Time trend of hexabromocyclododecane in the breast milk of Japanese women

Hexabromocyclododecane (HBCD) is a type of brominated flame retardant. We investigated the time trend of the stereoisomer-specific concentrations of HBCD (alpha, beta, and gamma) in breast milk samples of Japanese women by using liquid chromatography-tandem mass spectrometry (LC/MS/MS). The pooled milk lipid samples collected in 1973, 1978, 1983, 1988, 1993, 1999, and from 2000 to 2006 were analysed. The concentration was below the detection limit in the samples collected between 1973 and 1983 and increased in those collected since 1988. Between 1988 and 2006, alpha-HBCD was detected in all 11 breast milk samples collected from 25 to 29-year-old Japanese women; gamma-HBCD, in 7; and beta-HBCD, in none of the samples. Time trend of summation operatorHBCD appeared to be related to that of the industrial HBCD consumption level in Japan.     

Study of the effect of political measures on the citizen participation rate in recycling and on the environmental load reduction

Obtaining the cooperation of citizens to participate in separate waste collection is essential to create a recycling-oriented society. In this research, the degree of change in the citizen participation rate, which occurs when the contents of political measures such as the raising of awareness, provision of information, and the conditions of collection services were changed, was estimated together with the effect on the reduction in environmental load. A questionnaire survey was conducted, targeted at residents of Itabashi Ward, while logistic regression analyses were also conducted to create predictive models for recycling behavior, and sensitivity analyses of the models were carried out to estimate the increase in citizen participation rate achievable through the implementation of various political measures. It was found that the effect of "thorough perception of information" was the largest, followed by "minimization of evaluation of trouble" and "thorough perception of efficacy of measures." The effect of the improvement in the citizen participation rate on the reduction in environmental load was also evaluated quantitatively by life cycle inventory analyses. It was indicated that "maximization of perception of information" had the greatest effect. However, the reduction effect with "paper packs" and "PET bottles" was relatively small compared with that of "bottles/cans."     

Comparison of general water quality of rivers in Indonesia and Japan

In Java and Kalimantan in Indonesia, river water plays important roles in human life; for example, for transportation, and economic activities of the inhabitants. However, industrial, agricultural and domestic water is discarded into rivers directly in many developing countries, including Indonesia, since drainage systems have not been completely constructed. In this study, to evaluate the water quality and to compare those levels of environmental contaminants in developing and developed countries, water quality and contents of endocrine disrupters were measured in a total of 64 water samples (Indonesia; 28 samples and Japan; 36 samples) from 53 sites. The results indicated that, rivers in both capital cities, Jakarta and Tokyo, were contaminated. Water in rivers in Indonesia was not so heavily polluted as in Japan. Pollution in the river water in Indonesia appeared to be caused by the lack of sewerage systems. In addition, the findings on endocrine disrupters indicated that the concentration of alkylphenol in water samples was large enough to affect living organisms.     

Neurologic features of chronic minamata disease (organic mercury poisoning) and incidence of complications with aging

Abstract

To elucidate the neurologic features of chronic Minamata disease, and the incidence of complications with aging, we studied 80 patients with documented Minamata disease (organic mercury poisoning) from 1986 to 1994 (mean age: 63 years). Of the cardinal neurologic findings, sensory impairment was seen with highest frequency in 98.8% of patients limited to the extremities in 86.3%. Impairment of lower extremity coordination was observed in 60%, constriction of the visual field in 51.9%, and retrocochlear hearing loss in 41%. To assess age‐related complications, patients were separated into three groups by age: Group I (10 to 39 years); Group II (40 to 69 years); Group III (≥7 0 years). The incidences of hypertension and cerebrovascular diseases, organic ophthalmologic disorders (including cataracts), presbyacusis, and cervical spondylosis deformans increased significantly with age. Compared with a preceding survey (1981 to 1985, 171 patients, mean age: 63.5 years), the incidences of complicated hypertension and cataracts had decreased, whereas those of cerebrovascular disease and retinitis pigmentosa remained unchanged. The incidences of abnormal brain computed tomography (CT), presbyacusis, cervical spondylosis deformans, and positive tests for urine sugar also increased. The incidences of these complications other than retinitis pigmentosa were similar to those in the general population. These results accurately reflect the recent epidemiological disease tendencies in Japan toward a decreased incidence of hypertension and an increased incidence of diabetes.     

Oxidation catalyst of iron oxide suppressing dioxin formation in polyethylene combustion

A new iron oxide catalyst, which has a superior oxidation activity in carbon monoxide and polyethylene (PE) combustion, was synthesized by an aqueous solution reaction. Catalytic oxidation of carbon monoxide over six kinds of hematite obtained from the goethite was done using a microcatalytic pulse reactor, and the composition of the hematite with the highest oxidation activity was determined. With the aim of suppressing dioxin formation on combustion, incineration tests of solid wastes in PE refuse bags with and without the goethite were carried out using a commercial semibatch-type incinerator with a combustion chamber of 6.2 m³. The result confirmed that the concentration of dioxins in the flue gas decreased considerably when the refuse was incinerated in PE bags manufactured with goethite. Received: July 24, 2000 / Accepted: October 18, 2000     

Analysis of branched-chain fatty acids in humic substances as indices for compost maturity by pyrolysis–gas chromatography/mass spectrometry with tetramethylammonium hydroxide (TMAH-py–GC/MS)

Parameters that affect the degree of humification for humic substances (HSs) are deeply related to the maturity of the compost. In general, the matured composts contain HSs with a higher degree of humification. In addition, microbial activities during composting are also one of the indices for compost maturation. Branched-chain fatty acids are metabolites as the result of microbial activities in a soil environment. Such branched-chain fatty acids, regarded as humic precursors, are incorporated into HSs during the composting process. To determine whether branched-chain fatty acids in HSs can be used as biomarkers during composting processes or not, HSs were extracted from three types of composts with the different maturation, and the branched-chain fatty acids in the HSs were analyzed by pyrolysis–gas chromatography/mass spectrometry with tetramethylammonium hydroxide (TMAH-py–GC/MS). HSs with a higher degree of humification (higher aromaticity and lower molecular weight) contained higher levels of branched-chain fatty acids. These results show that branched-chain fatty acids in HSs from matured compost samples can be used as biomarkers, which indicate the history of microbial activities during overall composting process.     

Correlating pH and Swelling Degree Parameters to Understand the Sorption and Desorption Process of Diquat Herbicide from Nanocomposites Based on Polysaccharide and Clinoptilolite

Journal of Polymers and the Environment - Zeolite-based nanocomposites have become an efficient option for application in herbicide removal and controlled release systems. Our group previously...     

Evaluation of Virus Reduction by Ultrafiltration with Coagulation–Sedimentation in Water Reclamation

The evaluation of virus reduction in water reclamation processes is essential for proper assessment and management of the risk of infection by enteric viruses. Ultrafiltration (UF) with coagulation–sedimentation (CS) is potentially effective for efficient virus removal. However, its performance at removing indigenous viruses has not been evaluated. In this study, we evaluated the reduction of indigenous viruses by UF with and without CS in a pilot-scale water reclamation plant in Okinawa, Japan, by measuring the concentration of viruses using the real-time polymerase chain reaction (qPCR). Aichi virus (AiV) and pepper mild mottle virus (PMMoV) were targeted in addition to the main enteric viruses of concern for risk management, namely, norovirus (NoV) genogroups I and II (GI and GII) and rotavirus (RoV). PMMoV, which is a plant pathogenic virus and is present at high concentrations in water contaminated by human feces, has been suggested as a useful viral indicator. We also investigated the reduction of a spiked model virus (F-specific RNA bacteriophage MS2) to measure the effect of viral inactivation by both qPCR and plaque assay. Efficiencies of removal of NoV GI, NoV GII, RoV, and AiV by UF with and without CS were >0.5 to 3.7 log₁₀, although concentrations were below the detection limit in permeate water. PMMoV was the most prevalent virus in both feed and permeate water following UF, but CS pretreatment could not significantly improve its removal efficiency (mean removal efficiency: UF, 3.1 log₁₀; CS + UF, 3.4 log₁₀; t test, P > 0.05). CS increased the mean removal efficiency of spiked MS2 by only 0.3 log₁₀ by qPCR (t-test, P > 0.05), but by 2.8 log₁₀ by plaque assay (t-test, P < 0.01). This difference indicates that the virus was inactivated during CS + UF. Our results suggest that PMMoV could be used as an indicator of removal efficiency in water reclamation processes, but cultural assay is essential to understanding viral fate.     

Specific accumulation of mercury and selenium in seabirds

Total mercury (T-Hg), methyl mercury (MeHg) and selenium (Se) concentrations were determined to elucidate the relationship between Hg and Se levels in the liver of 10 seabird species. Highest concentrations of T-Hg (mean 267 microg/g dry wt), MeHg (mean 25.5 microg/g dry wt) and Se (mean 113 microg/g dry wt) were in the liver of black-footed albatross (Diomedea nigripes). An equivalent molar ratio of 1:1 between T-Hg and Se was found in the liver of individuals which contain over 100 microg Hg/g. However, such a relationship was unclear in other individuals which had relatively low Hg levels. This suggests that Se plays a role in Hg detoxification for those individuals with high Hg. In seabird tissues, Hg and Se levels should be a most important factor determining the relationship between Hg and Se, and fluctuation of Hg burden through molting and the species-specific demethylation capacity would also influence their relationships.