Groundwater quality assessment in the urban-west region of Zanzibar Island

This paper highlights the levels of anions (nitrate, nitrite, sulfate, bromide, chloride, and fluoride) and cations (potassium, sodium, magnesium, and calcium) in selected springs and groundwater sources in the urban-west region of Zanzibar Island. The levels of total dissolved solids (TDS) and sodium adsorption ratio (SAR) were also studied. Thirty water samples were collected in December 2012 from various types of water sources, which included closed hand-dug wells (CHDW), open hand-dug wells (OHDW), springwater (SW), public bore wells (PBW), and bore wells owned by private individuals (BWP), and analyzed after filtration and sometimes dilution. The cations were analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES). The anions were analyzed by chemically suppressed ion chromatography (IC). The ranges of the levels of the investigated parameters were as follows: Na 13.68–3,656 mg L^?1, K 2.66–583 mg L^?1, Mg 0.63–131.10 mg L^?1, Ca 16.79–189.9 mg L^?1, Cl^? 8.61–4,340.97 mg L^?1, F^? 0–1.02 mg L^?1, Br^? 0–10.88 mg L^?1, NO₃ ^? 0.18–342.4 mg L^?1, NO₂ ^? 0–1.39, SO₄ ^2? 4.43–534.02 mg L^?1, TDS 7–6,380 mg L^?1, and SAR 0.63–50. Except fluoride, most of the studied parameters in the water samples had concentrations beyond the permissible limits of the World Health Organization (WHO). The elevated concentrations are a result of seepage of contaminated water from on-site septic tanks, pit latrines, landfill leachates, fertilizer applications, and domestic effluents. These results should alert domestic water stakeholders in Zanzibar to the urgent task of initiating a quick mitigation response to control these alarming water risks.     

Interspecific and locational differences in metal levels in edible fish tissue from Saudi Arabia

Metal levels in fish have been extensively studied, but little data currently exists for the Middle East. We examined the levels of metals and metalloids (aluminum, arsenic, copper, manganese, selenium, zinc, and mercury) in the flesh of 13 fish species collected from three fishing sites and a local fish market in Jeddah, Saudi Arabia. We tested the following null hypotheses: (1) there are no interspecific differences in metal levels, (2) there are no differences in metal levels in fishes between market and fishing sites, (3) there are no size-related differences in metal levels, and (4) there are no differences in selenium:mercury molar ratio among different fish species. There were significant interspecific differences in concentrations for all metals. There was an order of magnitude difference in the levels of aluminum, arsenic, mercury, manganese, and selenium, indicating wide variation in potential effects on the fish themselves and on their predators. Fishes from Area II, close to a large commercial port, had the highest levels of arsenic, mercury, and selenium, followed by market fishes. Mercury was positively correlated with body size in 6 of the 13 fish species examined. Mercury was correlated positively with arsenic and selenium, but negatively with aluminum, cobalt, copper, manganese, and zinc. Selenium:mercury molar ratios varied significantly among species, with Carangoides bajad, Cephalopholis argus, Variola louti, and Ephinephelus tauvina having ratios below 10:1. These findings can be used in risk assessments, design of mercury reduction plans, development of fish advisories to protect public health, and future management decision-making.     

Mutagenicity and genotoxicity assessment of industrial wastewaters

The genotoxicity of industrial wastewaters from Jajmau (Kanpur), was carried out by Ames Salmonella/microsome test, DNA repair-defective mutants, and Allium cepa anaphase–telophase test. Test samples showed maximum response with TA98 strain with and without metabolic activation. Amberlite resins concentrated wastewater samples were found to be more mutagenic as compared to those of liquid–liquid extracts (hexane and dichloromethane extracts). The damage in the DNA repair defective mutants in the presence of Amberlite resins concentrated water samples were found to be higher to that of liquid–liquid-extracted water samples at the dose level of 20 μl/ml culture. Among all the mutants, polA exhibited maximum decline with test samples. Mitotic index (MI) of root tip meristematic cells of A. cepa treated with 5, 10, 25, 50, and 100 % (v/v) wastewaters were significantly lower than the control. Complementary to the lower levels of MI, the wastewaters showed higher chromosomal aberration levels in all cases investigated.     

Recommendations on chemicals management policy and legislation in the framework of the Egyptian–German twinning project on hazardous substances and waste management

The sustainable management of chemicals and their associated wastes—especially legacy stockpiles—is always challenging. Developing countries face particular difficulties as they often have insufficient treatment and disposal capacity, have limited resources and many lack an appropriate and effective regulatory framework. This paper describes the objectives and the approach of the Egyptian–German Twinning Project under the European Neighbourhood Policy to improve the strategy of managing hazardous substances in the Egyptian Environmental Affairs Agency (EEAA) between November 2008 and May 2011. It also provides an introduction to the Republic of Egypt’s legal and administrative system regarding chemical controls. Subsequently, options for a new chemical management strategy consistent with the recommendations of the United Nations Chemicals Conventions are proposed. The Egyptian legal and administrative system is discussed in relation to the United Nations’ recommendations and current European Union legislation for the sound management of chemicals. We also discuss a strategy for the EEAA to use the existing Egyptian legal system to implement the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals, the Stockholm Convention and other proposed regulatory frameworks. The analysis, the results, and the recommendations presented may be useful for other developing countries in a comparable position to Egypt aspiring to update their legislation and administration to the international standards of sound management of chemicals.     

Biosorption and biodegradation of Acid Orange 7 by Enterococcus faecalis strain ZL: optimization by response surface methodological approach

Reactive dyes account for one of the major sources of dye wastes in textile effluent. In this study, decolorization of the monoazo dye, Acid Orange 7 (AO7) by the Enterococcus faecalis strain ZL that isolated from a palm oil mill effluent treatment plant has been investigated. Decolorization efficiency of azo dye is greatly affected by the types of nutrients and the size of inoculum used. In this work, one-factor-at-a-time (method and response surface methodology (RSM) was applied to optimize these operational factors and also to study the combined interaction between them. Analysis of AO7 decolorization was done using Fourier transform infrared (FTIR) spectroscopy, desorption study, UV–Vis spectral analysis, field emission scanning electron microscopy (FESEM), and high performance liquid chromatography (HPLC). The optimum condition via RSM for the color removal of AO7 was found to be as follows: yeast extract, 0.1 %?w/v, glycerol concentration of 0.1 %?v/v, and inoculum density of 2.5 %?v/v at initial dye concentration of 100 mg/L at 37 °C. Decolorization efficiency of 98 % was achieved in only 5 h. The kinetic of AO7 decolorization was found to be first order with respect to dye concentration with a k value of 0.87/h. FTIR, desorption study, UV–Vis spectral analysis, FESEM, and HPLC findings indicated that the decolorization of AO7 was mainly due to the biosorption as well as biodegradation of the bacterial cells. In addition, HPLC analyses also showed the formation of sulfanilic acid as a possible degradation product of AO7 under facultative anaerobic condition. This study explored the ability of E. faecalis strain ZL in decolorizing AO7 by biosorption as well as biodegradation process.     

Study of Thermal Decomposition Kinetics of Palm Oleic Acid-Based Alkyds and Effect of Oil Length on Thermal Stability

Thermal decomposition kinetics of three palm oleic acid-based alkyds with different oil lengths and having different molecular weights were studied using TGA measurements under non-isothermal conditions. Activation energies were obtained from Kissinger and Ozawa, Flynn and Wall (OFW) methods and subsequently the pre-exponential factor, A, degradation rate constant, k, for all the alkyds were also determined. From kinetic analysis of the thermal decomposition using the OFW method, it was found that degradation of all the alkyds has taken place in more than two stages, corresponding to different mechanisms. As shown from Ozawa and Kissinger methods, the chemical composition of the alkyds influenced the thermal degradation; increasing the phthalic anhydride and glycerol, and decreasing the oleic acid increased the thermal stabilities of the alkyds.     

Biosynthesis and Characterization of Poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) from Bacillus cereus S10

The biodegradable and biocompatible copolymer poly-(3-hydroxybutyrate-co-5 mol% 3-hydroxyvalerate), poly-(3HB-co-5 mol% 3HV), was synthesized by Bacillus cereus S10 and the highest yield was determined as 69.91 % at pH 7 and 30 °C after 48 h of incubation using a glucose as the sole carbon source. Poly-(3HB-co-5 mol% 3HV) was purified from bacterial biomass using chloroform. FTIR analysis showed absorption bands at 1,723, 1,274, 1,373, 1,453, 2,932 cm^?1 corresponding to C=O, C–O stretching, CH₃, –CH₂ and –CH groups, respectively. ¹H-NMR and ¹³C-NMR analysis confirmed that the copolymer was composed of 95 mol% of 3-hydroxybutrate and 5 mol% of 3-HV monomeric units. Poly-(3-HB-co-5 mol% 3HV) was used for nanoparticles preparation. The diameter of nanoparticles was 202 nm.     

Trichoderma harzianum: a green sorbent for Pb(II) uptake from aqueous solutions

This investigation describes the use of specially cultivated, nonliving biomass of Trichoderma harzianum as a biosorbent for the batch removal of Pb(II) from a stirred system under different experimental conditions. The metal removal depended upon pH, sorbent particle size, initial Pb(II) concentration, shaking speed, and sorption time. The optimal experimental conditions for the removal of Pb(II) by T. harzianum with an initial metal concentration of 100 mg L^?1 were obtained at a particle size of 53 μm, a pH of 4.5, a shaking speed of 200 rpm, and a contact time of 720 min. The results were analyzed in terms of adsorption isotherms and kinetic models. The Freundlich isotherm model and pseudo second-order model fitted well in the data. T. harzianum proved to be a good biomaterial for accumulating Pb(II) from aqueous solutions (q = 460 mg g^?1).     

Visible-light-driven photocatalytic dual-layer hollow fibre membrane ameliorates the changes of bisphenol A exposure in gastrointestinal tract

Environmental Science and Pollution Research - Various treatments of choice are available to overcome contamination of bisphenol A (BPA) in the environment including membrane technologies; however,...     

Exploring chemical analysis of vermicompost of various oil palm fibre wastes

The aim of this work was to study the physical and chemical properties of different oil palm wastes, viz. empty fruit bunch (EFB), oil palm frond (OPF) and oil palm trunk (OPT). A study (84 days duration) was conducted to evaluate the efficiency of an exotic earthworm species (epigeic-African Nightcrawler (Eudrilus euginae)) for the decomposition of different types of oil palm wastes (EFB, OPT and OPF) into valuable vermicompost. The decrease in earthworm’s biomass gain for EFB, OPT and OPF may be due to exhaustion of worm feed in vermicomposters. The percentage of nitrogen, phosphorous and potassium in vermicompost was found to increase while pH and total organic carbon declined as a function of the vermicomposting period. The vermicompost obtained showed an increase in heavy metal content for all the reactors, but levels were still in the range of nutrient in the vermicompost. The data reveal that vermicomposting (using African Nightcrawler) is a suitable technology for the decomposition of oil palm wastes, especially EFB into value-added material.