Photocatalytic mineralization of hydroperfluorocarboxylic acids with heteropolyacid H₄SiW₁₂O₄₀ in water

The decomposition of hydroperfluorocarboxylic acids [H-PFCAs; HC_nF_2nCOOH (n = 4 and 6)] induced by heteropolyacid photocatalyst H₄SiW₁₂O₄₀ in water was investigated, and the results are compared with the results for the corresponding perfluorocarboxylic acids (PFCAs; C_nF_2n+1COOH). This is the first report on the photochemical decomposition of H-PFCAs, which are being developed as alternative surfactants to environmentally persistent and bioaccumulative PFCAs. H-PFCAs were not decomposed by irradiation with UV-Visible light (>290 nm) in the absence of H₄SiW₁₂O₄₀. In contrast, UV-Visible light irradiation of H-PFCAs in the presence of H₄SiW₁₂O₄₀ efficiently decomposed H-PFCAs to F⁻ and CO₂. The decomposition reactions showed pseudo-first-order kinetics, and the decomposition rate constants were 1.8-2.5 times higher than those for the corresponding PFCAs. The reaction mechanism can be explained by elimination of H⁺ from the ω-H atom of the H-PFCAs by the excited catalyst, followed by formation of perfluorodicarboxylic acids.     

Global-scale quantitative assessment for biodiversity on forest land use: applying the Global No Net Loss approach

Here we propose a method to quantitatively assess and examine Global No Net Loss (GNNL) of forest biodiversity on a global scale. The method produces a GNNL index of existing forest and enables future predictions of forest loss under different assumptions. The method tests the feasibility of the GNNL index and enables discussion of policy for future global scale sustainable forest management up to 2050. The GNNL index was estimated from an equation including forest areas per country per forest type (primary forest, secondary forest and plantation forest), diversity of forest ecosystem, and species density. Estimates derived from historical data revealed an approximate 7% reduction in GNNL index between 1990 and 2005. Predictions of the GNNL index until 2050 emphasize the importance of regenerating large portions of forests felled for agricultural land (or other uses) with secondary forests.     

Relationship between dietary exposure and serum perfluorochemical (PFC) levels—A case study

Daily dietary intake of perfluorinated chemicals (PFCs) in relation to serum levels was assessed by determination of nine PFCs including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in matched daily diet duplicates and serum samples. Diet and serum were collected in year 2004 from 20 women in Osaka and Miyagi, Japan. Only PFOS and PFOA were detected in the diet samples and no significant difference between cities was seen. After adjusted by water content, diet concentration of PFOA was significantly higher in Osaka. The median daily intake calculated using the measured diet concentrations was 1.47 ng PFOS/kg b.w. and 1.28 ng PFOA/kg b.w. for Osaka, and 1.08 ng PFOS/kg b.w. and 0.72 ng PFOA/kg b.w. for Miyagi. A significant difference between cities was seen for the serum concentrations with median of 31 ng/mL PFOS and PFOA in Osaka, compared to 14 ng/mL PFOS and 4.6 ng/mL PFOA in Miyagi. Carboxylates such as perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUnDA) were also detected in serum at median levels 6.9 ng/mL and 3.2 ng/mL (Osaka), and 2.8 ng/mL and 5.1 ng/mL (Miyagi). Based on one-compartment model under steady state, dietary intake of PFOS and PFOA accounted for only 22.4% and 23.7% of serum levels in Osaka females, and in contrast 92.5% and 110.6% in Miyagi females, respectively.     

Improvement of permeability of waste sludge by mixing with slag or construction and demolition waste

To determine the allowable ratio of waste sludge required to ensure an aerobic zone in the landfill, we investigated sludge permeability, which involved mixing sludge, the major landfill waste in Japan, at different mixing ratios with other wastes (slag and construction and demolition waste (C&D)). We measured parameters of sample permeability and analyzed parameters that exert a large influence on oxygen penetration depth with a simulation model accounting for both diffusion and convection driven by temperature gradients. We also determined the critical volumetric contents in which gas and/or water permeability change significantly when sludge is mixed with sand or gravel. From the results of the simulations, gas permeability of the layer, the difference between inside and outside temperatures and the oxygen consumption rate exert a large influence on the resulting oxygen penetration depth. The allowable ratio of sludge required to ensure an aerobic zone in the landfill was determined by considering the balance of the above three parameters. By keeping volumetric sludge content to below 25%, air convection and oxygen penetration depth of several meters were achieved in the modeling.     

Air Quality Standards National And International

The advantages and disadvantages of establishingworldwide air quality standards are reviewed. Inter-national standards would represent the best and mostadvanced procedures and might lead to improvementin standards in some countries where air quality isfar from adequate. International standards alsowould permit accurate comparisons of air pollutionamong countries and would provide a sound basis forcombatting pollution.     

Microalgae cultured by sewage and organic constituents

The microalgae could be multiplied by supplying only sewage influent or effluent without any additional microalgal stock or nutrient salt. In a semicontinuous culture, the N:P weight ratios consumed were 14:1 and 18:1 for the sewage influent and effluent, respectively. The total cell number and green algae ratio of microalgae cultivated by semicontinuous culture exceeded those of batch culture. No cyanobacterial cells were observed in the semicontinuous culture using the sewage effluent. The organic components in the cultured microalgae using sewage effluent, eluted by n-hexane, were determined. The ratio of unsaturated fatty acid exceeded that of saturated fatty acid, which was possibly attributable to the fluidity of the cell membrane. The squalene was also obtained by the culture using sewage alone, free of any external stock or nutrient salt. The higher heating value of the microalgae of semicontinuous culture using the sewage influent was 25 MJ kg⁻¹, corresponding to the heating value of lignite and showing the potential of the sewage culture microalgae as a means of power generation and combustion aid.     

Current levels of airborne polyfluorinated telomers in Japan

Fluorotelomer alcohols (FTOHs), a class of per- and poly-fluorochemicals (PFCs), are environmental contaminants characterized by high volatility and are therefore prone to long-range atmospheric transport. In this study, airborne FTOHs were identified in Japan using a newly developed passive air sampler containing activated carbon felts. Air sampling was conducted at 33 sites all over Japan from April to June 2007. 8:2 FTOH, the dominant analyte, ranged from <32 to 2466pgm(-3) (mean: 241pgm(-3)) followed by 6:2 FTOH from n.d. to 768pgm(-3) (mean: 51.6pgm(-3)), 10:2 FTOH from <17 to 113pgm(-3) (mean: 26.8pgm(-3)) and 8:2 FTOAcryl from n.d. to 480pgm(-3) (mean: 25.8pgm(-3)). 8:2 FTOMethacryl was not detected above detection limit (3pgm(-3)) in all samples. The highest concentration of total investigated PFCs was found in Chiba (35 degrees 43'20' N 140 degrees 39'46' E) (2152-3181pgm(-3)). On the other hand, in three locations of Higashi-Yodogawa (34 degrees 44' N 135 degrees 32' E), high levels of 8:2 FTOAcryl (239pgm(-3), 109-480pgm(-3)) were detected, the levels of which were comparable to those of 8:2 FTOH (mean: 175pgm(-3), range: 115-292pgm(-3)). This study is the first national wide-scale survey of FTOHs and 8:2 FTOAcryl across Japan, showing that 8:2 FTOH was ubiquitous in the environment in Japan.     

Distribution and temporal changes of lead in the surface seawater in the western Pacific and adjacent seas derived from coral skeletons

We determined Pb contents together with Pb isotopic compositions in coral skeletons (Porites spp.) collected from the western Pacific and adjacent seas to examine distribution of Pb in sea surfaces. Temporal records of Pb were also investigated using coral skeletons from Hainan and Ogasawara Island, located in China and Japan, respectively. The spatial distribution of Pb showed a clear dilution pattern of Pb from Asian continent to the open ocean. Also the similar trend was found in the Java Sea from Jakarta to the offshore. In addition to the spatial distribution, Pb contents in Ogasawara coral have gradually increased during last 108 years. It may be attributed to Pb emission mainly from industrial activities in Asian countries. Hainan coral, which provided 10 years record of Pb, showed a remarkable decline around 1997 probably due to the partial introduction of unleaded gasoline in China.     

Global Warming: Risk Perception and Risk-Mitigating Behavior in Japan

Global warming is a major concern for the Japanese public. However, because the influence of global environmental risks, particularly global warming, is long-term and widespread, it seems difficult for the public to recognize it as a familiar and important problem that necessitates firm action. This study attempts to determine the causal structure promoting risk-mitigating behavior with regard to global warming, using Covariance Structure Analysis (CSA) with data from a survey of a subset of the Japanese population. We model the causal structure promoting risk-mitigating behavior population. There are four main stages in the process of decision-making for and values, risk perception, mitigating behavior intention, and personal environmental policies has three stages: concerns and values, risk perceptions, ectively accelerate the public’s participation in policy decisions, by translating their risk-mitigating into practical actions. Increased knowledge through improved access should improve the interaction between the public and environmental policy-makers with regard to global warming, using CSA with data from a survey of a subset of the Japanese personal actions: concerns actions. Support for andmitigating behavior intentions. Our results suggest that improved access to information concerning the risks associated with global warming in particular, and environmental issues in general, will be sufficient to effintentions for to information in Japan.     

MODELING FLOOD DAMAGE: CASE OF TOKAI FLOOD 20001

ABSTRACT: In conventional flood damage reduction studies, flood damage is usually estimated with a damage function according to the depth of inundation. However, this method may not reflect the conditions of each family residing in the floodplain because it ignores not only the distribution of flood damage but also the effect of building characteristics and residents' preparedness. This paper uses data from a questionnaire based survey (N= 3,036) conducted 17 months after the Tokai Flood of 2000 that caused disastrous losses to household properties. It provides a conceptual “doughnut structure” model of flood damage to houses and house contents and a mathematical basis for models to explore the determinants of flood damage. Besides the inundation depth, house type significantly affects both the house structural and content damage probabilities, while house ownership and house structure affect house damage probability but not house content damage probability at a given depth. Inundation depth, residing period, and household income significantly affect both house and content damage values. In addition, house ownership has a significant impact on the house damage value, while house structure has an impact on content damage value.