Detecting micronuclei frequency in some aquatic organisms for monitoring pollution of Izmir Bay (Western Turkey)

Micronuclei tests is a system of mutagenicity testing used for determining the pollution and chemicals causing changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells. Damage caused on the DNA by genotoxic pollutants is the first consequence occurring in the aquatic organisms. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish Gobius niger and haemolymph and gills of mussels Mytilus galloprovincialis living in Izmir Bay at the level of DNA by the means of micronuclei (MN) test. Organisms used in the MN test were collected from seven locations (Alsancak, Alaybey Shipyard, Karsiyaka, Bostanli, Göztepe, Konak and Pasaport) which are known as the most polluted part of inner Bay of Izmir (Western Coast of Turkey). According to the results of the present study, frequency of MN was found at high level in Alaybey Shipyard and Pasaport where wastes from existing dockyard contributed to high level of pollution. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regular monitoring of pollution of coastal ecosystem.     

Separation and determination of trace levels of aromatic amines by HPLC

Aromatic amines were analysed by normal phase and reverse phase high performance liquid chromatography employing silica gel and octadecyl silane (ODS) columns, respectively. A number of mobile phases were used. The results obtained on silica gel column were compared with those achieved on reverse phase column. Excellent results were obtained on ODS and shoulder peaks were eliminated when a mixture of methyl alcohol and sodium perchlorate was used as mobile phase.     

The feasibility of decontamination of reduced saline sediments from copper using the electrokinetic process

The remediation of metal contamination in estuarine and reduced sediments is another challenge for the electrokinetic process. Problems result from the complex chemical composition of saline reduced sediments. In the experiments described here copper was added into saline reduced sediments to simulate the natural situation. Two constant voltages were applied across the electrokinetic cell to investigate the effect of an increase in potential difference on the electrokinetic process. Acetic acid at pH 6 and 4 was also added to the cathode in separate experiments to enhance copper removal. The results from this study showed that in the unenhanced experiments most of copper remained in the soil and was unaffected by the electrokinetic process. At the end of unenhanced electrokinetic experiments, the copper concentration was found only to be slightly changed in the anode region. Up to 21% of the copper was found precipitated near the anode when the applied voltage was 10V and this increased to 25% when the applied voltage was 7V. In the enhanced electrokinetic experiments up to 98% of copper was removed from section 1 and precipitated again in sections 2 and 3. This indicates that a significant amount copper removal from the saline sediments may be achieved by the enhanced electrokinetic process.     

A detailed kinetic investigation on the effects of hydrogen enrichment on the performance of gas-fueled SI engine

This study investigates the effects of hydrogen enrichment on formation of pollutants and greenhouse gases in gas-fueled spark ignition engines. To this end, a previously validated detailed mechanism is embedded with a comprehensive one-dimensional engine model and the results are verified with experimental observations at different compression ratios and engine loads. The simulations are then performed for different mixtures of hydrogen and natural gas. The results indicate that adding hydrogen increases the cylinder peak pressure at different loads and compression ratios, despite the fact that reduces the amount of carbon monoxide, carbon dioxide, and methane in all the conditions.     

Role of non-timber forest products in sustaining forest-based livelihoods and rural households' resilience capacity in and around protected area: a Bangladesh study†

People in the developing world derive a significant part of their livelihoods from various forest products, particularly non-timber forest products (NTFPs). This article attempts to explore the contribution of NTFPs in sustaining forest-based rural livelihood in and around a protected area (PA) of Bangladesh, and their potential role in enhancing households' resilience capacity. Based on empirical investigation, our study revealed that local communities gather a substantial amount of NTFPs from national park despite the official restrictions. Twenty seven percent households (HHs) of the area received at least some cash benefit from the collection, processing and selling of NTFPs, and NTFPs contribute to HHs' primary, supplementary and emergency sources of income. NTFPs also constituted an estimated 19% of HHs' net annual income, and were the primary occupation for about 18% of the HHs. HHs' dependency on nearby forests for various NTFPs varied vis-à-vis their socio-economic condition, as well as with their location from the park. Based on our case study, the article also offers some clues for improving the situation in PA.     

Unraveling prevalence and public health risks of arsenic,uranium and co-occurring trace metals in groundwater along riverine ecosystem in Sindh and Punjab,Pakistan

Environmental Geochemistry and Health - The current study focuses on the understanding of contamination status, distribution, source apportionment and health perspectives of arsenic (As), uranium...     

Lung function decrement with arsenic exposure to drinking groundwater along River Indus: a comparative cross-sectional study

This study was designed to determine the association between chronic arsenic exposure through drinking groundwater and decrement in lung function, particularly among individuals who do not have signs of arsenic lesions, among an adult population. This was a comparative cross-sectional study conducted during the months of January to March 2009. One hundred participants ≥15 years of age in each group, i.e. exposed (≥100 μg/l) and unexposed (≤10 μg/l) to arsenic, determined by testing drinking water samples (using portable kits), were compared for effects on lung function using spirometry. A structured and validated questionnaire was administered. Examination for arsenic skin lesions was also done. There was a decline in the mean adjusted FEV1 of 154.3 ml (95% CI: −324.7, 16.0; p = 0.076), in mean adjusted FVC of 221.9 ml (95% CI: −419.5, −24.3; p = 0.028), and in FEV1/FVC ratio of 2.0 (95% CI: −25.3, 29.4; p = 0.884) among participants who were exposed to arsenic compared to those unexposed. A separate model comprising a total of 160 participants, 60 exposed to arsenic concentrations ≥250 μg/l and 100 unexposed at arsenic concentrations of ≤10 μg/l, showed a decrement in mean adjusted FEV1 of 226.4 ml (95% CI: −430.4, −22.4; p = 0.030), in mean adjusted FVC of 354.8 ml (95% CI: −583.6, −126.0; p = 0.003), and in FEV1/FVC ratio of 9.9 (95% CI: −21.8, 41.6; p = 0.539) among participants who were exposed to arsenic in drinking groundwater. This study demonstrated that decrement in lung function is associated with chronic exposure to arsenic in drinking groundwater, occurring independently, and even before any manifestation, of arsenic skin lesions or respiratory symptoms. The study also demonstrated a dose-response effect of arsenic exposure and lung function decrement.     

Effect of vehicle exhaust on the quantity of polycyclic aromatic hydrocarbons (PAHs) in soil

PAHs are formed during the incomplete combustion of organic substances containing carbon and hydrogen and are one of the first atmospheric pollutants identified as carcinogens. Most of the PAH environmental burden is found in the soil (95%). Soil samples collected from different roadsides were analyzed for seven polycyclic aromatic hydrocarbons (PAHs). The quantitative and qualitative analysis was carried out by UV Spectrophotometer. The individual PAH value ranged from 0.1 to 18.0 mg/kg. Phenenthrene and Pyrene were found to be the most abundant compounds. Vehicle emissions are the principal source of PAH in the Roadside soils. The highest concentration was found at site S2 (Hasthtnagri Roadside) which shows the highest traffic density.     

Reuse of municipal effluent with drip irrigation and evaluation the effect on soil properties in a semi-arid area

Irrigation with municipal effluent was evaluated during 25 months in Southern Iran from 2003 to 2005 in which 14 tree species were irrigated with effluent and borehole water at an annual supply rate of 3,940 and 5,395 m(3) ha(-1), respectively. To mitigate the environmental effects, a drip irrigation system was designed and the amount of applied water based on pan evaporation was measured by flow meters and soil properties were monitored. The statistical results showed that the applied effluent had no adverse effect on soil properties. The soil salinity was reduced from 8.2, 6.8 and 7.0 dSm(-1) to 1.07, 1.12 and 3.5 dSm(-1 )in the soil layers 0-30, 30-60 and 60-90 cm, respectively. The SAR decreased significantly, while soil pH increased by 0.8 and 0.6 units in the layers 0-30 and 30-60 cm. A total application of 9,335 m(3)ha(-1 )of effluent with a nitrogen and phosphorus concentration of 7.9 and 10.3 mg l(-1), added 73 and 101 kg ha(-1) of nitrogen and phosphorus to the soil. Organic carbon also increased significantly. Twenty-five months irrigation with effluent caused a slight increase in soil bulk density and a slight decrease in mean permeability. Because of an efficient filtration and high discharge rate of bubblers (drippers), no considerable sign of clogging was observed.     

Markovian–Octant analysis based stable turbulent shear stresses in near-bed bursting phenomena of vortex settling chamber

The coherent structure in near-bed turbulent boundary layer of vortex chamber, particularly the bursting events and their associated shear stresses play the main role in sediment flushing process and consequently the trap efficiency of the vortex settling chamber. Hence, three-dimensional velocity measurements were made at 48 points near the bed of physical model of vortex chamber by using Micro-ADV. The pattern of sediment deposition at the bed of vortex settling chamber reveals three separate regions formed by three predominant currents of inlet flow, flushing flow and outlet over flow. Additionally, due to the instability and three-dimensional nature of the bursting events near the bed of chamber, the new method of Markovian–Octant analysis was applied to study the different classes of near-bed stable shear stresses of vortex chamber in three dimensions. Moreover, the role of each class of stable shear stresses on Sediment transport mechanism at the bed of vortex chamber is investigated.