A review on bisphenol A occurrences,health effects and treatment process via membrane technology for drinking water

Massive utilization of bisphenol A (BPA) in the industrial production of polycarbonate plastics has led to the occurrence of this compound (at μg/L to ng/L level) in the water treatment plant. Nowadays, the presence of BPA in drinking water sources is a major concern among society because BPA is one of the endocrine disruption compounds (EDCs) that can cause hazard to human health even at extremely low concentration level. Parallel to these issues, membrane technology has emerged as the most feasible treatment process to eliminate this recalcitrant contaminant via physical separation mechanism. This paper reviews the occurrences and effects of BPA toward living organisms as well as the application of membrane technology for their removal in water treatment plant. The potential applications of using polymeric membranes for BPA removal are also discussed. Literature revealed that modifying membrane surface using blending approach is the simple yet effective method to improve membrane properties with respect to BPA removal without compromising water permeability. The regeneration process helps in maintaining the performances of membrane at desired level. The application of large-scale membrane process in treatment plant shows the feasibility of the technology for removing BPA and possible future prospect in water treatment process.     

A dynamic modelling approach for estimating critical loads of nitrogen based on plant community changes under a changing climate

A dynamic model of forest ecosystems was used to investigate the effects of climate change, atmospheric deposition and harvest intensity on 48 forest sites in Sweden (n = 16) and Switzerland (n = 32). The model was used to investigate the feasibility of deriving critical loads for nitrogen (N) deposition based on changes in plant community composition. The simulations show that climate and atmospheric deposition have comparably important effects on N mobilization in the soil, as climate triggers the release of organically bound nitrogen stored in the soil during the elevated deposition period. Climate has the most important effect on plant community composition, underlining the fact that this cannot be ignored in future simulations of vegetation dynamics. Harvest intensity has comparatively little effect on the plant community in the long term, while it may be detrimental in the short term following cutting. This study shows: that critical loads of N deposition can be estimated using the plant community as an indicator; that future climatic changes must be taken into account; and that the definition of the reference deposition is critical for the outcome of this estimate.     

Strength and durability characterization of pelletized coal–biomass household briquettes

Increase in waste sludge disposal is always seen as a problem from the point of production industry. However, it is clear that the reuse and recycle of sewage sludge could be a serious economic input. The most important action should be to determine the sludge characterizations and direct the producers towards appropriate reuse and recycling opportunities. In this study, reuse method was examined to produce coal briquette, which will constitute an example for waste sludge. In order to make use of the waste sludge, five different coal briquette samples were produced by mixing powdered coal and bitumen together with waste sludge, at different ratios. The overall results indicated that the sample named CB3 having 70% powdered coal, 20% waste sludge, and 10% bitumen was found to be the optimum coal briquette among the other samples produced. The proximate analysis of the optimum briquette sample was carried out according to the Turkish standards and regulations and it was found out that the produced briquette coal can have commercial value with a gross calorific value of 30.03 MJ/kg and 7.30% ash content.     

Ecology of sandy beaches in Oman

The benthic macrofauna and physical features of 10 sandy beaches along the coast of Oman were surveyed quantitatively. This is a mesotidal regime mostly subject to low to moderate wave energy but more exposed in the south. Five northern beaches are tide-dominated, with low wave energy, and their profiles consist of a berm, a steep, swash-dominated upper shore and a broad tide-dominated terrace from mid-shore downwards. They are composed of moderately sorted fine to medium sands. Southern beaches experience greater wave energy, particularly during the summer southwest monsoon, and exhibit smoother, concave profiles with fine, fairly well sorted carbonate sand. 58 species and species groups were recorded, with crustanceans, polychaetes and molluscs dominant. In general species richness was high, at least 19–25 species per beach, but dry biomass moderate to low at 26–90g/m shoreline, with one high value of 450g/m. Total abundance was moderate at 3–73×10³ organisms/m of beach. Some zonation was evident with ocypodid crabs andTylos in the supralittoral, cirolanid isopods on the upper shore and a variety of species on the lower shore. The coast of Oman appears to constitute a single zoogeographic region, but with some regional differentiation between north and south due to varying physical conditions. Thus, OmanÕs beaches are characterized by tide-dominated morphodynamics and exceptionally high species richness.     

Effectiveness in the use of natural gas for the reduction of atmospheric emissions: case study--industrial sector in the metropolitan region of Santiago,Chile

The purpose of this investigation was to quantify the potential of natural gas to reduce emissions from stationary combustion sources by analyzing the case study of the metropolitan region of Santiago, Chile. For such purposes, referential base scenarios have been defined that represent with and without natural gas settings. The method to be applied is an emission estimate based on emission factors. The results for this case study reveal that stationary combustion sources that replaced their fuel reduced particulate matter (PM) emissions by 61%, sulfur oxides (SOx) by 91%, nitrogen oxides (NOx) by 40%, and volatile organic compounds (VOC) by 10%. Carbon monoxide (CO) emissions were reduced by 1%. As a result of this emission reduction, in addition to reductions caused by other factors, such as a shift to cleaner fuels other than natural gas, technological improvements, and sources which are not operative, emission reduction goals set forth by the environmental authorities were broadly exceeded.     

Statistical modeling and response surface optimization on natural weathering of wood–plastic composites with calcium carbonate filler

Journal of Material Cycles and Waste Management - An experimental mixture design was used to determine the optimum composition of wood–plastic composites (WPCs), manufactured from recycled...     

Age at first marriage and its relation to fertility in Bangladesh

The 2007 Bangladesh Demographic and Health Survey(BDHS)data are exploited to examine the effects of socioeconomic and demographic factors on age at first marriage linkage to reproductive behavior of Bangladeshi women.The mean age at first marriage of women is found to be 15.48 years.Multivariate logistic regression technique shows that place of residence,religion,region,wealth index,education,and occupation are significantly important factors for determining age at first marriage.The relationship between marriage and fertility suggests that women who marry at a younger age produce more children than women who marry late.Findings of this study show that if the age at first marriage of adolescents is increased by 1 year,the age at first birth is postponed by 0.728 years.With the increase in age at first marriage,the fecundability of women sharply rises,whereas the proportion of temporary sterility decreases.Although there is a positive association between age at first marriage and age-specific marital fertility rates,the total parity per woman at the end of the reproductive period is expected to reduce by 0.196 for each 1-year delayed marriage.     

Income inequality,ecological footprint,and carbon dioxide emissions in Asian developing economies: what effects what and how?

The reduction of income inequality and environmental vulnerability is the most important factor, through which we can achieve the target of Sustainable Development Goals (SDGs). The past papers have investigated the nexus between income inequality and carbon emissions; however, the relationship between income inequality and carbon emissions along with ecological footprint has not been studied in the case of developing countries. To this end, this study analyzed the impact of income inequality on both carbon emissions and ecological footprint as well as the impact of carbon emission and ecological footprint on income inequality by using the dataset from 2006 to 2017 for the 18 Asian developing economies. This study confirmed the positive relationship between carbon emissions, ecological footprint, and income inequality under the methodology of Driscoll and Kraay (D&K) standard error approach. Specifically, a higher-income gap is destructive for environmental degradation, whereas increasing level of carbon emissions and ecological footprint also leads to rising income inequality in the investigated region. Furthermore, foreign direct investment (FDI), easy access to electricity, and population growth control income inequality, but they have a detrimental effect on both ecological footprint and carbon emissions. The empirical findings also provide some important policy implications.

     

Temporal variations in the level of chlordecone in seawater and marine organisms in Martinique Island (Lesser Antilles)

Environmental Science and Pollution Research - The present study, conducted in the Galion Bay in Martinique, aims to highlight the temporal and seasonal variations of chlordecone contamination (an...     

Residues of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides in organically-farmed vegetables

The residues of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in soils from organic farms and their uptake by four varieties of organic-produced potatoes and three varieties of organic carrots from England were investigated. Samples of the soils, crop peels and cores were all Soxhlet-extracted in triplicate, cleaned up by open-column chromatography and analysed by a multi-residue analytical method using gas chromatography with mass selective detection. The concentrations of PAHs, PCBs and OCPs in soils from organic farms ranged from 590+/-43 to 2301+/-146 microg/kg, 3.56+/-0.73 to 9.61+/-1.98 microg/kg and 52.2+/-4.9 to 478+/-111 microg/kg, respectively. Uptake by different crop varieties were 8.42+/-0.93 to 40.1+/-4.9 microg/kg sigmaPAHs, 0.83+/-0.19 to 2.68+/-0.94 microg/kg sigmaPCBs and 8.09+/-0.83 to 133+/-27 microg/kg sigmaOCPs. Residue uptake from soils depended on plant variety; Desiree potato and Nairobi carrot varieties were more susceptible to PAH contamination. Likewise, uptake of PCBs and OCPs depended on potato variety. There were significant positive correlations between the PCB and OCP concentrations (P<0.05) in soils and carrots but no significant correlation was found between the concentrations of any contaminants in soils and potatoes. Peeling carrots and potatoes was found to remove 52-100% of the contaminant residues depending on crop variety and the properties of the contaminants. Soil-crop bioconcentration factors (BCFs) decreased with increasing logK(ow) for PAHs up to about 4.5 and for PCBs up to about 6.5, above which no changes were discernible for either class of contaminants. No relationship was observed between soil-crop BCFs and logK(ow) for OCPs, most likely because their concentrations were low and variable.