphical abstract ᅟ
Mostrar más [+] Menos [-]Morus alba leaf extract mediates neuroprotection against glyphosate-induced toxicity and biochemical alterations in the brain Texto completo
2017
Rebai, Olfa | Belkhir, Manel | Boujelben, Adnen | Fattouch, Sami | Amri, Mohamed
Recent studies demonstrate that glyphosate exposure is associated with oxidative stress and some neurological disorders such as Parkinson’s pathology. Therefore, phytochemicals, in particular phenolic compounds, have attracted increasing attention as potential agents for neuroprotection. In the present study, we investigate the impact of glyphosate on the rat brain following i.p. injection and the possible molecular target of neuroprotective activity of the phenolic fraction from Morus alba leaf extract (MALE) and its ability to reduce oxidative damage in the brain. Wistar rats from 180 to 240 g were i.p. treated with a single dose of glyphosate (100 mg kg⁻¹ b.w.) or MALE (100 μg mL⁻¹ kg⁻¹ b.w.) for 2 weeks. Brain homogenates were used to evaluate neurotoxicity induced by the pesticide. For this, biochemical parameters were measured. Data shows that MALE regulated oxidative stress and counteracted glyphosate-induced deleterious effects and oxidative damage in the brain, as it abrogated LDH, protein carbonyls, and malonyldialdehyde. MALE also appears to be able to scavenge H₂O₂ levels, maintain iron and Ca²⁺ homeostasis, and increase SOD activity. Thus, in vivo results showed that mulberry leaf extract is a potent protector against glyphosate-induced toxicity, and its protective effect could result from synergism or antagonism between the various bioactive phenolic compounds in the acetonic fraction from M. alba leaf extract.
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