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Impact of stabilizer on the environmental behavior of PVC films reinforced 1,2,4-triazole moiety
2019
Yousif, Emad | Ahmed, Dina S. | Ahmed, Ahmed | Abdallh, Mustafa | Yusop, Rahimi M. | Mohammed, Salam A.
A new Schiff base containing 1,2,4-triazole ring system (L) was synthesized and confirmed by ¹HNMR, FTIR spectroscopy. The chemical modification of PVC with a new Schiff base (L) was synthesized to produce a homogenous blend (PVC-L). A homogenous blend (PVC-L) was added to copper chloride to produce PVC-L-Cu (II). The PVC films had been irradiated with ultraviolet light for a long period and confirmed by FTIR spectroscopy and weight loss; the surface morphology was inspected by scanning electron microscopy.
Show more [+] Less [-]Persistent and transgenerational effects of risperidone in zebrafish
2019
Kalichak, Fabiana | de Alcantara Barcellos, Heloisa Helena | Idalencio, Renan | Koakoski, Gessi | Soares, Suelen Mendonça | Pompermaier, Aline | Rossini, Mainara | Barcellos, Leonardo José Gil
Since behavior is the connection between the internal physiological processes of an animal and its interaction with the environment, a complete behavioral repertoire is crucial for fish survival and fitness, at both the individual and population levels. Thus, unintended exposure of non-target organisms to antipsychotic residues in the environment can impact their normal behavior, and some of these behavioral changes can be seen during the entire life of the animal and passed to subsequent generations. Although there are some reports related to transgenerational toxicology, little is known of the long-term consequences of exposure to pharmaceutical compounds such as risperidone. Here, we show that zebrafish exposed to risperidone (RISP) during embryonic and larval stages presented impaired anti-predatory behavior during adulthood, characterizing a persistent effect. We also show that some of these behavioral changes are present in the following generation, characterizing a transgenerational effect. This suggests that even short exposures to environmentally relevant concentrations, at essential stages of development, can persist throughout the whole life of the zebrafish, including its offspring. From an environmental perspective, our results suggested possible risks and long-term consequences associated with drug residues in water, which can affect aquatic life and endanger species that depend on appropriate behavioral responses for survival.
Show more [+] Less [-]Effect of pH and citric acid on the growth, arsenic accumulation, and phytochelatin synthesis in Eupatorium cannabinum L., a promising plant for phytostabilization
2019
González, Héctor | Fernández-Fuego, Daniel | Bertrand, Ana | González, Aída
Heavy-metal contamination of soils has increased in the last decades due to anthropogenic and industrial activities. Arsenic is one of the pollutants that is commonly found in industrial soils and is toxic for both plants and humans. The pH of the soil or the culture medium is one of the most important factors that interferes with the bioavailability of this metalloid to the plant. The addition of chelating agents, such as citric acid (CA), can increase the absorption of As by plants. Therefore, the objective of this work is to study the effect of the pH and the exogenous addition of citric acid on the growth, As accumulation, and thiol compounds in Eupatorium cannabinum; this plant grows naturally in contaminated soils in Asturias, Spain, and has a potential use in phytoremediation. The results showed that E. cannabinum was able to tolerate As stress even at extreme pH values and accumulated a high amounts of As in its roots, which makes it a promising species for the phytostabilization of soils polluted with this metalloid. An addition of 20 mg CA L⁻¹ led to increased biomass and As accumulation at acidic pH. In order to determine if thiolic compounds, such as phytochelatins, are involved in As accumulation and detoxification in E. cannabinum, we analyzed the synthesis of these compounds in the presence and absence of As and/or citric acid. Our results suggest that these thiolic compounds play a major role in As detoxification, since the presence of CA as a chelating agent reduced the amount of thiols necessary to cope with the toxicity caused by As.
Show more [+] Less [-]Human health risks assessment for airborne PM10-bound metals in Seoul, Korea
2019
Roy, Debanada | Seo, Yong-Chil | Kim, Seongheon | Oh, Joosung
Seoul, the capital city of South Korea, is the social, political, and economic center of the country. Significant levels of PM₁₀-bound As metalloid and metals have been found in the city, which poses possible adverse health risks to the residents from inhalation exposure. Therefore, this study focuses on the health risk assessment of age-dependent cancer and non-cancer using exposure pathway and human respiratory tract (HRT) mass deposition models. In the case of non-cancer risks, the hazard quotient (HQ) of As via ingestion exposure and the hazard index (HI) was found to be significant (> 1) for the children. The cancer risks through ingestion pathway (CRᵢₙg) were estimated in the order of 10⁻⁴ and 10⁻⁵ for children and adult groups, respectively. The overall CRᵢₙg levels for children were estimated slightly higher than the acceptable level of cancer risk (1 × 10⁻⁴) at all locations throughout the study area. Moreover, the risks of cancer through the inhalation (CRᵢₙₕ) and incremental lifetime cancer risks (ILCR) due to HRT mass deposition were found to be significant (> 10⁻⁶) and with very small discrepancy in risk levels for both age groups. Furthermore, possible sources of the PM₁₀-bound metalloid (As) and metals were predicted through correlation, principal component, and enrichment factor analysis. The results of source apportionment study indicated the local anthropogenic emission sources (vehicular, biomass/coal/oil combustion, industrial), road dust re-suspension, and trans-boundary sources were responsible for the pollution levels in Seoul, South Korea. The health risks can be minimized by reducing the pollution levels of particulate matter at source.
Show more [+] Less [-]Decomposition of passive smoking inequality in Iranian children and adolescents: the CASPIAN-V Study
2019
Rarani, Mostafa Amini | Heshmat, Ramin | Djalalinia, Shirin | Motlagh, Mohammad Esmaeil | Ziaodini, Hasan | Mahdavi-Gorabi, Armita | Taheri, Majzoubeh | Ahadi, Zeinab | Qorbani, Mostafa | Kelishadi, Roya
To investigate the socioeconomic inequality in passive smoking in Iranian children and adolescents. Through a multistage random cluster sampling method, a representative sample of 14,400 school students, aged 6–18 years, were enrolled from urban and rural areas of 30 provinces of Iran. Using a non-linear principal component analysis (NLPCA), the correlated variables were summarized as socioeconomic status (SES). Normalized concentration index (NCI) was used to measure inequality in passive smoking at national and regional SES levels. We decomposed total socioeconomic inequality in passive smoking into explanatory variables to identify the main contributors of inequality in passive smoking in the population studied. Data of 12,327 students and parents were complete for the current study. The response rate was 85.6% (50.9% boys, 71.2% urban residents). About 44% of Iranian students were exposed to passive smoking. The NCI for passive smoking at a national level was − 0.043 (95% confidence interval − 0.035, − 0.012), indicating that passive smoking was more concentrated among poorer children and adolescents. This inequality was statistically significant at a national level and in all regions except for regions with lower middle- and lowest SES levels. Considering the decomposition analysis, the household SES (63%), mothers’ educational level (37%), fathers’ educational level (29%), and school type (18%) made the largest positive contribution to inequality in passive smoking of children and adolescents. Passive smoking was distributed unequally among Iranian children and adolescents; it was more concentrated among socioeconomically disadvantaged families. Public health policies attentions should be given to reduce passive smoking among low SES children and adolescents living with illiterate or low-educated parents.
Show more [+] Less [-]Experimental study of dust deposition settled over tilted PV modules fixed in different directions in the southeast of Iran
2019
Abdolzadeh, Morteza | Nikkhah, Reza
Degradation of photovoltaic system’s power due to dust deposition is one of the important concerns of photovoltaic investors, especially the PV modules which are installed in the hot and dry parts of a country. This issue requires to be more understood and quantify its impact on the PV module performance in installation site. This study experimentally studied the dust deposition using several glasses which were fixed in the wooden frames at different tilt angles and directions in the southeast of Iran. The dust deposition on the glasses, solar energy reduction of the dusty glasses, and PV power reduction due to dust deposition were measured in all months of the year. The results showed that the average dust deposition on the glasses is 4.6 × 10⁻³ gr/m²day during the year. In case of no rain precipitation and no cleaning, this value reached 2.74 × 10⁻²gr/m²day. The percentage of solar energy reduction due to dust deposition was varied between 2 and 16% during the year. A correlation for prediction of the solar energy transmittance reduction based on the settled dust on the glass samples was developed in the studied region using 1-year data collection. The average solar energy reduction was obtained 7% during the year, and this value reached 44% in case of no rain precipitation and no glass cleaning. Results showed that in the most months of the year the wind direction and the direction of the glasses with the maximum dust deposition were coincided with each other. Furthermore, the experimental measurement showed that the calculated optimum monthly tilt angle in some months of the year is not the same with the measured tilt angle due to dust deposition. The difference between the calculated and measured tilt angles in these months was 15°.
Show more [+] Less [-]Uncovering the driving forces of carbon dioxide emissions in Chinese manufacturing industry: An intersectoral analysis
2019
Shi, Yingying | Han, Botang | Zafar, Muhammad Wasif | Wei, Zixiang
As the pillar of national economy, manufacturing industry is the largest primary energy consumer and emitter of carbon dioxide (CO₂) in China. Therefore, capturing the determinants of CO₂ emissions in manufacturing industry is extremely important for national efforts to mitigate carbon emissions. This paper explores the major driving forces behind CO₂ emission changes in China’s manufacturing industry during 2000–2015 from perspectives of the whole sector and 28 subsectors, by applying the temporal logarithmic mean Divisia index (LMDI) method. Moreover, an intersectoral LMDI model is built to uncover the intersectoral discrepancies of CO₂ emissions among 28 subsectors. The temporal analysis indicates that industrial activity and energy intensity are crucial factors respectively contributing to the increase and mitigation of CO₂ emissions. The intersectoral analysis reveals that energy intensity is the dominant factor responsible for the intersectoral discrepancies of CO₂ emissions among 28 subsectors. The great mitigation towards CO₂ emissions can be achieved if energy efficiency is largely improved in carbon-intensive subsectors. Priority should be given by governments to the industrial technology advancement, such as subsidies for energy-saving technological transformation and promotion of international advanced techniques and equipment, which can greatly improve production efficiency and mitigate emissions in manufacturing industry.
Show more [+] Less [-]Phthalates in residential and agricultural soils from an electronic waste-polluted region in South China: distribution, compositional profile and sources
2019
Zhang, Shao-hui | Guo, Ai-jing | Fan, Tong-tong | Zhang, Rong | Niu, Yu-jie
Electronic waste (e-waste) recycling has proven to be a significant source of phthalate (PAE) contamination in the environment. A detailed investigation was conducted to understand the concentration, distribution, profile and possible source of PAEs in residential and agricultural soils from Guiyu, Shantou, China, the largest e-waste processing and recycling areas in the world. Sixteen PAEs were analysed in 46 surface soil samples from three different sampling areas in terms of individual and total concentrations, together with pH and soil organic matter. High concentrations of the total PAEs were found in residential area A (more than 20,000 ng g⁻¹), revealing a clear urban pulse, whereas in residential area B and agricultural areas, concentrations were lower than 10,000 ng g⁻¹. The dominant PAEs were bis (2-nbutoxyethyl) phthalate, bis (4-methyl-2-pentyl) phthalate and dicyclohexyl phthalate. These PAEs were high-molecular weight PAEs (alkyl chains ≥ 6 carbons) and mainly derived from polyvinyl chloride commonly used in electrical and electronic equipment, indicating a distinctive composition in relation to the e-waste area. Three individual and the total PAEs exhibited significant positive correlations with pH. Principal component analysis indicated that PAEs were mainly distributed in three groups according to the alkyl chain length and potential source. This study showed that the informal e-waste recycling has already introduced PAEs into surrounding areas as a pollutant which should draw more attention and regulatory control.
Show more [+] Less [-]Revealing long- and short-run empirical interactions among foreign direct investment, renewable power generation, and CO2 emissions in China
2019
Ahmad, Munir | Zhao, Zhen-Yu | Rehman, Abdul | Shahzād, Muḥammad | Li, Heng
This work systematically examines the empirical interactions among foreign direct investment (FDI), renewable power generation (RPG), hydropower generation (HPG), non-hydropower generation (NHPG), and CO₂ emissions in the long run and short run. To test the existence of long-run equilibrium association among those variables, Bayer-Hanck combined cointegration and autoregressive distributed lag (ARDL) model have been employed on time series of China for the period 1991–2017. The vector error correction model-based short-run impacts among the variables of interest are also estimated. Besides, Toda-Yamamoto causality and Granger causality are employed to confirm the direction of causal links. The existence of a long-run equilibrium relationship is revealed in case of all types of specification. The expansion of both FDI and CO₂ emissions boosted RPG, HPG, and NHPG in the short run and long run, with greater intensity of impacts in the long run. To reflect comparisons, it is found that the renewables generation driving the impact of CO₂ emissions and FDI on NHPG is greater than RPG, which further exceeds HPG. In turn, the RPG, HPG, and NHPG mitigated CO₂ emissions both in the long run and short run, with stronger impacts in the long run. Moreover, the CO₂ emissions inhibition impact of HPG dominated NHPG, which further exceeded that of RPG. The FDI boosted CO₂ emissions in a way that the long-run pollution haven impact is revealed to be powerful than that of the short run. A unidirectional causality has been observed running from FDI to CO₂ emissions, RPG, HPG, and NHPG. A bidirectional causality is found operative between CO₂ emissions and RPG/HPG/NHPG. Interestingly, the long-run and short-run impacts remained homogeneous in terms of directionality. Nevertheless, strict heterogeneity is observed in terms of the degree of impacts. Based on empirics, both long-term and short-term policies on FDI, renewables generation, and CO₂ emissions are vital for decision-makers in China. Graphical abstract
Show more [+] Less [-]Gonadal, body color, and genotoxic alterations in Lithobates catesbeianus tadpoles exposed to nonylphenol
2019
Scaia, María Florencia | de Gregorio, Lara Salgueiro | Franco-Belussi, Lilian | Succi-Domingues, Maysa | de Oliveira, Classius
Endocrine disrupting chemicals are one of the most important factors contributing to worldwide amphibian decline. The 4-nonylphenol (NP) is a degradation product of several compounds, such as detergents and pesticides, affecting the aquatic environment. Here, we test whether treatment with NP has an effect on developing ovarian tissue, nuclear abnormalities in erythrocytes, and body darkness in pre-metamorphic tadpoles of the bullfrog Lithobates catesbeianus. Tadpoles were exposed for 14 days to three different concentrations of NP (1, 10, and 100 μg/L) besides the control group, which was maintained only with water. After determining body coloration, animals were euthanized and gonads and blood were collected and processed for histology and genotoxic analysis. Even though most animals were females, intersex tadpoles were observed in control and treated groups and there were no males in any group. The highest concentration of NP showed an increase in atretic oocytes, but the area corresponding to somatic compartment and early and late germ cells were not affected. Furthermore, all treated groups presented higher amount of nuclear abnormalities in erythrocytes and body darkening when compared with the control group. These results suggest that NP causes genetic damage and morphological alterations in L. catesbeianus tadpoles by disrupting oogenesis, inducing genotoxicity and increasing body coloration. Its effects on gonadal development could cause future impairments in reproduction, while its deleterious effects on genotoxicity and body pigmentation could be used as a biomarker of effect to this compound.
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