An HPLC method development for the assessment of degradation products of anthraquinone dye

The behavior of metsulfuron-methyl and its residues in an artificial pond was studied using a ¹⁴C isotopic tracer technique. Throughout the experimental period, the majority of metsulfuron-methyl residues were sustained in the pond water. Furthermore, the metsulfuron-methyl residues were just found in the surface layer of the sediment, and the transfer distance of these residues had only reached 9?C12 cm by the end of the experiment. The extract residues of metsulfuron-methyl in sediment were slightly higher than those of the bound residues (BR) during the initial experiment stage, while the BR dominated the surface sediment after 45 days. Finally, the metsulfuron-methyl residues could be combined with humus in the surface sediment, and the distribution of metsulfuron-methyl residues in fulvic acid was significantly higher than that in humic acid.     

A Study on the Combined Effect of Noise and Vibration on Operators’ Performance of a Readability Task in a Mobile Driving Environment

This paper presents a study in which the main objective was to investigate the combined effect of noise and vibration on the performance of a readability task in a mobile driving environment. Subjects performed a readability task on a laptop computer in a sitting posture with their backs supported with a backrest under varying levels of noise and vibration. The data in terms of the mean number of characters read per minute were collected and statistically analyzed. Results showed that the individual effect of noise, vibration, and the operators’ gender as well as the interaction between gender and noise, and gender and vibration were statistically significant. However, the combined effect of noise and vibration was not found to be statistically significant. Results also indicated that gender was statistically significant at all levels of noise as well as vibration, and noise and vibration were statistically significant at both levels of gender.     

An ecosystem approach to analyse the livelihood of fishers of the Old Brahmaputra River in Mymensingh region,Bangladesh

This paper applies an ecosystem approach to analyse the livelihood of fishers dependent on the Old Brahmaputra River in Mymensingh, Bangladesh. Results suggest that the livelihood of fishers is increasingly threatened because of the fragile river ecosystem and poor livelihood assets. Most fishers face a wide range of vulnerability including shocks, trends and seasonality. This is because the ecosystem of the resource base on which their livelihood depends (i.e. the Old Brahmaputra River) has been degraded severely resulting in a significant decline in fish catch due to a combination of factors, such as over-fishing, use of destructive fishing gears, water pollution, siltation, rapid urbanisation and environmental degradation. We propose an adoption of the socio-ecological system with active community participation in the management of the resource base and collaboration amongst key stakeholders to produce positive livelihood outcomes for the fishers.     

Distribution of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, dioxin-like polychlorinated biphenyl and polycyclic aromatic hydrocarbons in the sediment of Temsah lake, Suez Canal, Egypt

Lake Temsah is one of the main wetlands in the Suez Canal region, and the main source for fish for the area. The lake is the end-point of several wastewater effluents. In the present study, residues of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyl (PCB) and polycyclic aromatic hydrocarbons (PAH) were monitored in the sediment of the lake. Samples were collected from six different sampling stations around the lake using a box-corer sampler, then kept frozen. Samples were extracted and cleaned up before residue determination was conducted using an HRGC/HRMS. An HP 6890 plus gas chromatograph was coupled to a Micromass Autospec Ultima mass spectrometer operating in EI mode at 35 eV and with a resolution of 10.000 (5% valley). PCDDs and PCDFs were detected in all sediment samples collected from various sampling stations. Results showed some progressive increase in PCDDs concentrations relevant to increase in chlorination. In the PCDD group of congeners, 1, 2, 3, 4, 6, 7, 8, 9 octa-CDD had the highest detected concentrations in all samples, while 2, 3, 7, 8 tetra-CDD showed the lowest concentrations. The World Health Organization toxicity equivalents ranged from 0.387 to 11.20 ng kg^-1 d.w. For PCDD homologues, hexa-CDD was the most dominant homologue in all sediment samples analysed. Regarding dioxin-like PCBs, results showed that IUPAC No. 118 congener, 2, 3, 4, 4, 5, pentachlorobiphenyl was the most concentrated of all detected congeners, with concentrations ranging between 0.039 and 43.201 µg kg^-1. For polycyclic aromatic hydrocarbons, benzo(b+k+j)fluoranthene had the highest concentrations in almost all sampling stations. However, fluorene was the smallest detected concentration in almost all stations. This result would indicate that PAH contamination of the lake seems to be coming from one main source in all sampling stations. The present work is the first record of PCCDs, PCCFs, and dioxin-like PCBs in the Temsah lake. The concentrations of the contaminants monitored in this study, especially those of PAHs, are rather alarming. Efforts should be made to stop point sources that contaminate the lake.     

Population structure of four species of porcellanid crabs (Decapoda: Anomura) occurring on the coast of Karachi

The population structure of 4 species of porcellanid crabs, including 2 species of Petrolisthes (P. boscii and P. rufescens) and 2 of Pachycheles (P. tomentosus and P. natalensis) was investigated. Sex ratios deviated from the expected 1:1 distribution in some size classes of the 4 species, but conformed in general to this pattern on the entire population basis. Probability curves developed from sex ratios differ markedly in shape and slope and resemble Wenner's (1972) anomalous and intermediate types. Ovigerous females of Petrolisthes boscii occurred for 9 months, of P. rufescens for 11 months; those of Pachycheles tomentosus and P. natalensis occurred throughout the year. In every size class, a considerably higher number of female Pachycheles tomentosus and P. natalensis became ovigerous than in Petrolisthes boscii and P. rufescens. Size-frequency distributions of the 4 species were unimodal, indicating that recruitment to crab populations was gradual. Juveniles of Petrolisthes boscii and P. rufescens were most abundant towards the commencement of the southwest monsoon season, in June–July; juveniles of Pachycheles tomentosus and P. natalensis were most abundant during the premonsoon month of March. Thirteen percent of Pachycheles natalensis were infected by a bopyrid parasite; the bopyrid also infected 5.2% of Petrolisthes rufescens and 0.6% of P. boscii. The latter two species were also infected by a rhizocephalan parasite, the infection rates being inverse to those by the bopyrid, i.e., 0.3 and 6.4%, respectively.     

Oil pollution studies in the Nile River. I. Survey of oil and grease in Nile water

A survey of oil and grease along the Nile River indicated the presence of variable concentrations of these pollutants. It was found that some stations along the Nile are more polluted than others. These are located mostly at lake Nasser port (Aswan segment); oil distribution centers and ship waiting areas (Assiut segment); boat docks, a ship yard, and an electric power station (Cairo segment); and at factory areas (Rossetta segment). The level of oil and grease decreased significantly when moving downstream. In addition, the level of oil and grease along the river was lower in summer than in winter and spring. This may be attributed to the decrease of activities and increase of vaporization processes.     

Correction to: Hydrogen production,storage, utilisation and environmental impacts: a review

Environmental Chemistry Letters -     

Integration of biogas systems into a carbon zero and hydrogen economy: a review

Environmental Chemistry Letters - The Ukraine conflict has put critical pressure on gas supplies and increased the price of fertilisers. As a consequence, biogas has gained remarkable attention as...     

Exploring the multifaceted role of TGF-β signaling in diabetic complications

Environmental Science and Pollution Research - Diabetes is one of the most comprehensive metabolic disorders and is spread across the globe. The data from IDF Diabetes Atlas and National Diabetes...