To estimate the risks associated with long-term human exposure to potentially mutagenic compounds, it is important to measure long-term trends in the concentrations and activity of these compounds in the environment. Samples of total suspended particulates (TSP) have been collected upon a quartz fiber filter every 6 days for the past 20 years (1980-2002) from ambient air using a high-volume air sampler placed on the rooftop of the National Institute of Public Health building in Minato, Tokyo, Japan. The mutagenicity of dichloromethane extracts of TSP samples, which divided according to season, were assayed by Ames microsuspension assay using Salmonella strains TA100 and TA98, both with and without metabolic activation system (S9 mix). Mutagenic activities (rev/m3) were calculated from the dose–response curves of the samples and from those of reference airborne particles collected by the massive sampler. Mutagenic activity increased in the first decade (1980-1990) but slowly decreased in the second decade (1990-2002). Annual average mutagenicity in TA98 was mostly higher than in TA100. Mutagenic activity was higher in autumn and winter than in spring and summer.
Indoor air quality is a significant concern, because when the hours spent sleeping, working in offices or at school are added up, people on average spend the vast majority of their time indoors where they are repeatedly exposed to indoor air pollutants. In this study, gaseous chemical compounds in institutional and residential buildings were measured in order to evaluate chemical exposure to office worker. Gaseous chemical compounds were measured in indoor and outdoor air of 18 institutional buildings and 77 residential houses throughout Yokohama in winter and summer. Four kinds of diffusive samplers were used in this study: DSD-BPE/DNPH packed with 2,4-dinitrophenylhydrazine and trans-1,2-bis (2-pyridyl) ethylene coated silica for ozone and carbonyls; VOC-SD packed with Carboxen 564 particles for volatile organic compounds; DSD-TEA packed with triethanolamine impregnated silica for acid gases; and DSD-NH3 packed with phosphoric acid impregnated silica for basic gases. As results of this study, there were no institutional buildings exceeding Ministry of Health, Labour and Welfare, Japan (MHLW) guidelines in winter and summer. However, in residential houses, 19% houses in summer and 15% houses in winter exceeded guidelines by MHLW. Total gaseous chemical compounds of institutional buildings is about half of residential houses in both summer and winter. Almost all compounds in residential indoor air were present at higher levels in summer than in winter. However, the nitrogen dioxide concentrations in residential indoor air particularly increased only during winter and was well correlated with the formic acid concentration (correlation coefficient=0.958).
A highly sensitive analytical method was developed for the determination of para-cumylphenol (PCP) and bisphenol A (BPA) by tandem liquid chromatography-mass spectrometry and was applied to the measurement of environmental water. The method detection limits of PCP and BPA for seawater were 2.2 ng/L and 1.9 ng/L, respectively, and the corresponding values for river water were 5.2 ng/L and 5.0 ng/L. Various water samples in Nagoya citywere found to containPCPand BPA at concentrations ranging from less than 5.2 to 160 ng/L and 33 to 290 ng/L, respectively.
An aerial application of neonicotinoid insecticide, thiacloprid, by a manned helicopter for controlling insect (Monochamus altermatus Hope) damage was carried out on pinewoods of Chikuma-city in Nagano Prefecture in June 2013. An investigation on thiacloprid drifts was conducted because many people reside near the applied area. Drifts in the air and in fallouts were collected at 4 locations near the applied area for three days after aerial spraying; and thiacloprid was quantified by liquid chromatography/tandem mass spectrometry. The result is that thiacloprid in the air was found from 4 locations at the maximum concentration of 1.9 ng/m3 per day. Thiacloprid in fallouts was quantitatively detected from 3 locations at the maximum amount of 7900 ng/m2 over three days. The maximum drift ratio was calculated to be 0.066 %. The results confirmed that a low-level drift occurred after the aerial application by a manned helicopter. The results suggest that the combination of air concentration measurements and fallout monitoring improved the evaluation of residential exposure to neonicotinoid insecticide.
In order to grasp the change of metal (Al, Fe, Mn, Zn, As, Pb and Cu） concentrations in agricultural water through paddy field, total metal and dissolved metal concentrations in influent, paddy surface water and effluent were measured. There were few differences between Total Al and Total Fe concentrations in influent and effluent. Total Zn, Total Pb and Total Cu concentrations in effluent were lower values than influent. Zn, Pb and Cu may settle or adsorb to the soil in paddy field. Total As concentration in effluent was higher values than influent. The main factor may be the elution of As from manures and paddy soil and methylation of As. Dissolved Mn concentration for Total Mn in effluent was higher value than influent. The main factor may be the elution of Mn from paddy soil and dissolution of organic complexes of Mn.
Wastewaters containing more than several % of total organic carbons from chemical laboratories should be rejected in the process of wastewater treatment system composed of flocculation- sedimentation procedure in order to avoid technical troubles. Measurement system by supercritical water oxidation method was applied successfully to determine total organic carbons in chemical wastewaters containing various kinds of heavy-metallic compounds.