Impact of fermented brown rice with Aspergillus oryzae (FEBRA) intake and concentrations of polybrominated diphenylethers (PBDEs) in blood of humans from Japan

The isotope dilution technique was applied for the analysis of new polybrominated diphenylethers (PBDEs) calibration standard (both labeled and non-labeled) using high-resolution gas chromatography-high-resolution mass spectrometry (HRGC-HRMS). The relative response factor (RRF) and relative standard deviation (RSD) for new calibration standard in Finnigan Thermo Electron (MAT-95XL) and Micromass (Autospec Ultima) were more or less identical with mean RRF (0.9882), RSD (0.0865) and CV% of (8.75). The results also revealed for DeBDE-209 quantification; labeled DeBDE-209 is essential. Furthermore, we recommend on column injection technique with a thin film instead of splitless injection in order to reduce the thermal degradation of DeBDE-209 and formation of octabromodibenzofurans (OBDF). Besides, analysis of human blood (n = 156) of FEBRA-intake and non-FEBRA-intake individuals elucidated frequent detection of eighteen PBDE congeners. The average PBDE concentrations in non-FEBRA intake and FEBRA-intake humans were 6000-11,000 (mean: 8400) and 5400-15,000 (mean: 9900) respectively on pg/g fat basis. Although FEBRA-intake individuals showed slightly greater PBDEs, computer-normalized concentrations of TeBDE-47 corroborate FEBRA-intake individual from four family showed reduced concentrations. The contamination profiles of PBDEs varied in between family, gender as well as geography. International comparison with predominant PBDE congener (TeBDE-47) prevailed lower levels in Japan when compared to Korea, Germany and USA nevertheless, congener specific profiles were different which is in accordance with different technical PBDE usage in between countries.     

Performance tests of newly developed adsorption/plasma combined system for decomposition of volatile organic compounds under continuous flow condition

The adsorption/plasma decomposition with the combination of adsorption honeycomb-sheets and a plasma element is a new technology for small-sized apparatuses to decompose volatile organic compounds (VOCs) at concentrations lower than about 100 ppm. The feasibility of the prototype adsorption/plasma decomposition apparatus was evaluated with the simulated exhausts containing one VOC component and with real exhausts from a painting booth and an adhesion factory. The apparatus decomposed VOCs e ectively at the painting booth exhaust but not always satisfactorily at the adhesion factory exhaust. The performance test results with real exhausts were discussed with respect to the concentration and discharge pattern of the exhausts and the basic properties of the system such as cooperation of adsorption and plasma reaction and the concentration dependence of the performance.     

Japanese Papilio butterflies puddle using Na+ detected by contact chemosensilla in the proboscis

Many butterflies acquire nutrients from non-nectar sources such as puddles. To better understand how male Papilio butterflies identify suitable sites for puddling, we used behavioral and electrophysiological methods to examine the responses of Japanese Papilio butterflies to Na⁺, K⁺, Ca²⁺, and Mg²⁺. Based on behavioral analyses, these butterflies preferred a 10-mM Na⁺ solution to K⁺, Ca²⁺, and Mg²⁺ solutions of the same concentration and among a tested range of 1?mM to 1?M NaCl. We also measured the ion concentrations of solutions sampled from puddling sites in the field. Na⁺ concentrations of the samples were up to 6?mM, slightly lower than that preferred by butterflies in the behavioral experiments. Butterflies that sipped the 10?mM Na⁺ solution from the experimental trays did not continue to puddle on the ground. Additionally, butterflies puddled at sites where the concentrations of K⁺, Ca²⁺, and/or Mg²⁺ were higher than that of Na⁺. This suggests that K⁺, Ca²⁺, and Mg²⁺ do not interfere with the detection of Na⁺ by the Papilio butterfly. Using an electrophysiological method, tip recordings, receptor neurons in contact chemosensilla inside the proboscis evoked regularly firing impulses to 1, 10, and 100?mM NaCl solutions but not to CaCl₂ or MgCl₂. The dose?Cresponse patterns to the NaCl solutions were different among the neurons, which were classified into three types. These results showed that Japanese Papilio butterflies puddle using Na⁺ detected by the contact chemosensilla in the proboscis, which measure its concentration.     

Analysis of COVID-19 waste management in Vietnam and recommendations to adapt to the ‘new normal’ period

Journal of Material Cycles and Waste Management - Amid the 4th wave of COVID-19, Vietnam reopened its economy, which placed extra burdens on the COVID-19 waste management system. This study...     

Response of spinach and komatsuna to biogas effluent made from source-separated kitchen garbage

Recycling of kitchen garbage is an urgent task for reducing public spending and environmental burdens by incineration and/or landfill. There is an interesting regional effort in Ogawa, Saitama prefecture, Japan, in which source-separated kitchen garbage is anaerobically fermented with a biogas plant and the resultant effluent is used as a quick-release organic fertilizer by surrounding farmers. However, scientific assessments of fertilizer values and risks in the use of the effluent were lacking. Thus, a field experiment was conducted from 2003 to 2004 in Tohoku National Agricultural Research Center to grow spinach (Spinacia oleracea L.) and komatsuna (Brassica rapa var. perviridis L. H. Bailey) for evaluating the fertilizer value of the kitchen garbage effluent (KGE), nitrate, coliform group (CG), Escherichia coli, fecal streptococci (FS), and Vibrio parahaemolyticus concentrations of KGE and in the soil and the plant leaves. A cattle manure effluent (CME) and chemical fertilizers (NPK) were used as controls. Total nitrogen (N) and ammonium N concentrations of the KGE were 1.47 and 1.46 g kg(-1), respectively. The bacteria tested were detected in both biogas effluents in the order of 2 to 3 log CFU g(-1), but there was little evidence that the biogas effluents increased these bacteria in the soil and the plant leaves. At the rate of 22 g N m(-2), yield, total N uptake, apparent N recovery rate, and leaf nitrate ion concentration at harvest of spinach and komatsuna in the KGE plot were mostly comparable to those in the NPK and CME plots. We conclude that the KGE is a quick-release N fertilizer comparable to chemical fertilizers and does not cause contamination of CG, E. coli, FS, or V. parahaemolyticus in the soil and spinach and komatsuna leaves.     

Validation of diffusive mini-samplers for aldehyde and VOC and its feasibility for measuring the exposure levels of elementary school children

Exposure to various chemicals can cause adverse effects to health, such as asthma and allergies, especially in children. Data on personal exposure levels in children are scarce, thus small lightweight diffusive mini-samplers for aldehydes and volatile organic compounds (VOCs) were designed to measure the exposure level of children to these chemicals. The aim of the study was to validate and examine the applicability of these mini-samplers for measuring daily chemical exposure. The diffusive mini-samplers are 20 mm in length, 11 mm in diameter, and 1.67 g in weight. The devices are cylindrically shaped with polytetrafluoroethylene membrane filters placed at each end. To measure aldehydes and acetone, 20 mg of 2,4-dinitrophenylhydrazine was used as an absorbent. To measure VOCs, a carbon molecular sieve was used. The sampling rate for each chemical was determined by parallel sampling with active samplers in a closed exposure bag. The blank levels of the chemicals and the storage stability of the device were tested. The mini-samplers were compared to commercially available diffusive samplers. To examine the applicability of the samplers, 65 elementary school children carried them for 24 h. The sampling rates for formaldehyde, acetaldehyde, and acetone were 20.9, 22.9, and 19.7 mL min(-1), respectively. The limits of quantification (LOQ) for the 24-hour sampling by high-performance liquid chromatography/ultraviolet (HPLC/UV) analysis were 8.3, 7.6, and 8.8 μg m(-3) for formaldehyde, acetaldehyde, and acetone, respectively. The sampling rates for the 11 VOCs were determined and ranged from 3.3 mL min(-1) for styrene and 2-ethyl-1-hexanol to 11.7 mL min(-1) for benzene. The LOQ for the 24-hour sampling by gas chromatography-mass spectrometry (GC-MS) analysis ranged from 5.9-105.2 μg m(-3), 1.1-24.7 parts per billion. The storage stability after 5 days ranged from 94.8 to 118.2%. Formaldehyde, acetone, benzene, and toluene were detected above the LOQ in more than 90% of the children, and the median concentrations were 21.7, 20.9, 10.1, and 21.5 μg m(-3), respectively. This study shows that the diffusive samplers developed were suitable for children to carry and were capable of measuring the children's daily chemical exposure.     

Seasonal variation in the acute effects of ozone on premature mortality among elderly Japanese

We conducted a multicity time-series study using monitoring data to assess seasonal patterns of short-term ozone–mortality association among elderly aged 65 years and over in Japan. Daily exposure to ambient ozone was computed using hourly measurements of photochemical oxidants available at multiple monitoring stations in each city. Effects of ozone on daily all-cause non-accidental, cardiovascular, and respiratory mortality were estimated using distributed lag linear models, controlling for confounding by temporal, day of the week, temperature, and flu epidemics. City-level effect estimates were combined using inverse variance meta-analysis. In spring and autumn, a 10-ppbv increase of daily maximum 8-h average ozone concentration in the previous 3 days was associated with 0.69 % (95 % confidence interval (CI): 0.27–1.10), 1.07 % (0.34–1.82), and 1.77 % (0.78–2.77) increases in daily all-cause, cardiovascular, and respiratory mortality, respectively. Forward displacement of respiratory mortality was large during the cold season despite lower ozone concentration. Results were generally independent of fine particulate matter and nitrogen dioxide. Findings suggest significant mortality effects of short-term ozone exposure among the elderly during the moderate season. Those with underlying respiratory diseases were susceptible, even during winter.     

Composting of food refuse from a student restaurant in Hokkaido University

Over a period of 21 months, we composted food refuse from a student restaurant in Hokkaido University using a commercially available composting machine. The machine had two reactors, each with a working volume of 250 l. The refuse was mixed with sawdust in a ratio of 5 l sawdust to 10 kg refuse, and this mixture was fed into the machine daily. We studied the characteristics of the refuse, the composting mixture, and the finished compost in an effort to optimize the operating parameters. We also evaluated the effectiveness of the composting process by determining the decomposition rates of the composting materials. The optimum moisture content of the composting mixture was between 30% wet basis (wb) and 40% wb in this machine. The composting machine worked well when the first reactor was filled with composting mixture and 0.5 kg lime was added once per week. The mass of the materials supplied was reduced by 84% over the study period. The decomposition rate of the volatile matter in all composting materials was 66%. The mass of the food refuse supplied was 14.8 kg/day on average, and the moisture content of the refuse was 77% wb on average. Received: October 4, 1999 / Accepted: April 4, 2000     

Separation of dissolved iron from the aqueous system with excess ligand

A new technique for the separation and pre-concentration of dissolved Fe(III) from the ligand-rich aqueous system is proposed. A solid phase extraction (SPE) system with an immobilized macrocyclic material, commonly known as molecular recognition technology (MRT) gel and available commercially, was used. Synthetic Fe(III) solution in aqueous matrices spiked with a 100-fold concentration of EDTA was used. Dissolved iron that was ‘captured’ by the MRT gel was eluted using hydrochloric acid and subsequently determined by graphite furnace atomic absorption spectrometry. The effect of different variables, such as pH, reagent concentration, flow rate and interfering ions, on the recovery of analyte was investigated. Quantitative maximum separation (∼100%) of the dissolved Fe(III) from synthetic aqueous solutions at a natural pH range was observed at a flow rate of 0.2 mL min^-1. The extraction efficiency of the MRT gel is largely unaltered by the coexisting ions commonly found in natural water. When compared with different SPE materials, the separation performance of MRT gel is also much higher.