Respiratory uptake kinetics of neutral hydrophobic organic chemicals in a marine benthic fish, Pseudopleuronectes yokohamae

We investigated the respiratory uptake kinetics of polychlorinated biphenyls (PCBs), organohalogen pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs), and 2,2′,4,4′-tetrabrominated diphenyl ether (BDE #47) in a marine benthic fish, Pseudopleuronectes yokohamae. The respiratory uptake efficiencies (E_W) of the chemicals, of which there have been no reports for the majority of persistent organic pollutants (POPs), were obtained by measuring the respiratory uptake rate constants (k₁) and the oxygen consumption rates of fish. Fish were exposed to water in which these chemicals were dissolved at environmentally relevant concentrations for 28 d, followed by 168 d of depuration in clean seawater. The k₁ and E_W values for 99 compounds were obtained, and they ranged from 2000 to 42 000 L kg-lipid⁻¹ d⁻¹ and from 0.060 to 1.3, respectively. The E_W values of the chemicals, except for PAHs, tended to increase with increasing values of the log octanol–water partition coefficients (K_OW) of the chemicals up to a log K_OW of 5. For log K_OW in the range 3–5, the E_W values in this study were much lower than those in a published study (about one-third). As a result of analysis by a two-phase resistance model, the resistance of transport rates to the lipid phase in this study was lower than was the case in the published study. These findings indicate that the E_W predicted by the published study for log K_OW in the range 3–5 may differ among fish species and water temperature, and further study is needed.     

Evaluating the cost of flood damage based on changes in extreme rainfall in Japan

We estimated the cost of flood damage using numerical simulations based on digital map data and the flood control economy investigation manual submitted by the Ministry of Land, Infrastructure, Transportation, and Tourism in Japan. The simulation was carried out using a flood model incorporating representative precipitation data for all of Japan. The economic predictions, which estimate flood damage caused by extreme rainfall for the return periods of 5, 10, 30 50, and 100 years, are as follows: (1) the cost of flood damage increases nearly linearly with increases in extreme precipitation; (2) assuming that flood protection is completed for a 50-year return period of extreme rainfall, the benefit of flood protection for a 100-year return period of rainfall is estimated to be 210 billion USD; (3) the average annual expected damage cost for flooding is predicted to be approximately 10 billion USD per year, based on the probability of precipitation for a return period of 100 years and assuming that flood control infrastructures will be completed within the 50-year return period and will be able to protect from flooding with a 50-year return period; (4) urban and rural areas are predicted to suffer high and low costs of damage, respectively. These findings will help to derive measures to enhance flood protection resulting from climate change.     

Evaluation of electronic components in life cycle assessment

Life cycle assessment (LCA), a quantitative method for evaluating the total environmental impact of a product, from the materials in its manufacture to its final disposal, is playing an increasingly important role in manufacturing. When the LCA method is applied to a product containing many kinds of electronic components, there is a need for life cycle inventory (LCI) data on the components. This paper provides an original calculation of the LCI data for each electronic components industry. These data show the amount of input energy and emissions into the atmosphere per yen of production yield. It is demonstrated that the magnitude of the LCI data for each industry is essentially equal to that of the other industries. Furthermore, we conclude that the LCI data for all electronic components are roughly equivalent, making it possible to calculate the LCI data of any electronic component by simply multiplying the LCI data for the industry by the price of the component. Furthermore, after comparing the materials production stages with the component manufacturing stage in the calculation, it became clear that for several component industries the materials production stage could not be omitted from the calculation. Received: April 10, 1998 / Accepted: February 8, 1999     

Spawning migration and returning behavior of white-streaked grouper Epinephelus ongus determined by acoustic telemetry

White-streaked grouper (Epinephelus ongus) is an important fishery target that forms fish spawning aggregations (FSAs) at specific spawning grounds. The aims of the present study were to investigate migration behavior and returning behavior in terms of FSA using acoustic telemetry. Among the 30 specimens tracked, three types of movement pattern were observed: type 1, high site fidelity at the release area before the spawning period, migration to the spawning ground during the spawning period and return to the release area just after the spawning period (17 specimens); type 2, high site fidelity at the release area, disappearance from the area during the spawning period but was not detected at the spawning ground and return to the release area (8 specimens); and type 3, high site fidelity at the release area was observed before, during and after the spawning period (5 specimens). For the 17 specimens that were categorized into type 1, the dates of departure from their release area and the dates of return to the release area of males were, respectively, significantly earlier and later than those of females. The duration between the departure date and the return date (“duration away”) of males was significantly longer than that of females. The duration away tended to be positively related to the condition factor. All 25 specimens that were categorized as type 1 and type 2 showed returning behaviors to the release area.     

Mass spectrometric study of secondary organic aerosol formed from the photo-oxidation of aromatic hydrocarbons

From measurements by an Aerodyne Aerosol Mass Spectrometer (AMS), secondary organic aerosol (SOA) formed in laboratory chambers is believed to be less oxidized than well-oxidized ambient organic aerosol (OA). However, the mass spectrum of SOA formed from the photo-oxidation of aromatic hydrocarbons has not been sufficiently studied by using AMS though these reactions are potential sources of urban SOA. In this study, we studied SOA formed from the photo-oxidation of seven aromatic hydrocarbons by using Time-of-Flight AMS. Strong mass signals from SOA were found at m/z 43 (m43) and 44 (m44) in all the experiments. The m44 to total organic aerosol mass ratio (m44/OA) increased with irradiation time. For example, the m44/OA ratio increased from 10.6% to 13.3% during irradiation for 11 h in an experiment with toluene. The average m44/OA ratios were determined to be 5.8–17.1% for all the experiments. The m44/OA decreased and the m43/OA increased with increasing number of alkyl substituents of precursor aromatic hydrocarbons. This is because low-reactive ketones are preferentially produced rather than aldehydes with increasing number of alkyl substituents. The m44/OA ratios of the benzene and monoalkylbenzene oxidation were 12.2–17.1% and were close to those of well-oxidized ambient OA. These findings are consistent with the hypothesis that the photo-oxidation of aromatic hydrocarbons is a potential source of urban SOA. In addition to oxygenated organic compounds, organic nitrogen oxides were also shown to be present in SOA by high-resolution mass spectra.     

Age-Dependent Factors Affecting Thoracic Response: A Finite Element Study Focused on Japanese Elderly Occupants

Objectives: The ultimate goal of this research is to reduce thoracic injuries due to traffic crashes, especially in the elderly. The specific objective is to develop and validate a full-body finite element model under 2 distinct settings that account for factors relevant for thoracic fragility of elderly: one setting representative of an average size male and one representative of an average size Japanese elderly male.

Methods: A new thorax finite element model was developed from medical images of a 71-year-old average Japanese male elderly size (161cm, 60 kg) postmortem human subject (PMHS). The model was validated at component and assembled levels against original series of published test data obtained from the same elderly specimen. The model was completed with extremities and head of a model previously developed. The rib cage and the thoracic flesh materials were assigned age-dependent properties and the model geometry was scaled up to simulate a 50th percentile male. Thereafter, the model was validated against existing biomechanical data for younger and elderly subjects, including hub-to-thorax impacts and frontal impact sled PMHS test data. Finally, a parametric study was conducted with the new models to understand the effect of size and aging factors on thoracic response and risk of rib fractures.

Results: The model behaved in agreement with tabletop test experiments in intact, denuded, and eviscerated tissue conditions. In frontal impact sled conditions, the model showed good 3-dimensional head and spine kinematics, as well as rib cage multipoint deflections. When properties representative of an aging person were simulated, both the rib cage deformation and the predicted number of rib fractures increased. The effects of age factors such as rib cortical thickness, mechanical properties, and failure thresholds on the model responses were consistent with the literature. Aged and thereby softened flesh reduced load transfer between ribs; the coupling of the rib cage was reduced. Aged costal cartilage increased the severity of the diagonal belt loading sustained by the lower loaded rib cage.

Conclusions: When age-specific parameters were implemented in a finite element (FE) model of the thorax, the rib cage kinematics and thorax injury risk increased. When the effect of size was isolated, 2 factors, in addition to rib material properties, were found to be important: flesh and costal cartilage properties. These 2 were identified to affect rib cage deformation mechanisms and may potentially increase the risk of rib fractures.     

Future-year ozone prediction for the United States using updated models and inputs

The relationship between emission reductions and changes in ozone can be studied using photochemical grid models. These models are updated with new information as it becomes available. The primary objective of this study was to update the previous Collet et al. studies by using the most up-to-date (at the time the study was done) modeling emission tools, inventories, and meteorology available to conduct ozone source attribution and sensitivity studies. Results show future-year, 2030, design values for 8-hr ozone concentrations were lower than base-year values, 2011. The ozone source attribution results for selected cities showed that boundary conditions were the dominant contributors to ozone concentrations at the western U.S. locations, and were important for many of the eastern U.S. locations. Point sources were generally more important in the eastern United States than in the western United States. The contributions of on-road mobile emissions were less than 5 ppb at a majority of the cities selected for analysis. The higher-order decoupled direct method (HDDM) results showed that in most of the locations selected for analysis, NOx emission reductions were more effective than VOC emission reductions in reducing ozone levels. The source attribution results from this study provide useful information on the important source categories and provide some initial guidance on future emission reduction strategies.

Implications: The relationship between emission reductions and changes in ozone can be studied using photochemical grid models, which are updated with new available information. This study was to update the previous Collet et al. studies by using the most current, at the time the study was done, models and inventory to conduct ozone source attribution and sensitivity studies. The source attribution results from this study provide useful information on the important source categories and provide some initial guidance on future emission reduction strategies.     

Pyrosequencing Analysis of Norovirus Genogroup II Distribution in Sewage and Oysters: First Detection of GII.17 Kawasaki 2014 in Oysters

Norovirus GII.3, GII.4, and GII.17 were detected using pyrosequencing in sewage and oysters in January and February 2015, in Japan. The strains in sewage and oyster samples were genetically identical or similar, predominant strains belonging to GII.17 Kawasaki 2014 lineage. This is the first report of GII.17 Kawasaki 2014 in oysters.