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Terpinolene as an enhancer for ultrasonic disinfection of multi-drug-resistant bacteria in hospital wastewater Texte intégral
2022
Mukherjee, Arkadeep | Ahn, Young-Ho
The present study reports for the first time, a novel disinfection method that combines ultrasonication with a natural biocide terpinolene to inhibit tough and opportunistic antimicrobial-resistant (AMR) microorganisms isolated from hospital wastewater treatment plant (HWWTP). The enhancement of the disinfection process was evaluated for the effect of ultrasonication power, operating temperature, and inoculum size. A hybrid methodology combining terpinolene with traditional physico-chemical method of acoustic cavitation delivered efficient disinfection of the secondary effluent of field scale HWWTP, amended with a higher inoculum size of multi-drug-resistant coliform bacteria Enterobactor sp., Citrobacter freundii, and Klebsiella pneumonia. A bacterial load of 6.4 log CFU/mL was completely eliminated in 25 min. The present study also reports that due to the hybrid process, a very small concentration of 0.312 mM (0.25 × Minimum Inhibitory Concentration or MBC) of terpinolene was enough to completely disinfect the multi-drug-resistant coliforms. The leakage of intracellular nucleic acids during the disinfection process suggested disruption of cell membrane as the primary mechanism of disinfection followed by disruption of cellular metabolic function measured by respiratory chain dehydrogenase activity. Moreover, this study is the first to prove that terpinolene remained stable even after the cavitation process, thus revealing possibilities of recycling of the natural compound for wastewater disinfection. The results of the present research suggest that using terpinolene as a bio-additive can efficiently eliminate hazardous multi-drug-resistant bacteria and drastically reduce operational time and cost thus rendering it suitable to replace conventional wastewater disinfection.
Afficher plus [+] Moins [-]A review of plant-based coagulants for turbidity and cyanobacteria blooms removal Texte intégral
2022
El Bouaidi, Widad | Libralato, Giovanni | Douma, Mountasser | Ounas, Abdelaziz | Yaacoubi, Abdelrani | Lofrano, Giusy | Albarano, Luisa | Guida, Marco | Loudiki, Mohammed
In recent years, the proliferation of Harmful Cyanobacterial Blooms (CyanoHABs) has increased with water eutrophication and climate change, impairing human health and the environment in relation to water supply. In drinking water treatment plants (DWTPs), the bio-coagulation based on natural coagulants has been studied as an eco-friendly alternative technology to conventional coagulants for both turbidity and CyanoHABs removal. Plant-based coagulants have demonstrated their coagulation efficiency in turbidity removal, as reported in several papers but its ability in cyanobacterial removal is still limited. This paper mainly reviewed the application of plant-based coagulants in DWTPs, with focus on turbidity removal, including cyanobacterial cells. The future potential uses of these green coagulants to reduce noxious effects of cyanobacterial proliferation are presented. Green coagulants advantages and limitations in DWTPs are reviewed and discussed summarizing more than 10 years of knowledge.
Afficher plus [+] Moins [-]Association between ambient particulate matter (PM2.5/PM10) and first incident ST-elevation myocardial infarction in Suzhou, China Texte intégral
2022
Sun, Qian | Cao, Bangming | Jiang, Yufeng | Zhuang, Jin | Zhang, Chi | Jiang, Bin
Interests in evaluation of the effect of air pollution and weather conditions on cardiovascular disease have increased. However, the relationship between short-term particulate matter (PM) exposure and first incident ST-elevation myocardial infarction (STEMI) remains unclear. Medical records were collected from December 2013 to December 2016. A total of 1354 patients with first incident STEMI were included. The daily average of air pollution and weather conditions were calculated. In this case-crossover study, conditional logistic regression was performed to assess the association between daily concentrations of PM and first incident STEMI. The daily average of PM₂.₅ and PM₁₀ were 58.9 μg/m³ and 80.2 μg/m³, respectively. In this case-crossover study, single-pollutant models showed that each 10 μg/m³ increase in PM₂.₅ was associated with a percent change of 3.36, 95% confidence interval (CI): (1.01–5.77), or in PM₁₀ percent change of 2.1%, 95%CI: (0.2–4.04) for patients with first incident STEMI. The association remained stable after adjusting for ozone (O₃). The results from subgroup analysis showed the association slightly enhanced in women, elder patients, patients with history of diabetes, patients without history of smoking, and cold seasons. The p values were not significant between these strata, which may be due to small sample size. This investigation showed that short-term PM exposure associated with first incident STEMI in Suzhou. Given the effect of PM on the first incident STEMI, strategies to decrease PM should be considered.
Afficher plus [+] Moins [-]Ambient ozone exposure during pregnancy and telomere length in newborns: a prospective investigation in Wuhan, China Texte intégral
2022
Song, Lulu | Wu, Mingyang | Wang, Lulin | Bi, Jianing | Cao, Zhongqiang | Xu, Shunqing | Tian, Yaohua | Xiong, Chao | Wang, Youjie
Recent studies suggest that environmental exposures, including air pollution, may influence initial (newborn) telomere length (TL), which has important implications for lifetime health. However, the effect of prenatal ozone exposure on newborn TL is unclear. This study aimed to examine the association of ozone exposure during pregnancy with newborn TL. We used data from a birth cohort study of 762 mother-newborn pairs performed in Wuhan, China, during 2013–2015. Land-use regression models were used to assess prenatal ozone exposure. Newborn TL was quantified in cord blood by qPCR assay. We applied multiple informant model to explore the relationship of prenatal ozone exposure with newborn TL. After adjustment for potential confounders, an interquartile range (IQR) increase in ozone exposure during the 2nd trimester, 3rd trimester, and whole pregnancy were associated with 6.00% (95% confidence interval [CI]: 1.59%, 10.62%), 12.64% (95% CI: 7.52%, 18.00%), and 7.10% (95% CI: 4.09%, 10.20%) longer cord blood TL, respectively. In contrast, an IQR increase in ozone exposure during the 1st trimester was associated with a 8.39% (95% CI: − 12.90%, − 3.65%) shorter cord blood TL. In multipollutant models, consistent associations were observed between ozone exposures during the 2nd trimester and whole pregnancy and cord blood TL, but not significant for the 1st and 3rd trimesters. In conclusion, our findings suggest positive associations of ozone exposure during the 2nd trimester, 3rd trimester, and whole pregnancy with newborn TL and a negative association during the 1st trimester. This study provides new evidence in humans for a potential “programming” mechanism linking maternal ozone exposure to the initial (newborn) setting of offspring’s telomere biology.
Afficher plus [+] Moins [-]Efficient recovery of rare earth elements from discarded NdFeB magnets by mechanical activation coupled with acid leaching Texte intégral
2022
Mao, Fulin | Zhu, Nengwu | Zhu, Wen | Liu, Bowen | Wu, Pingxiao | Dang, Zhi
Due to the increasing demands and supply shortages for rare earth elements (REEs), the recovery of REEs from discarded NdFeB with high REE content has become extremely important. In this paper, a hydrometallurgical coupling process involving mechanical activation and selective acid leaching was proposed for the recovery of REEs from discarded NdFeB magnets. The effects of ball milling activation speed, hydrochloric acid concentration, and solid–liquid ratio on the leaching efficiencies of REEs in NdFeB magnets were studied. The results indicated that the ball milling activation method could enhance the reactivity of the samples through the action of mechanical force, which promoted the leaching efficiency and leaching speed of REEs. Under the optimum conditions (650-rpm activation speed, 0.4 M hydrochloric acid, 100 g/L solid–liquid ratio), the leaching efficiency of REEs increased up to 99% with low hydrochloric acid consumption and the leaching speed of REEs was triple than that of without activation. The final purity of recovered rare earth oxides reached up to 99.9%. All results demonstrated that ball milling activation coupled with selective leaching of hydrochloric acid could be an effective and environment-friendly strategy to achieve the recovery of REEs.
Afficher plus [+] Moins [-]Analysis of the influencing factors of atmospheric particulate matter accumulation on coniferous species: measurement methods, pollution level, and leaf traits Texte intégral
2022
Zhang, Zhi | Gong, Jialian | Li, Yu | Zhang, Weikang | Zhang, Tong | Meng, Huan | Liu, Xiaowei
Urban trees, especially their leaves, have the potential to capture atmospheric particulate matter (PM) and improve air quality. However, the amount of PM deposited on leaf surfaces detected by different methods varies greatly, and quantitative understanding of the relationship between PM retention capacity and various microstructures of leaf surfaces is still limited. In this study, three measurement methods, including the leaf washing (LW) method, aerosol regeneration (AR) method, and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM–EDX) method, were used to determine the PM retention capacity of leaf surfaces of three coniferous species. Additionally, we analyzed the leaf traits and elemental composition of PM on leaves collected from different sites. The results showed that Pinus tabulaeformis and Abies holophylla were more efficient species in capturing PM than Juniperus chinensis, but different measurement methods could affect the detected results of PM accumulation on leaf surfaces. The concentrations of trace elements accumulated on leaf surfaces differed considerably between different sites. The greatest accumulation of elements that occurred on the leaf surface was at the Shenfu Highway site exposed to high PM pollution levels and the smallest accumulation at the Dongling park site. The stomatal density and contact angle were highly correlated with the PM retention capacity of leaf surfaces of the tested species (Pearson coefficient: r = 0.87, p < 0.01 and r = − 0.70, p < 0.05), while the roughness and groove width were not significantly correlated (Pearson coefficient: r = 0.16 and r = − 0.03). This study suggests that a methodological standardization for measuring PM is urgently required and this could contribute to selecting greening tree species with high air purification capacity.
Afficher plus [+] Moins [-]Assessment and source apportionment of water-soluble heavy metals in road dust of Zhengzhou, China Texte intégral
2022
Faisal, Muhammad | Wu, Zening | Wang, Huiliang | Hussain, Sheikh Zafar | Azam, Muhammad Imran | Muzammil, Muhammad
The water-soluble concentration of heavy metals in road dust poses a considerable hazard to public health. The primary goals of the study were estimation of water-soluble contents of heavy metal, estimation of pollution indices, and source apportionment of water-soluble contents of heavy metals using UNMIX model from the road dust of Zhengzhou city. To accomplish this, inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to determine concentrations of eight heavy metals (Cr, Cu, Ni, Zn, Cd, As, Pb, and Hg), and it has been observed that Cu and Zn were the metals with the highest concentration, while Hg, Cd, and Pb were in the lowest concentration range of metals. Pollution indices, geo-accumulation index (Igₑₒ), contamination factor (CF), and Nemerow synthetic pollution index (PIN) were calculated to assess the contamination level of water-soluble contents of these hazardous heavy metals. Igₑₒ classified the contamination risk into a spectrum of categories ranging from unpolluted (Cr and Pb) to high polluted (Cu and Cd). For the CF results, the concentration of Cr and Pb was found to be low, similar to Igₑₒ, while the concentrations of three heavy metals, Cu, Cd, and Hg, were found to be extremely high or excessive. The results of the PIN assessment indicated that there was an enormous risk of Hg contamination in the city and that Cu, Cd, and Zn were all within a few percent of the Hg pollution level and hence fell into the high pollution group. The UNMIX model was used for source apportionment of dissolved heavy metals and showed: Source 1 (natural sources, 10%), Source 2 (copper mine tailing contamination, 19%), and Source 3 (agricultural activities22%). Source 4 accounted for (air pollution, 15%) of the total and Source 5 accounted for (industrial activity, 34%). It is imperative that immediate and comprehensive pollution control and preventive measures be implemented in the city due to the presence of metal in the dust.
Afficher plus [+] Moins [-]The life expectancy benefits on respiratory diseases gained by reducing the daily concentration of particulate matter to attain different air quality standard targets: findings from a 5-year time-series study in Tianjin, China Texte intégral
2022
Ni, Yang | Zhang, Jimian | Zhang, Mengnan | Bai, Yu | Zeng, Qiang
The short-term effects of particulate matter (PM) on years of life lost (YLL) have been confirmed by several studies; however, little attention has been paid to the effects of PM on life expectancy from respiratory diseases (RD), especially at the city level. A generalized additive model (GAM) was used to assess the associations between daily PM and YLL of the RD and chronic obstructive pulmonary diseases (COPD) in Tianjin from 2015 to 2019. Then the daily avoidable YLL, attributable fraction, and potential life expectancy benefits (PLEB) of RD and COPD by reducing the daily concentration of PM₂.₅ and PM₁₀ to attain the Chinese and World Health Organization (WHO) air quality standard targets were estimated during 2015–2019. The stratified analyses by gender were also conducted. A total of 18279 RD and 7767 COPD deaths were included in this study. Per 10 μg/m³ increments in PM₂.₅ and PM₁₀ at lag1 were significantly associated with 0.83(95%CI: 0.11, 1.55) years and 0.57(95%CI: 0.06, 1.08) years increasing in YLL of total RD and 0.48 (95%CI: 0.07, 0.90) years and 0.30 (95%CI: 0.01, 0.60) years increasing in YLL of total COPD. If the daily PM₂.₅ and PM₁₀ concentrations decreased to attain the Chinese and WHO air quality standard targets, 0.06–0.39 years PLEB due to total RD and 0.08–0.53 years PLEB due to COPD could be gained. And more PLEB on RD could be gained by decreasing the daily PM concentrations to attain the WHO air quality standard targets than that of attaining the Chinese air quality standard targets. These evidence-based findings emphasize the importance of the Chinese PM-related guideline updating and may have implications for PM-related policy-making.
Afficher plus [+] Moins [-]Tailored-designed material for the preconcentration of Cd(II) on glycidyl methacrylate-based ion–imprinted polymer for flame atomic absorption for trace determination in real samples: multivariate optimization Texte intégral
2022
Islam, Aminul | Chauhan, Anjali
A new Cd(II)-imprinting polymer was synthesised based on glycidyl methacrylate (Fe₃O₄@GMA@IIP) and employed to develop a dispersive magnetic solid-phase extraction method for the preconcentration prior to the determination of Cd(II) from the environmental samples. A central composite design (CCD) based on response surface methodology was used for optimization of the process variables and the material shows the promising saturation adsorption capacity of 28.21 mg g⁻¹ under the optimum pH of 4.9 within 15.2 min at saturation concentration 914 μg mL⁻¹. The experimental data were well described by Sips isotherm model and Brouers–Sotolongo fractal kinetic model that indicated the surface heterogeneity and involvement of both chemisorption and physisorption process. Thermodynamic results documented the endothermic and spontaneous nature of adsorption. The sorbent manifest the economic feasibility maintaining its sorption efficiency after the regeneration by 1 M HNO₃ and reusability up to 6 adsorption/desorption cycles. The developed method exhibited the preconcentration factor of 30 and a high degree of tolerance for matrix ions. Limit of detection (LOD) and quantification (LOQ) were calculated as 3.054 and 10.182 μg L⁻¹ respectively. The developed method was validated by the standard reference material and spiking addition method in real samples, and obtained results showed good agreement in accordance with spiking values. The ease of magnetic separation, high selectivity, good adsorption capacity and faster kinetics made this material a promising candidate for Cd(II) determination in various food and aqueous samples.
Afficher plus [+] Moins [-]Traffic pollution tracers in the lymphatic system tissue of children—possible link to chronic tonsillitis development: pilot study Texte intégral
2022
Čabanová, Kristina | Štrbová, Kristína | Motyka, Oldřich | Zeleník, Karol | Dvořáčková, Jana | Zabiegaj, Dominika | Havlíček, Miroslav | Kukutschová, Jana
The origin of metal elements in tonsillar tissues of children patients was investigated in order to establish the link between environmental pollution and tonsilitis diagnosis. The children lived either in a polluted, industrial region (Moravian-Silesian Region, North-East Czechia) or a clean, predominantly agricultural region (South Bohemian Region, South-East Czechia). Simultaneously, the distance of the address of the patients to the closest main road was assessed. The elemental content of the present particulate matter in the tonsil samples, coming from indicated tonsillectomies, was analysed using scanning electron microscopy equipped with an X-ray microprobe. No significant association of the elemental composition and the region was found using both bivariate and multivariate methods; however, an association with the distance to the closest main road was found. The study presents a novel assessment of the tonsillar tissues and supports the link between environmental factors (traffic-related particulate pollution) and the onset of chronic, idiopathic diseases in children, which has been debated recently.
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