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A consumption value-gap analysis for sustainable consumption Texto completo
2017
Biswas, Aindrila
Recent studies on consumption behavior have depicted environmental apprehension resulting from across wide consumer segments. However, this has not been widely reflected upon the growth in the market shares for green or environment-friendly products mostly because gaps exist between consumers’ expectations and perceptions for those products. Previous studies have highlighted the impact of perceived value on potential demand, consumer satisfaction and behavioral intentions. The necessity to understand the effects of gaps in expected and perceived values on consumers’ behavioral intention and potential demand for green products cannot be undermined as it shapes the consumers’ inclination to repeated purchase and consumption and thus foster potential market demand. Pertaining to this reason, the study aims to adopt a consumption value-gap model based on the theory of consumption values to assess their impact on sustainable consumption behavior and market demand of green products. Consumption value refers to the level of fulfillment of consumer needs by assessment of net utility derived after effective comparison between the benefits (financial or emotional) and the gives (money, time, or energy). The larger the gaps the higher will be the adversarial impact on behavioral intentions. A structural equation modeling was applied to assess data collected through questionnaire survey. The results indicate that functional value-gap and environmental value-gap has the most adversarial impact on sustainable consumption behavior and market demand for green products.
Mostrar más [+] Menos [-]Cytotoxic effects of seven Tunisian hospital wastewaters on the proliferation of human breast cancer cell line MDA-231: correlation with their chemical characterization Texto completo
2017
Nasri, Emna | Machreki, Monia | Beltifa, Asma | Aroui, Sonia | Ghorbel, Asma | Saad, Amina | Feriani, Anouar | Borgi, Mohamed Ali | Ghazouani, Lakhdar | Sire, Olivier | Balcázar, José Luis | Mansour, Hedi Ben
Hospital wastewaters contain large amounts of pharmaceutical residues, which may eventually be discharged into the aquatic environment through wastewater treatment plants, raising the question of their impact on human and environmental health. This has prompted the launch of several monitoring studies into the most commonly administered compounds in urban wastewater. The aim of this study was, therefore, to explore the cytotoxic potential of wastewaters samples collected from seven hospitals in Tunisia. The physicochemical analyses showed a large fluctuation of certain parameters in the collected samples, such as chemical oxygen demand (ranged from 860 to 1720 mg L⁻¹), biochemical oxygen demand (ranged from 385 to 747 mg L⁻¹), total organic carbon (ranged from 256 to 562 g L⁻¹), total suspended solids (ranged from 905 to 1450 mg L⁻¹), conductivity (ranged from 3.31 to 7.14 μsm/cm), and turbidity (ranged from 100 to 480 NTU). The analysis using inductively coupled plasma mass spectrometry (ICP-MS) also showed that hospital wastewater contains high concentrations of Hg (ranged from 0.0024 to 0.019 mg L⁻¹). This could be explained by the variation of the activity and the services in certain hospitals compared to others. All hospital wastewater samples induced the proliferation of human breast cancer cell line MDA-231, even at low concentrations (20 μL/assay). Moreover, the maximum induction reached at the concentration of 60 μL/assay in wastewater samples from hospitals located in Monastir, Sidi Bouzid, Mahdia, and Sfax with percentages of induction up to 42.33, 14, 7.61, and 5.42%, respectively. These observations could be due to the presence of endocrine disrupting compounds (EDCs) in these wastewaters. Given this, our results evidenced the potential risk of these hospital effluents to environmental and public health.
Mostrar más [+] Menos [-]Dental enamel as biomarker for environmental contaminants in relevant industrialized estuary areas in São Paulo, Brazil Texto completo
2017
de Oliveira, Vera Lucia Ferreira | Gerlach, Raquel Fernanda | Martins, Lourdes Conceição | de Souza Guerra, Carolina | Frazão, Paulo | Braga, Alfésio Luis Ferreira | Pereira, Luiz Alberto Amador
Heavy metal contamination is a long-standing and very well-known public health problem, and its exposure can cause damage to several organs of human body, especially on the central nervous system of young children and teenagers. The aim of this article is to evaluate lead, cadmium, and manganese contamination in 125 children from 6 to 13 years old living in contaminated areas during the period from 2006 to 2009 (São Vicente, Cubatão Downtown, Bertioga and Cubatão Pilões/Água Fria). This estuary area is the most important example of environmental degradation by chemicals from industrial sources. This is a cross-sectional study through clinical examinations and dental enamel tests. All mothers from these children lived in the area since before the pregnancy. Lead, cadmium, and manganese levels (μg/g) were measured on dental enamel samples through graphite furnace atomic absorption spectrometry, searching for the occurrence of heavy metals. The mean lead concentrations were 139.48 μg/g in Cubatão Pilões/Água Fria, 170.45 μg/g in Cubatão Downtown, 213.52 μg/g in São Vicente, and 151.89 μg/g in Bertioga. The mean cadmium concentrations were 10.83 μg/g in Cubatão Pilões/Água Fria, 12.58 μg/g in Cubatão Downtown, 10.92 μg/g in São Vicente, and 14.57 μg/g in Bertioga. The mean manganese concentrations were 23.49 μg/g in Cubatão Pilões/Água Fria, 30.90 μg/g in Cubatão Downtown, 41.46 μg/g in São Vicente, and 42.00 μg/g in Bertioga. Dental surface enamel may be used as an efficient biomarker of past environmental exposure to lead, manganese, and cadmium which are associated to well-known sources of heavy metal contamination. The results suggest that the evaluated children were exposed to sources of lead, cadmium, and manganese since before their conceptions. Although Bertioga initially was chosen as a control area of this study, it was also was verified to have heavy metal contamination on examined children.
Mostrar más [+] Menos [-]Citrus stand ages regulate the fraction alteration of soil organic carbon under a citrus/Stropharua rugodo-annulata intercropping system in the Three Gorges Reservoir area, China Texto completo
2017
Zhang, Yang | Ni, Jiupai | Yang, John | Zhang, Tong | Xie, Deti
Soil carbon fractionation is a valuable indicator in assessing stabilization of soil organic matter and soil quality. However, limited studies have addressed how different vegetation stand ages under intercropping agroforestry systems, could affect organic carbon (OC) accumulation in bulk soil and its physical fractions. A field study thus investigated the impact of citrus plantation age (15-, 25-, and 45-year citrus) on the bulk soil organic carbon (SOC) and SOC fractions and yields of Stropharia rugoso-annulata (SRA) in the Three Gorges Reservoir area, Chongqing, China. Results indicated that the intercropping practice of SRA with citrus significantly increased the SOC by 57.4–61.6% in topsoil (0–10 cm) and by 24.8–39.9% in subsoil (10–30 cm). With a significantly higher enhancement under the 25-year citrus stand than the other two stands, all these citrus stands of three ages also resulted in a significant increase of free particulate OC (fPOC, 60.1–62.4% in topsoil and 34.8–46.7% in subsoil), intra-micro aggregate particulate OC (iPOC, 167.6–206.0% in topsoil and 2.77–61.09% in subsoil), and mineral-associated OC (MOC, 43.6–46.5% in topsoil and 26.0–51.5% in subsoil). However, there were no significant differences in yields of SRA under three citrus stands. Our results demonstrated that citrus stand ages did play an important role in soil carbon sequestration and fractionation under a citrus/SRA intercropping system, which could therefore provide a sustainable agroforestry system to enhance concurrently the SOC accumulation while mitigating farmland CO₂ emission.
Mostrar más [+] Menos [-]Highly efficient biosorptive removal of lead from industrial effluent Texto completo
2017
Sao, Kajal | Pandey, Madhurima | Pandey, Piyush Kant | Khan, Fahmida
This study has been focused on the efficient removal of Pb (II) from contaminated waters by biosorption using plant derived material. Accordingly an indigenous shrub, Tinospora cordifolia has been identified as the most suitable biosorbent. The plant biomass was subjected to optimization of various parameters such as the pH, equilibrium time, dosage, concentration, temperature and the applicable adsorption models. The optimum pH identified was 4.0 with a contact time of 60 min at room temperature (27 ± 2 °C). The experimental data fitted well to adsorption isotherms and the uptake capacity of Pb (II) was found to be 20.83 and 63.77 mg/g in batch mode and column mode, respectively. The high correlation factors obtained for Langmuir and Freundlich models indicated that both models were obeyed by the system. Kinetic study for adsorption of Pb (II) follow only pseudo second order rate of reaction. The accumulation of lead in biomass was confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. The FTIR analysis indicated the involvement of hydroxyl (−OH), alkenes (=CH) and carbonyl group (C = O) chelates in metal binding. The SEM and EDX analysis showed the structural changes and the filling of voids in the biomass thus, it indicated the metal-binding mechanism. In elution studies, the 0.1 M Na₂CO₃ was found to be the best with about 71% elution of the adsorbed metal. The biomass was then used for the removal of Pb (II) in synthetic and real wastewater samples from a lead-acid battery industry. It is also noteworthy that even at a very high concentration of 450 mg/L, the biomass was showing about 92% removal. The result is to establish the efficacy of T. cordifolia as a very good bioadsorbent for the Pb (II) removal from contaminated water.
Mostrar más [+] Menos [-]Recycling of palm oil industrial wastes using vermicomposting technology: its kinetics study and environmental application Texto completo
2017
Rupani, Parveen Fatemeh | Embrandiri, Asha | Ibrahim, Mahamad Hakimi | Shahadat, Mohammad | Hansen, Sune Balle | Ismail, Sultan Ahmed | Ab. Kadir, Mohd Omar
The present paper reports management of palm oil mill effluent (POME) mixed with palm-pressed fibre (PPF) POME-PPF mixture using eco-friendly, cost-effective vermicomposting technology. Vermicomposting of POME-PPF was performed to examine the optimal POME-PPF ratio with respect to the criteria of earthworm biomass and to evaluate the decomposition of carbon and nitrogen in different percentages of POME-PPF mixtures. Chemical parameters such as TOC, N, P and K contents were determined to achieve optimal decomposition of POME-PPF. On this basis, the obtained data of 50% POME-PPF mixture demonstrated more significant results throughout the experiment after addition of the earthworms. However, 60 and 70% mixtures found significant only in the last stages of the vermicomposting process. The decomposition rate in terms of -ln (CNₜ/CNₒ) showed that the 50% mixture has higher decomposition rate as compared to the 60 and 70% (k50% = 0.0498 day⁻¹). The vermicomposting extracts (50, 60 and 70%) of POME-PPF mixtures were also tested to examine the growth of mung bean (Vigna radiata). It was found that among different extract dilutions, 50% POME-PPF vermicompost extract provided longer root and shoot length of mung bean. The present study concluded that the 50% mixture of POME-PPF could be chosen as the optimal mixture for vermicomposting in terms of both decomposition rate and fertilizer value of the final compost. Graphical abstract ᅟ
Mostrar más [+] Menos [-]Causality links among renewable energy consumption, CO2 emissions, and economic growth in Africa: evidence from a panel ARDL-PMG approach Texto completo
2017
Attiaoui, Imed | Toumi, Hassen | Ammouri, Bilel | Gargouri, Ilhem
This research examines the causality (For the remainder of the paper, the notion of causality refers to Granger causality.) links among renewable energy consumption (REC), CO₂ emissions (CE), non-renewable energy consumption (NREC), and economic growth (GDP) using an autoregressive distributed lag model based on the pooled mean group estimation (ARDL-PMG) and applying Granger causality tests for a panel consisting of 22 African countries for the period between 1990 and 2011. There is unidirectional and irreversible short-run causality from CE to GDP. The causal direction between CE and REC is unobservable over the short-term. Moreover, we find unidirectional, short-run causality from REC to GDP. When testing per pair of variables, there are short-run bidirectional causalities among REC, CE, and GDP. However, if we add CE to the variables REC and NREC, the causality to GDP is observable, and causality from the pair REC and NREC to economic growth is neutral. Likewise, if we add NREC to the variables GDP and REC, there is causality. There are bidirectional long-run causalities among REC, CE, and GDP, which supports the feedback assumption. Causality from GDP to REC is not strong for the panel. If we test per pair of variables, the strong causality from GDP and CE to REC is neutral. The long-run PMG estimates show that NREC and gross domestic product increase CE, whereas REC decreases CE.
Mostrar más [+] Menos [-]Effect of soil contamination with fluorine on the yield and content of nitrogen forms in the biomass of crops Texto completo
2017
Szostek, Radosław | Ciećko, Zdzisław
The research was based on a pot experiment, in which the response of eight species of crops to soil contamination with fluorine was investigated. In parallel, some inactivating substances were tested in terms of their potential use for the neutralization of the harmful influence of fluorine on plants. The response of crops to soil contamination with fluorine was assessed according to the volume of biomass produced by aerial organs and roots as well as their content of N-total, N-protein, and N-NO₃ ⁻. The following crops were tested: maize, yellow lupine, winter oilseed rape, spring triticale, narrow-leaf lupine, black radish, phacelia, and lucerne. In most cases, soil pollution with fluorine stimulated the volume of biomass produced by the plants. The exceptions included grain and straw of spring triticale, maize roots, and aerial parts of lucerne, where the volume of harvested biomass was smaller in treatments with fluorine-polluted soil. Among the eight plant species, lucerne was most sensitive to the pollution despite smaller doses of fluorine in treatments with this plant. The other species were more tolerant to elevated concentrations of fluorine in soil. In most of the tested plants, the analyzed organs contained more total nitrogen, especially aerial organs and roots of black radish, grain and straw of spring triticale, and aerial biomass of lucerne. A decrease in the total nitrogen content due to soil contamination with fluorine was detected only in the aerial mass of yellow lupine. With respect to protein nitrogen, its increase in response to fluorine as a soil pollutant was found in grain of spring triticale and roots of black radish, whereas the aerial biomass of winter oilseed rape contained less of this nutrient. Among the analyzed neutralizing substances, lime most effectively alleviated the negative effect of soil pollution with fluorine. The second most effective substance was loam, while charcoal was the least effective in this respect. Our results showed the effect of soil contamination with fluorine on the yield and chemical composition of fluorine depended on the species and organ of a tested plant, on the rate of the xenobotic element and on the substance added to soil in order to neutralize fluorine.
Mostrar más [+] Menos [-]Public exposure to radioactivity levels in the Lebanese environment Texto completo
2017
El Samad, O. | Baydoun, R. | Aoun, M. | Zaidan, W. | El Jeaid, H.
In the framework of a National Environmental Radiation Survey Program, a total of 950 samples were collected and analyzed over 7 years. The program covers different compartment of Lebanese environment, rivers, wells, marine samples, soil, and foodstuff. Air was monitored continuously through a radiation early warning network system. Data collected from 2009 to 2015 are presented in this work. Gross alpha/gross beta values in well samples were below the guidance levels stated by the WHO. Cesium-137 was detected in milk samples, whey, and jam. However, its content was much lower than the national permissible level, while its activity concentration in marine samples was lower than the values reported in studies carried out in the Mediterranean Sea. The activity concentration of ⁴⁰K in food samples was comparable to studies carried out in neighboring countries and higher than the content determined in non Mediterranean countries. Concerning marine environment, the activity concentrations of natural radionuclides ²³⁸U, ²³²Th, and ⁴⁰K were comparable to those reported in other studies carried out in different countries. As well as their content in rivers and sediments was lower than those reported in neighboring region. Potassium-40 in food and ²¹⁰Po in fish were the main contributors to the internal dose. The average annual effective dose due to external exposure and internal, excluding radon gas which constitutes around 43 % of the total dose, was found to be lower than the total worldwide value, 2.4 mSv year⁻¹. Iodine-131 was detected in grass samples, collected in 2011 during Fukushima accident; its content ranged from 0.40 ± 0.06 to 0.9 ± 0.1 Bq kg⁻¹, as well as ¹³⁷Cs was detected in some seafood samples imported from Japan and neighboring countries. Its activity concentration varied between 0.15 ± 0.04 and 0.40 ± 0.02 Bq kg⁻¹.
Mostrar más [+] Menos [-]Genotoxicity in adult residents in mineral coal region—a cross-sectional study Texto completo
2017
Da Silva Pinto, Edlaine Acosta | Garcia, Edariane Menestrino | de Almeida, Krissia Aparecida | Fernandes, Caroline Feijó Lopes | Tavella, Ronan Adler | Soares, Maria Cristina Flores | Baisch, Paulo Roberto Martins | Muccillo-Baisch, Ana Luíza | da Silva Júnior, Flavio Manoel Rodrigues
The present study assessed the DNA damage in environmentally exposed volunteers living in seven municipalities in an industrial coal region, through the use of the comet assay with blood cells and the micronucleus test with buccal cells. Blood and buccal smears were collected from 320 male volunteers living in seven cities inserted in a coal region. They were ages of 18 and 50 years and also completed a questionnaire intended to identify factors associated with DNA damage through a Poisson regression analysis. The comet assay detected significant differences in DNA damage in volunteers from different municipalities, and neighboring cities (Pedras Altas, Aceguá, and Hulha Negra) had a higher level of DNA damage in relation to control city. Some of the risk factors associated with identified DNA lesions included residence time and life habits. On the other hand, the micronucleus test did not identify differences between the cities studied, but the regression analysis identified risk factors such as age and life habits (consumption of mate tea and low carbohydrates diet). We conclude that there are differences in the DNA damage of volunteers from different cities of the carboniferous region, but the presence of micronuclei in the oral mucosa does not differ between the same cities. Furthermore, we alert that some related factors may increase the risk of genotoxicity, such as residence location and time, and living and food habits. Finally, we suggest the need for continuous biomonitoring of the population, as well as for investing in health promotion in these vulnerable populations.
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