Matrix effect is one of the major problems in quantitative analysis of organic compounds in environmental sample. The aim of this study was to determine the matrix effect in the analysis of 42 pesticides in river water by liquid chromatography-tandem mass spectrometry (LC/MS/MS) with two kinds of approaches. One approach was a conventional way to compare pesticide responses between the pesticide-spiked solution of river water sample and the pesticide standard solution. The other was using a chromatographic profile of a pesticides constantly added to a postcolumn eluate of river sample (PCI method). The matrix-effects were varied among the pesticides. Almost no ion suppression was observed for the ions of metalaxyl, cafenstrole and isoxathion. On the other hand, the ionization efficiencies of some other pesticides added by PCI were varied with the retention times of river water components. Ion suppression in the analysis of the pesticides was examined with river water samples collected at 7 of sampling sites. Because the matrix components were varied among the sites, it is difficult to prepare a "matrix-matched standard" which eliminates the matrix-effects. A method for diluting sample solution was examined to reduce the ion suppression. The suppression between 30 and 50% could be reduced to below 10% by 5-fold dilution of water sample, and for the suppression above 50%, the sample dilution was not effective to reduce the suppression. A sample clean-up method with solid phase extraction (SPE) was examined in two different pHs to reduce the matrix-effects. The ion suppression in water sample of non-adjusted pH (pH around 9) was smaller than that in the sample adjusted pH3. Then, in the case of measuring non-acidic pesticides, better results can be expected with smaller matrices from water sample of non-adjusted pH.

Recently, passive air sampling in indoor air monitoring of volatile organic compounds (VOCs) has received increasing attention, because it is easy to handling and low cost sampling method. However, in order to calculate concentration of each target VOCs, information of sampling rate (SR) is needed. Therefore, one of the aims of this study is to establish the method convenient to obtain SR by exposure test which adopt a small and cost-effective exposure chamber. The result show that this approach was effective, because the sampling rate obtained are comparable with reference value and are reproducible result. Another aim is evaluations of effect of adsorbent and sampler case of passive air sampler to SR. The six passive air samplers consist two kinds of passive air sampler cases and three kinds of absorbents were exposed to VOCs for 24 hours and SR are determined. The results showed that sampler case and adsorbent affect the value of SR.

In this study, we proposed the rapid and simple analytical method for mancozeb (Product name : Jimandaisen) in agricultural products. The analysis of mancozeb is known to be difficult in a simultaneous quantification as well as requires complicated operation in a separated quantification method.
We used two types of methods which are the wiping method, and the wiping and filteration method with FT-IR (ATR or transmission) according to conditions of measurement. With these method, measurement and quantification of mancozeb can be completed within one hour.
Especially, the limit of detection (LOD) of the wiping and filteration method which is capable of quantification with the entire sample was 10 times less than the regulatory value. It showed that this method can be used to determine whether to exceed of regulatory value or not. Furthermore, this method is not affected by other pesticides in quantification. The results showed that this rapid on site measurement method can contribute to the safety and security for agricultural products through inspection of products before the distribution of the market.