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Effects of biochar underwent different aging processes on soil properties and Cd passivation Full text
2022
Qu, Juanjuan | Zhang, Xu | Guan, Qingkai | Kong, Linghui | Yang, Rui | Ma, Xianfa
This study aims to determine the efficacy of biochar underwent different aging process including freeze-thaw cycling aging (FB), acidified aging (AB), and microbial aging (MB) on soil physicochemical properties and Cd passivation. The Cd-contaminated soil (3 mg·kg⁻¹) amended with the three kinds of aging biochar (at 4% w:w) were subjected to 56-day incubation. The application of FB and MB in soil increased the soil pH (0.82–1.04, 0.27–9.36), CEC (1.06–2.53 cmol·kg⁻¹, 1.66–2.59 cmol·kg⁻¹), and organic matter content (2.28–4.67 g·kg⁻¹, 3.70–5.48 g·kg⁻¹). FB performed best in stabilizing Cd (17.06–23.65%). On the contrary, AB decreased the soil pH and CEC by 0.82–1.04 and 1.32–2.40 cmol·kg⁻¹ and activated Cd by 11.6–19.24%. In conclusion, the efficacy of biochar on soil remediation and Cd passivation varied with aging method and cycle, and freeze-thaw treatment is an effective approach to improve the performance of biochar.
Show more [+] Less [-]A bibliometric analysis on the research trends of climate change effects on economic vulnerability Full text
2022
Islam, Md Mahfuzul | Chowdhury, Mohammad Abdul Matin | Begum, Rawshan Ara | Amir, Ahmad Aldrie
The climate change effect has received a crucial concern from global policymakers as well as academic researchers. The climate change effect is a real-world issue threatening the existence of species and human beings, thus causing the economic vulnerability. Apart from policymakers, academic researchers are showing their concern on the effect of climate change on economic and socioeconomic vulnerability through publishing research articles in the recent decade. In light of the revolution of research articles, this study applied a bibliometric analysis on the academic research articles to explore the publication trends, themes, impacts, and potential scopes for further studies. Both the Scopus and the Web of Science online databases were used to search for journal articles linked to climate change effects and economic vulnerability. The final data of 229 journal articles were analyzed using bibliometric and visualization tools “Biblioshiny” and “VOSViewer.” The findings unveiled an uprising trend in publications and posited several themes, mainly exposure, sensitivity, drought, and flood by means of climate change effects that affect economic vulnerability. Based on the findings and review of literature, several research gaps were identified and offered opportunities for further studies. The policymakers can attribute attention to encouraging more research in several areas in addition to agriculture and coastal regions.
Show more [+] Less [-]Phytoremediation of nitrate contamination using two halophytic species, Portulaca oleracea and Salicornia europaea Full text
2022
Mohammadzadeh, Parviz | Hajiboland, Roghieh
Nitrate is a common form of nitrogen fertilizer, and its excess application combined with easy leaching from agricultural fields causes water and soil contamination, hazards on human health, and eutrophication of aquatic ecosystems. Compared to other pollutants, the application of phytoremediation technology for nitrate-contaminated sites has received less attention. Nitrophilous halophyte species are suitable candidates for this purpose particularly by application of additional treatments for assisting nitrate accumulation. In this work, two annual halophyte species, Portulaca oleracea and Salicornia europaea were studied for their phytoremediation capacity of nitrate-contaminated water and soils. Plants were treated with three nitrate levels (2, 14, and 50 mM) combined with either selenium (10 µM as Na₂SeO₄) or salt (100 mM NaCl) in the hydroponics and sand culture medium, respectively. A fast growth and production of higher biomass enables P. oleracea for higher nitrate removal compared with S. europaea in both experiments. In S. europaea, both selenium and salt treatments enhanced nitrate removal competence through increasing the biomass and nitrate uptake or assimilation capacity. Salt treatment, however, reduced these parameters in P. oleracea. Based on data, selenium-assisted phytoremediation of nitrate contamination is a feasible strategy for both species and S. europaea is better suited to nitrate-contaminated saline water and soils. Nitrate accumulation in both species, however, exceeds that of the permitted nitrate level in the forage crops suggesting that the phytoremediation byproducts could not be consumed and other management strategies should be applied to the residual biomass.
Show more [+] Less [-]Phthalic acid esters (PAEs) in workplace and house dust from Vietnam: concentrations, profiles, emission sources, and exposure risk Full text
2022
Hoang, Anh Quoc | Le, Thuy Minh | Nguyen, Ha My Nu | Le, Huong Quang | Vu, Nam Duc | Chu, Ngọc Châu | Dang, Giang Huong Minh | Minh, Tu Binh | Takahashi, Shin | Tran, Tri Manh
The occurrence of nine phthalic acid esters (PAEs) were determined in indoor dust samples collected from vehicle repair shops, waste processing workshops, and homes in Vietnam. Concentrations of total PAEs ranged from 585 to 153,000 (median 33,400 ng/g), which fall in the lower end of global range. The PAE levels in workplace dust (median 49,100; range 9210–153,000 ng/g) were significantly higher than those in house dust (median 23,700; range 585–83,700 ng/g), indicating waste processing activities as potential PAE sources. The most predominant compound was di-(2-ethyl)hexyl phthalate (DEHP), accounting for 62 ± 18% of total PAEs. Other major compounds were benzyl butyl phthalate (BzBP) (10 ± 12%), di-n-butyl phthalate (DnBP) (9.7 ± 7.7%), di-n-octyl phthalate (DnOP) (7.9 ± 8.1%), and diisobutyl phthalate (DiBP) (6.9 ± 5.0%). Proportions of BzBP and DnBP in some workplace dust samples were markedly greater than in common house dust, suggesting specific emission sources. Daily intake doses of selected PAEs (e.g., DnBP, DiBP, BzBP, and DEHP) through dust ingestion were much lower than reference doses, implying acceptable levels of risk.
Show more [+] Less [-]Health impact assessment of auto rickshaw and cab drivers due to exposure to vehicular pollution in Delhi: an integrated approach Full text
2022
Jain, Suresh | Barthwal, Vaishnavi
Vehicular emission is an important contributor to air pollution in the urban environment and impacts the health of commuters as well as drivers. The in-vehicle concentration of pollutants is known to be higher than the ambient environment and varies with the mode of transport. Thus, this study attempts to assess the health impacts of air pollution exposure on auto rickshaws and cab drivers. The study was conducted in Delhi using a triangular approach involving a health perception survey, lung function test and in-vehicle monitoring of particulate matter (PM₁, PM₂.₅, PM₁₀) concentration to assess the health impacts of air pollution on auto rickshaw and cab drivers. A total of 150 respondents (75 from each occupation) were surveyed, and spirometry was performed for 40 respondents (20 from each occupation). Binary logistic regression showed auto rickshaw drivers were exposed to significantly higher in-vehicle PM concentrations in summers and winters and, thus, had a significantly higher risk of developing respiratory, ophthalmic and dermatological health symptoms (p< 0.05 and relative risk >1). Pulmonary function test showed obstructive lung impairment was reported only among auto rickshaw drivers (6%) and restrictive lung impairment was also more prevalent among auto rickshaw drivers (48%) than cab drivers (33%), suggesting a greater vulnerability of auto rickshaw drivers to respiratory health issues. Lung function impairment was associated with age (p= 0.002). The health and well-being of individuals is a matter of global concern, also highlighted in sustainable development goal no. 3. However, it was observed that neither auto rickshaw drivers nor cab drivers used formal/standard protective measures mainly due to unawareness or unaffordability. The study suggests increasing awareness and formulating guidelines to highlight the use of proper protective measures by these vulnerable groups and specific policy measures to protect outdoor workers like auto rickshaw drivers.
Show more [+] Less [-]Challenges and opportunities for drinking water treatment residuals (DWTRs) in metal-rich areas: an integrated approach Full text
2022
Briso, Alejandro | Vega, Alejandra S. | Molinos-Senante, María | Pastén, Pablo
The physicochemistry and production rate of drinking water treatment residuals (DWTRs) depends on the raw water composition and the plant operational parameters. DWTRs usually contain Fe and/or Al oxyhydroxides, sand, clay, organic matter, and other compounds such as metal(oids), which are relevant in mining countries. This work proposes a simple approach to identify DWTRs reuse opportunities and threats, relevant for public policies in countries with diverse geochemical conditions. Raw water pollution indexes and compositions of DWTRs were estimated for Chile as a model case. About 23% of the raw drinking water sources had moderate or seriously contamination from high turbidity and metal(loid) pollution If the untapped reactivity of clean DWRTs was used to treat resources water in the same water company, the 73 and 64% of these companies would be able to treat water sources with As and Cu above the drinking water regulations, respectively. Integrating plant operational data and the hydrochemical characteristics of raw waters allows the prediction of DWTRs production, chemical composition, and reactivity, which is necessary to identify challenges and opportunities for DWTRs management.
Show more [+] Less [-]Cumulative Ordinary Kriging interpolation model to forecast radioactive fallout, and its application to Chernobyl and Fukushima assessment: a new method and mini review Full text
2022
Külahcı, Fatih | Şen, Zekâi
The Cumulative Ordinary Kriging (COK) interpolation method has been proposed for the spatial prediction of atmospheric radioactive fallout in any given region. COK is built on the Ordinary Kriging and Cumulative Semivariogram methods and combines all their advantages to achieve statistically significant results. It is verified in this paper the reliability of the results from COK with other well-known Modified Shepard’s Method (MSM), Inverse Distance Square (INDSQ), Polynomial Regression (PR), Natural Neighbour (NN), Radial Basis (RB), and Kriging Method interpolation methods. The model is tested in detail and in every possible way in two and three dimensions and applied to real-time Cs-134 and Cs-137 radioactive fallout data from the Chernobyl and Fukushima reactor accidents by combining both experimental and theoretical results. The results obtained from the applications for all interpolation methods are included in the supplementary materials section at the end of the article for the benefit of the readers. COK can also be used for spatial modelling of any particle at micro or macro scale. It can contribute significantly to environmental quality, ecological, and human health.
Show more [+] Less [-]Treatment technologies for bakers’ yeast production wastewater Full text
2022
Igwegbe, Chinenye Adaobi | Obiora-Okafo, Ifeoma Amaoge | Iwuozor, Kingsley O. | Ghosh, Soumya | Kurniawan, Setyo Budi | Selvasembian, Rangabhashiyam | Kanaoujiya, Rahul | Ighalo, Joshua O.
Researchers in recent years have utilized a broad spectrum of treatment technologies in treating bakers’ yeast production wastewater. This paper aims to review the treatment technologies for the wastewater, compare the process technologies, discuss recent innovations, and propose future perspectives in the research area. The review observed that nanofiltration was the most effective membrane process for the treatment of the effluent (at >95% pollutant rejection). Other separation processes like adsorption and distillation had technical challenges of desorption, a poor fit for high pollutant load and cost limitations. Chemical treatment processes have varying levels of success but they are expensive and produce toxic sludge. Sludge production would be a hurdle when product recovery and reuse are targeted. It is difficult to make an outright choice of the best process for treating the effluent because each has its merits and demerits and an appropriate choice can be made when all factors are duly considered. The process intensification of the industrial-scale production of the bakers’ yeast process will be a very direct approach, where the process optimisation, zero effluent discharge, and enhanced recovery of value-added product from the waste streams are important approaches that need to be taken into account.
Show more [+] Less [-]High-normal blood pressure (prehypertension) is associated with PM2.5 exposure in young adults Full text
2022
Ye, Huaze | Tang, Jie | Luo, Leiqin | Yang, Tianjian | Fan, Kedi | Xu, Long
We aimed to examine PM₂.₅ exposure, blood pressure (SBP and DBP) measurement, and hypertension risk factors and to assess the association between PM₂.₅ exposure and hypertension among young adults. The mean SBP was 117.78 mmHg, with 11.22% high-normal blood pressure (prehypertension) and 2.51% hypertension (≥ 140 mmHg). DBP was 75.48 mmHg with 26.37% prehypertension and 4.53% hypertension (≥ 90 mmHg). The median PM₂.₅ in the past year was 31.79 μg/m³, with highest in winter (49.33 μg/m³), followed by spring (37.34 μg/m³), autumn (29.64 μg/m³), and summer (24.33 μg/m³). Blood pressure was positively correlated with age, height, weight, BMI, daily smoking, alcohol consumption, mental stress, and staying up in the past 1 year, and negatively with season-specific temperature. After adjustment for the covariates, each 10 μg/m³ increase in PM₂.₅ was associated with SBP (day 1 = 1.07 mmHg, day 3 = 1.25 mmHg, day 5 = 1.01 mmHg) and DBP (day 1 = 1.06 mmHg, day 3 = 1.28 mmHg, day 5 = 1.29 mmHg, day 15 = 0.87 mmHg, day 30 = 0.56 mmHg). Exposure in winter and the past year was associated with 1.21 mmHg and 0.95 increase mmHg in SBP, respectively. Logistic models showed for every 1 μg/m³ increase of PM₂.₅, SBP in day 1 and day 5 was increased by 6% and 4%, and DPB by 3% and 16%, respectively. SBP was increased by 8% in spring and 19% in winter, and DBP was increased by 7% in winter. Our data suggest a certain prevalence of pre- or hypertension among young population, which is associated with short-term fluctuation and season-specific exposure of PM₂.₅.
Show more [+] Less [-]Comparing the effects of calcium and magnesium ions on accumulation and translocation of cadmium in rice Full text
2022
Li, Xiangying | Teng, Lang | Fu, Tianling | He, Tengbing | Wu, Pan
Rice (Oryza sativa L.) is one of China’s most important food crops, and it is considered the primary source of human exposure to cadmium (Cd) pollution. Adding calcium (Ca) and magnesium (Mg) to the plant nutrient solutions reduces the accumulation of Cd in the rice, but under the same condition, which one has the better effect remains unclear. Thus, hydroponic experiments were performed to compare the effects of Ca and Mg ions with concentration gradients (0.10, 0.25, and 0.50 g/L, respectively) on the absorption, distribution, and translocation of Cd in rice. The Cd contents of roots, stems, leaves, panicles, husks, and grains in different growth stages were determined. The results revealed that the supplementation of both Ca and Mg influenced the Cd accumulation and translocation in rice tissues. The Cd concentrations of different patterns were in the following order: roots > stems > leaves ≈ panicles ≈ husks > grains. Both of Ca and Mg had an apparent antagonism with Cd in different parts of the rice plant, and the antagonism was more obvious in the high Cd stress treatments. With the addition of 0.1 g/L Ca²⁺ and Mg²⁺ ions, the grain Cd contents increased, while the application of 0.25 and 0.5 g/L Ca²⁺ and Mg²⁺ ions reduced grains Cd by 19.08–38.99%, with the average value of 26.75%. Under the same concentrations, the grain Cd content of Ca treatments was lower than that of Mg treatments by 8.74%. In the Ca (Mg)-deficient and Ca (Mg)-sufficient conditions, the husks and panicles accumulated Cd to hinder Cd translocation, respectively. Altogether, the results of this study indicated that Ca had a greater effect for decreasing rice Cd accumulation and translocation than Mg, and the panicle and husk were the important parts for reducing Cd translocation to grain, and these might be a focal point for the future research. It was possible to plant and grow rice in Cd-polluted soil and that the accumulation and translocation of Cd in rice plants could be reduced by optimizing soil nutrient elements.
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