Coffee,its roasted form,and their residues cause birth failure and shorten lifespan in dengue vectors

Environmental Science and Pollution Research - In dengue mosquitoes, successful embryonic development and long lifespan are key determinants for the persistence of both virus and vector. Therefore,...     

Monsoonal differences and probability distribution of PM10 concentration

There are many factors that influence PM₁₀ concentration in the atmosphere. This paper will look at the PM₁₀ concentration in relation with the wet season (north east monsoon) and dry season (south west monsoon) in Seberang Perai, Malaysia from the year 2000 to 2004. It is expected that PM₁₀ will reach the peak during south west monsoon as the weather during this season becomes dry and this study has proved that the highest PM₁₀ concentrations in 2000 to 2004 were recorded in this monsoon. Two probability distributions using Weibull and lognormal were used to model the PM₁₀ concentration. The best model used for prediction was selected based on performance indicators. Lognormal distribution represents the data better than Weibull distribution model for 2000, 2001, and 2002. However, for 2003 and 2004, Weibull distribution represents better than the lognormal distribution. The proposed distributions were successfully used for estimation of exceedences and predicting the return periods of the sequence year.     

Combustion in porous media and its applications – A comprehensive survey

The rapid advances in technology and improved living standard of the society necessitate abundant use of fossil fuels which poses two major challenges to any nation. One is fast depletion of fossil fuel resources; the other is environmental pollution. The porous medium combustion (PMC) has proved to be one of the technically and economically feasible options to tackle the aforesaid problems to a remarkable extent. PMC has interesting advantages compared with free flame combustion due to the higher burning rates, the increased power dynamic range, the extension of the lean flammability limits, and the low emissions of pollutants. This article provides a comprehensive picture of the global scenario of research and developments in PMC and its applications that enable a researcher to decide the direction of further investigation. The works published so far in this area are reviewed, classified according to their objectives and presented in an organized manner with general conclusions. A separate section is devoted for the numerical modeling of PMC.     

Cellulose and Nanocellulose from Maize Straw: An Insight on the Crystal Properties

In this work cellulose was extracted from corn/maize straw (Zea mays) by means of an environmental-friendly multistep procedure involving alkaline treatment and a totally chlorine-free bleaching. This multistep procedure efficiently removed lignin and hemicelluloses. The pulp resulting from each step was characterized by attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR). The optimum pulping time (time of alkaline treatment) was determined by means of thermogravimetric analysis. The extracted cellulose is highly crystalline as verified by X-ray diffraction. The partial acid hydrolysis with sulfuric acid led to the isolation of cellulose whiskers in aqueous suspension as confirmed by light scattering and transmission electron microscopy. The depolarization ratio value of these nanocrystals is the same as that determined for cotton whiskers, showing that this ratio does not depend on the cellulose source. The maize whiskers are arranged laterally in bundles with average thickness around five times that of the crystallite.     

Enhancing Performance of Sphingobacterium spiritivorum in Bioremediation Phenanthrene Contaminated Sand

Many biodegradation studies have focused on survival of isolated bacteria to increase the bacteria population and subsequently enhance the efficiency of polycyclic aromatic hydrocarbon (PAH) biodegradation. However, there is limited research on enhancing the performance of isolated bacteria through reinoculation. Thus, this study was designed to evaluate the effects of reinoculation on the performance of Sphingobacterium spiritivorum in degradation of phenanthrene contaminated sand. Experiments were performed in three different reactors. Inoculation was performed once (day 0) in reactor 1. In reactor 2, inoculation was performed twice (day 0 and day 5). The bacteria was isolated from reactor 2 and inoculated into reactor 3. The study results show reactor 3 having the highest degradation rate (13.61 mg/kg/day) and percentage removal (95.36 percent). In contrast, without reinoculation in reactor 1, 68.93 percent of phenanthrene was removed. Thus, the performance of S. spiritivorum in phenanthrene degradation can be enhanced through reinoculation. © 2014 Wiley Periodicals, Inc.     

Pesticide risk assessment: A study on inhalation and dermal exposure to 2,4-D and paraquat among Malaysian paddy farmers

A cross-section analytical study was conducted to evaluate the risk of pesticide exposure to those applying the Class II pesticides 2,4-D and paraquat in the paddy-growing areas of Kerian, Perak, Malaysia. It investigated the influence of weather on exposure as well as documented health problems commonly related to pesticide exposure. Potential inhalation and dermal exposure for 140 paddy farmers (handlers of pesticides) were assessed. Results showed that while temperature and humidity affected exposure, windspeed had the strongest impact on pesticide exposure via inhalation. However, the degree of exposure to both herbicides via inhalation was below the permissible exposure limits set by United States National Institute of Occupational Safety and Health (NIOSH). Dermal Exposure Assessment Method (DREAM) readings showed that dermal exposure with manual spraying ranged from moderate to high. With motorized sprayers, however, the level of dermal exposure ranged from low to moderate. Dermal exposure was significantly negatively correlated with the usage of protective clothing. Various types of deleterious health effects were detected among users of manual knapsack sprayers. Long-term spraying activities were positively correlated with increasing levels of the gamma-glutamyl transpeptidase (GGT) liver enzyme. The type of spraying equipment, usage of proper protective clothing and adherence to correct spraying practices were found to be the most important factors influencing the degree of pesticide exposure among those applying pesticides.     

Techno-economic assessment of municipal solid waste management in Jordan

Mismanagement of solid waste leads to public health risks, adverse environmental impacts and other socio-economic problems. This is obvious in many developing countries around the world. Currently, several countries have realized that the way they manage their solid wastes does not satisfy the objectives of sustainable development. Therefore, these countries, including Jordan, which forms the case study presented here, have decided to move away from traditional solid waste management (SWM) options to more integrated solid waste management approaches. Unfortunately, in many developing countries like Jordan, the lack of adequate resources to implement the necessary changes is posing a serious obstacle. The present paper discusses the various practices and challenges of solid waste management in Jordan from both a technical and economic perspective. An overview of the current practices and their environmental implications in three major cities of the country, which generate more than 70% of the country's solid waste, is presented. Recent literature on solid waste management in Jordan has been reviewed; and data on the total amount of municipal solid waste generated, compositional variations over the last two decades, and future projections are presented. The necessity, importance and needs of solid waste recovery and reuse are identified. The review of the legal frameworks indicated that there is a need for detailed and clear regulations dealing specifically with solid waste. The service cost analysis revealed that none of the municipalities in Jordan sufficiently recover the cost of the services, with more than 50% being subsidized from the municipalities' budgets. The allocation of the available resources was analyzed and service performance indicators assessed. Factors that should be taken into consideration when making the decision to move from a traditional SWM approach to a more integrated approach are highlighted and suggestions for a more smooth transition are recommended.     

Poly(Acrylic Acid) Grafted Sodium Alginate Di-Block Hydrogels as Efficient Biosorbents; Structure-Property Relevance

Naturally-based poly(acrylic acid) grafted sodium alginate di-block hydrogels were investigated as high efficiency biosorbents for copper(II) ion. The grafted di-block hydrogel was characterized using FTIR, TGA and SEM techniques. Blank and immobilized algal biosorbent beads formed via 2.0% (w/w) calcium ions were also investigated. Batch adsorption experiments revealed optimal pH dependence of copper(II) ion biosorption at pH 5.5 with high efficient copper(II) ion uptake of 98.5 mg/g. The dynamics studies showed that the high efficiency copper(II) ion biosorption followed pseudo-second order kinetics with significant contribution of intraparticle diffusion mechanism. The equilibrium data fitted to Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) adsorption isotherm models. Thermodynamics parameters for copper(II) biosorption on blank and immobilized algal beads depicted the spontaneous nature of the biosorption process. Such high efficiency, feasibility, simplicity, and low cost properties adapt the di-block biosorbent to be the next generation promising biosorbents for water decontamination and to help in the recovery of the missing ecologic harmony.     

Analysis of per- and polyfluoroalkyl substances in Houston Ship Channel and Galveston Bay following a large-scale industrial fire using ion-mobility-spectrometry-mass spectrometry

Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants of concern because of their ubiquitous presence in surface and ground water; analytical methods that can be used for rapid comprehensive exposure assessment and fingerprinting of PFAS are needed. Following the fires at the Intercontinental Terminals Company (ITC) in Deer Park, TX in 2019, large quantities of PFAS-containing firefighting foams were deployed. The release of these substances into the Houston Ship Channel/Galveston Bay (HSC/GB) prompted concerns over the extent and level of PFAS contamination. A targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based study of temporal and spatial patterns of PFAS associated with this incident revealed presence of 7 species; their levels gradually decreased over a 6-month period. Because the targeted LC-MS/MS analysis was focused on about 30 PFAS molecules, it may have missed other PFAS compounds present in firefighting foams. Therefore, we utilized untargeted LC-ion mobility spectrometry-mass spectrometry (LC-IMS-MS)-based analytical approach for a more comprehensive characterization of PFAS in these water samples. We analyzed 31 samples from 9 sites in the HSC/GB that were collected over 5 months after the incident. Our data showed that additional 19 PFAS were detected in surface water of HSC/GB, most of them decreased gradually after the incident. PFAS features detected by LC-MS/MS correlated well in abundance with LC-IMS-MS data; however, LC-IMS-MS identified a number of additional PFAS, many known to be components of firefighting foams. These findings therefore illustrate that untargeted LC-IMS-MS improved our understanding of PFAS presence in complex environmental samples.