Short-time exposure to mono-n-butyl phthalate (MBP)-induced oxidative stress associated with DNA damage and the atrophy of the testis in pubertal rats

Phthalates are widely used as plasticizer in various consumer domestic products and are known to disturb the male reproductive function in rodents. This study investigated the involvement of oxidative stress and the atrophy of the testes in pubertal rats exposed to mono-n-butyl phthalate (MBP). Four-week-old pubertal male rats were separated into three groups. In group I, 21 rats were fed rat chow containing 2 % MBP for 3 days. In group II, 21 rats were fed rat chow containing 2 % MBP for 3 days and antioxidant vitamins C (250 mg/kg/day) and E (50 mg/kg/day) were injected daily. In group III, 21 rats were fed standard rat chow and used as controls. After 3 days, each testis was weighed and the germ cell development was evaluated using the Johnsen score. The urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels were measured as a biological marker of oxidative DNA damage. The mean testis weight was significantly lower for group I than groups II or III (p?<?0.05). The mean Johnsen score was significantly lower for group I than for groups II or III (p?<?0.05). Urinary 8-OHdG concentrations were higher in group I than in groups II or III. Short-time exposure to MBP may therefore induce oxidative DNA damage in rat testes, while antioxidant vitamins administered during exposure may protect against this stress.     

Comparative study on indoor air quality in Japan and China: Characteristics of residential indoor and outdoor VOCs

We conducted a comparative study on the indoor air quality for Japan and China to investigate aromatic volatile organic compounds (VOCs) in indoor microenvironments (living room, bedroom, and kitchen) and outdoors in summer and winter during 2006–2007. Samples were taken from Shizuoka in Japan and Hangzhou in China, which are urban cities with similar latitudes. Throughout the samplings, the indoor and outdoor concentrations of many of the targeted VOCs (benzene, toluene, ethylbenzene, xylenes, and trimethylbenzenes) in China were significantly higher than those in Japan. The indoor concentrations of VOCs in Japan were somewhat consistent with those outdoors, whereas those in China tended to be higher than those outdoors. Here, we investigated the differences in VOC concentrations between Japan and China. Compositional analysis of indoor and outdoor VOCs showed bilateral differences; the contribution of benzene in China was remarkably higher than that in Japan. Significant correlations (p < 0.05) for benzene were observed among the concentrations in indoor microenvironments and between the outdoors and living rooms or kitchens in Japan. In China, however, significant correlations were observed only between living rooms and bedrooms. These findings suggest differences in strengths of indoor VOC emissions between Japan and China. The source characterizations were also investigated using principal component analysis/absolute principal component scores. It was found that outdoor sources including vehicle emission and industrial sources, and human activity could be significant sources of indoor VOC pollution in Japan and China respectively. In addition, the lifetime cancer risks estimated from unit risks and geometric mean indoor concentrations of carcinogenic VOCs were 2.3 × 10^?5 in Japan and 21 × 10^?5 in China, indicating that the exposure risks in China were approximately 10 times higher than those in Japan.     

Environmental assessment and accounting for the waste disposal stream in Bangkok,Thailand

It is very important that waste should be controlled and appropriately handled in a waste disposal stream, considering its impact on the environment. In this research, the LCA-EA model was applied to the current waste disposal stream of the BMR as well as other waste disposal stream scenarios, so that treatment cost, environmental load and environmental cost were assessed quantatively. The results of this study showed that in the current waste diposal stream in Bangkok, there were large contributions from carbon dioxide and methane to the greenhouse gas emissions from the stream. The study was able to quantify the reductions in environmental load associated with various waste disposal stream scenarios, using the baseline scenario as a standard.     

Attenuation of lead leachability in shooting range soils using poultry waste amendments in combination with indigenous plant species

Chemical immobilization technology utilizing poultry waste (PW) along with a native plant (Panicum maximum Jacq.) application was assessed for the attenuation of downward Pb dissolution and modification of Pb speciation in solid and liquid phases in the soil. A large column study with and without plant and PW applications was conducted using a Pb contaminated soil collected from a shooting range area. The PW application reduced water-extractable Pb by about 43% of that of the treatment without the PW and plant applications (Control). The cumulative Pb amount in column leachates over 100d was increased by the PW amendment (0.32mg) compared to Control (0.27mg), but was reduced to 0.23mg by the combined use of plant and PW amendment. Sequential extraction analysis revealed that the Pb fractions of PW-amended soils were shifted to less soluble phases as indicated by an increased residual fraction (20%) and decreased exchangeable and carbonate fractions (22%) than those in the Control soil. Thermodynamic equilibrium calculations demonstrated that predicted Pb(2+) activity was saturated with respect to cerussite in the Control soil and was supersaturated with respect to chloropyromorphite in the PW-amended soils. Our results suggest that the use of plant in combination with PW as a Pb immobilizing amendment attenuated downward Pb leaching and altered Pb species to more geochemically stable phases.     

Prospects for cost-effective post-combustion CO2 capture from industrial CHPs

Industrial Combined Heat and Power plants (CHPs) are often operated at partial load conditions. If CO₂ is captured from a CHP, additional energy requirements can be fully or partly met by increasing the load. Load increase improves plant efficiency and, consequently, part of the additional energy consumption would be offset. If this advantage is large enough, industrial CHPs may become an attractive option for CO₂ capture and storage CCS. We therefore investigated the techno-economic performance of post-combustion CO₂ capture from small-to-medium-scale (50–200 MWe maximum electrical capacity) industrial Natural Gas Combined Cycle- (NGCC-) CHPs in comparison with large-scale (400 MWe) NGCCs in the short term (2010) and the mid-term future (2020–2025). The analyzed system encompasses NGCC, CO₂ capture, compression, and branch CO₂ pipeline.The technical results showed that CO₂ capture energy requirement for industrial NGCC-CHPs is significantly lower than that for 400 MWe NGCCs: up to 16% in the short term and up to 12% in the mid-term future. The economic results showed that at low heat-to-power ratio operations, CO₂ capture from industrial NGCC-CHPs at 100 MWe in the short term (41–44 €/tCO₂ avoided) and 200 MWe in the mid-term future (33–36 €/tCO₂ avoided) may compete with 400 MWe NGCCs (46–50 €/tCO₂ avoided short term, 30–35 €/tCO₂ avoided mid-term).     

Transepithelial transport and cellular accumulation of steroid hormones and polychlorobiphenyl in porcine kidney cells expressed with human P-glycoprotein

Endocrine disrupters such as sex hormone-like chemicals and the non-physiological ligands for aryl hydrocarbon receptor (AhR) exert many adverse biological effects. The ligands for AhR disturb gene expression downstream of the gene induced by estrogen receptor at a very low concentration. Thus, transepithelial transport and cellular accumulation of cortisol (COR) and estrogen as congeners of sex hormone-like chemicals, and 3,3^′,4,4^′-tetrachlorobiphenyl (TeCB) as one of the ligands for AhR were examined in a monolayer of porcine kidney cells transfected with human P-glycoprotein (LLC-COL). The net basal-to-apical transport of COR increased in LLC-COL compared to that in the wild type cells (LLC-PK1) the same as in vinblastine, whereas the net transport of estradiol (EST) was not detected in either cell group. Though the diffusion transports of EST for both directions, basal-to-apical and apical-to-basal, were higher than that of COR, cellular accumulation of EST was higher than that of COR. Transepithelial transport of TeCB was very low and the net basal-to-apical transport was not detected, while it was highly accumulated in the epithelial cells. The accumulation was slightly higher in LLC-COL than in LLC-PK1 at high dose.     

Simultaneous determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons in emissions from the scorching of polyvinylidene chloride film

An analytical method for the determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons (ClPAHs) was investigated. By means of this method, concentrations and isomer profiles of the 27 target ClPAHs could be analyzed. To evaluate the usefulness of the method for analyzing ClPAH emissions, laboratory-scale scorching tests were performed on polyvinylidene chloride (PVDC) plastic wrap over a flame of the gas burner. Only seven of the target ClPAHs were detected, and all compounds detected had 2, 3, or 4 rings. The detected ClPAHs were present in both the particulate phase and the gaseous phase, but they were present at higher concentrations in the gaseous phase than in the particulate phase. Relationships between the number of chlorine substituents on the naphthalene/phenanthrene rings and the overall concentration and the percentage in the particulate phase were also investigated.     

Effects of parabens on apoptosis induced by serum-free medium

Alkyl esters of p-hydroxybenzoic acids (parabens), an endocrine disrupter, are used as preservatives in cosmetics and foods. In this study, to understand the relationship between parabens and differentiation in infants, the effects of parabens on apoptosis induced by serum deprivation in PC12 cells were investigated. In addition, apoptosis-related factors were assayed. As results, a tendency toward enhancement of apoptosis was observed in the cells cultured in the serum-free medium with methylparaben, and this tendency was suggested to be related to the contents of BAD, a pro-apoptotic protein. Butylparaben did not show any tendency to enhance apoptosis.