Monitoring of PAHs and alkylated PAHs in aquatic organisms after 1 month from the Solar I oil spill off the coast of Guimaras Island, Philippines

Following the oil spill accident of the Solar I tanker in 2006 off the coast of Guimaras Island in the Philippines, polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in some aquatic organisms were investigated at Luzaran in Guimaras and Taklong Islands, which were heavily polluted with spilled oil, immediately and 1 month after the accident. The concentrations of total PAHs were 11.9–52.3 ng/g dry weight in fish. Meanwhile, total PAH concentrations in shellfish were 38.0–3,102 ng/g dry weight in Luzaran and 128–236 ng/g dry weight in Taklong. Pyrene, phenanthrene, and fluoranthene were dominant in most fish and chrysene in all shellfish. Significantly higher concentrations of all alkylated homologs were detected in shellfish than in fish. These differences had two possible causes, that is, the differences between fish and shellfish could be attributed to the uptake routes and/or their metabolizing abilities.     

Unexpected release of HNO<Subscript>3</Subscript> and related species from UV-illuminated TiO<Subscript>2</Subscript> surface into air in photocatalytic oxidation of NO<Subscript>2</Subscript>

We have discovered that HNO₃ and related species are released from the TiO₂ surface into air in the TiO₂ photocatalytic oxidation of NO₂ (1 ppm) under continuous UV light illumination (1 mW cm⁻²) by dehumidifying the outlet gas of the reaction and analyzing the recovered condensate liquid by ion chromatography. The origin of the HNO₃ recovered in the dehumidifier could not be explained by a simple desorption of HNO₃ overproduced on the TiO₂ surface. The produced HNO₃ must be activated on the TiO₂ surface and causing the unidentified reaction.     

Estimation and field measurement of methane emission from waste landfills in Hanoi, Vietnam

A methodology for estimating the methane emissions from waste landfills in Hanoi, Vietnam, as part of a case study on Asian cities, was derived based on a survey of documents and statistics related to waste management, interviews with persons in charge, and field investigations at landfill sites. The waste management system in Hanoi was analyzed to evaluate the methane emissions from waste landfill sites. The quantity of waste deposited into the landfill was evaluated from an investigation of the waste stream. The composition of municipal waste was surveyed in several districts in the Hanoi city area, and the quantities of degradable organic waste that had been deposited into landfill for the past 15 years were estimated. Field surveys on methane emissions from landfills of different ages (0.5, 2, and 8 years) were conducted and their methane emissions were estimated to be 120, 22.5, and 4.38 ml/min/m², respectively. The first-order reaction rate of methane generation was obtained as 0.51/year. Methane emissions from waste landfills were calculated by a first-order decay model using this emission factor and the amount of landfilled degradable waste. The estimates of methane emissions using the model accorded well with the estimates of the field survey. These results revealed that methane emissions from waste landfills estimated by regional-specific and precise information on the waste stream are essential for accurately determining the behavior of methane emissions from waste landfills in the past, present, and future.     

Decolorization and estrogenic activity of colored livestock wastewater after electrolysis treatment

Livestock wastewater is treated by activated sludge treatment. Untreated livestock wastewater has high estrogen activity because animal excreta contains estrogen. When activated sludge treatment is applied, the estrogen activity declines or is lost. However, the color of treated livestock wastewater is deep brownish-red because of the decomposition of organic compounds or the synthesis of metabolites. Discharging colored wastewater to the environment could cause some problems, so it is necessary to decolorize colored wastewater before it is discharged. It has been suggested that electrolysis decolorization technology is suitable for treating colored wastewater; however, the process produces volatile organic compounds (VOCs). In fact, little research has been conducted with reference to estrogen activity in wastewater that has undergone electrolysis, especially on the contribution of the electrolysis decolorization process to estrogen activity, i.e., the possibility of resynthesis of some substance with estrogen activity due to resolved and metabolized colored components. In this study, the concentration of VOC was measured for various electrolysis conditions, and estrogen activity was examined using a yeast two-hybrid assay. From the results, decolorization of colored livestock wastewater by electrolysis was possible, and the VOC generation during electrolysis could be controlled depending on the electrolysis conditions. Estrogen activity in colored livestock wastewater disappeared on electrolysis decolorization.     

Natural disaster mitigation through voluntary donations in a developing country: the case of Bangladesh

Environmental Economics and Policy Studies - This paper addresses voluntary donations in Bangladesh with a specific eye on natural disaster mitigation. We conducted a questionnaire survey of 1000...     

Histopathological alterations in gill,liver and kidney of common carp exposed to chlorpyrifos

Histopathological alterations in gill, liver and kidney of common carp, Cyprinus carpio, intoxicated with sub-lethal concentrations of chlorpyrifos (O,O,-diethyl-O-3,5,6-trichloro-2-pyridyl phosphorothioate) pesticide (1 and 100 μg/L) for a period of 14 days were analyzed under light microscope. Gill exhibited hyperplasia and hypertrophy of gill epithelium, blood congestion, dilation of marginal channel, epithelial lifting, lamellar fusion, lamellar disorganization, lamellar aneurysm, rupture of the lamellar epithelium, rupture of pillar cells and necrosis. Alterations in hepatocytes were more pronounced, including nuclear and cellular hypertrophy, cellular atrophy, irregular contour of cells and nucleus, cytoplasmic vacuolation, cytoplasmic and nuclear degeneration, cellular rupture, pyknotic nucleus, necrosis and melanomacrophages aggregations. Histopathological lesions in kidney were cellular and nuclear hypertrophy, narrowing of tubular lumen, cytoplasmic vacuolation, hyaline droplet degeneration, nuclear degeneration, occlusion of tubular lumen, tubular regeneration, dilation of glomerular capillaries, degeneration of glomerulus and hemorrhage in Bowman's space. The most significant conclusion drawn from this study was that with the increased concentration and duration the toxicosis of chlorpyrifos would be enhanced as shown through the analysis of mean assessment value (MAV) and degree of tissue changes (DTC) also.     

"Venom" of the slow loris: sequence similarity of prosimian skin gland protein and Fel d 1 cat allergen

Bites inflicted on humans by the slow loris (Nycticebus coucang), a prosimian from Indonesia, are painful and elicit anaphylaxis. Toxins from N. coucang are thought to originate in the brachial organ, a naked, gland-laden area of skin situated on the flexor surface of the arm that is licked during grooming. We isolated a major component of the brachial organ secretions from N. coucang, an approximately 18 kDa protein composed of two 70-90 amino-acid chains linked by one or more disulfide bonds. The N-termini of these peptide chains exhibit nearly 70% sequence similarity (37% identity, chain 1; 54% identity, chain 2) with the two chains of Fel d 1, the major allergen from the domestic cat (Felis catus). The extensive sequence similarity between the brachial organ component of N. coucang and the cat allergen suggests that they exhibit immunogenic cross-reactivity. This work clarifies the chemical nature of the brachial organ exudate and suggests a possible mode of action underlying the noxious effects of slow loris bites.     

Estimation of Vegetation Coverage in Semi-arid Sandy Land Based on Multivariate Statistical Modeling Using Remote Sensing Data

The estimation of vegetation coverage is essential in the monitoring and management of arid and semi-arid sandy lands. But how to estimate vegetation coverage and monitor the environmental change at global and regional scales still remains to be further studied. Here, combined with field vegetation survey, multispectral remote sensing data were used to estimate coverage based on theoretical statistical modeling. First, the remote sensing data were processed and several groups of spectral variables were selected/proposed and calculated, and then statistically correlated to measured vegetation coverage. Both the single- and multiple-variable-based models were established and further analyzed. Among all single-variable-based models, that is based on Normalized Difference Vegetation Index showed the highest R (0.900) and R ² (0.810) as well as lowest standard estimate error (0.128024). Since the multiple-variable-based model using multiple stepwise regression analysis behaved much better, it was determined as the optimal model for local coverage estimation. Finally, the estimation was conducted based on the optimal model and the result was cross-validated. The coefficient of determination used for validation was 0.867 with a root-mean-squared error (RMSE) of 0.101. The large-scale estimation of vegetation coverage using statistical modeling based on remote sensing data can be helpful for the monitoring and controlling of desertification in arid and semi-arid regions. It could serve for regional ecological management which is of great significance.     

Development of enzyme immunoassay for detection of DDT

Dichlorodiphenyltrichloroethane (DDT) is one of the persistent organic pollutants (POPs) widely found in the environment and in the general population. In this study, a direct competitive enzyme immunoassay (EIA) has been developed for the quantitative analysis of DDT. To generate a specific polyclonal antibody for EIA, p, p'-DDT was conjugated to porcine thyroglobulin for rabbit immunization. At optimized EIA conditions, the standard curves ranged from 0.137 to 100 ng/mL with the quantification limit of 0.41 ng/mL. The coefficients of variation (CV%) were 5.42-10.53% for intra-assay and 6.04-7.26% for inter-assay. Cross-reactivities with DDT metabolites (DDTs, including o, p'-DDT, p, p'-DDD, o, p'-DDD, p, p'-DDE, o, p'-DDE, p, p'-dichlorobenzophenone (DCBP), o, p'-DCBP) were investigated. The polyclonal antibody showed relatively low and/or no cross-reactivity with these compounds, and the assay was seen to be highly selective for p, p'-DDT. Moreover, the DDTs could be ranked by their reactivity: DDT > DDD > DDE > DCBP. In addition, the characterization of the polyclonal antibody indicated that the antiserum possesses a high specificity for p, p'-isomers. The results indicated that the developed EIA using this antibody could be a convenient and supplemental analytical tool for monitoring DDT.