Vol.5 No.4 2013
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Research paper : Standardization of environmental analysis methods of hazardous chemicals (S. Taniyasu et al.)−275−Synthesiology - English edition Vol.5 No.4 (2013) standardization (in effect from March 22, 2011[4]) was done to meet the international compliance according to the principle of domestic standardization (WTO/TBT Agreement) based on the international standard, and in response to the demands from the Japanese analysis laboratories for the establishment of the Japanese standard to ensure quality control and collaborative systems in Japan. The JIS standard is the addition, removal, and modification of the rules (MOD) based on the ISO standard. The modified points of the ISO standard include: not to use the LC-MS (written in Annex (Informative) of ISO 25101), addition of filtering procedures of samples that can be applied to SS rich water such as wastewater in JIS Appendix (Informative), and the addition of possible measurements of related substances other than PFOS and PFOA in JIS Appendix (Informative). For these modifications, quality control studies were conducted twice to check the adequacy of the new analysis method.2.3 Timing of the standardizationThe common points of ISO 24293 and ISO 25101 are that they started from scientific research on the environmental behavior, internationally acclaimed results published after developing a new analysis method, and the international standardization started at the stage when de facto standard was established as a consensus among the research community. This is in opposition to the conventional flow where the domestic standardization was done after the economic and social demands manifest and then fine adjustments are made with the international standard. In other words, the public sector decided that an environmental analysis method from a global viewpoint was necessary for the appropriate international use of chemical substances and for the global environmental protection. Furthermore, to ensure that the international chemical substance regulation could be done effectively, the awareness was raised among the research community by releasing the research results as soon as possible, and efforts were made to obtain a highly reliable analysis method by providing the international standard at the same time as the enforcement of the standard. The research was conducted with the point of view that “reliable analysis value and standard analysis technologies that ensure reliability are essential in the control of hazardous chemical substances.”3 Development of the analysis method3.1 Development of the analysis method for nonylphenol The total analysis method for NP already existed in 2002 as JIS K 0450-20-10, and the analysis of general water samples could be done.[5][9] However, other than the linear 4-NP shown in Fig. 1, there were theoretically 211 isomers of NP by different side chains and substitution sites,[17] and dozens of isomers were detected with different environmental degradability and hazardousness from the environmental samples.[18][19] Therefore, it was necessary to develop a method to accurately quantify each isomer in order to conduct a highly reliable risk assessment. Using the gas chromatograph/preparative fraction collector (GC-PFC)Term 1 that was uncommonly used in Japan at that time, the NP isomers in the mixture were separated and refined. Individual isomers were collected in the glass tube cooled by liquid nitrogen, and this procedure was repeated about 100 times until six fractions were obtained for the amount necessary for a hormone activity test. It was confirmed that the endocrine disrupting activity differed greatly for different individual isomers.[6][7][18] Next, the various commercially available capillary columns were compared to establish the optimal analysis condition for the advanced separation of the NP isomers. The method for maximum separation analysis of NP in the complex mixture was investigated using the two-dimensional gas chromatographTerm 2 mass spectrometry (GC×GC-MS), and we succeeded in separating 102 components in an NP product.[20]While it was possible to separate NP into multiple components if such state-of-the-art analysis technology was used, from the perspective of quality control, it was necessary to have a standard where the majority of the users could obtain the same data. Therefore, for the analysis of individual NP isomers in the ISO standard, 13 NP isomers that could be separated by general GC were set as the subjects of analysis. The styrene-divinylbenzene solid phase extraction method was used as the extraction method, since it could be used universally for water analysis. Since NP was used as the raw material of nonylphenol ethoxylate, which is a nonionic surfactant that can be detected from almost all water environments, utmost care was needed for contamination control. There were possibilities that NP might be present in the silica gel column cartridge and the anti-clogging agent (glass beads) in the solid phase extraction.The selective ion monitoring (SIM) method of the gas chromatograph mass spectrometer (GC-MS) was used, and quantification was done using ions with good sensitivity and separability for each isomer (Fig. 5). Normally, five to six peaks were detected at m/z 135 (m/z is mass-to-charge ratio, or the value obtained by dividing the charge z with mass m), but in this analysis method, the assessment for individual isomers became possible by selecting an optimal monitor ion for each of the 13 isomers, and then calculating the relative response factor (RRF) of each NP isomer and the internal standard Term 3. For the investigation of the ion selection for the NP isomer, refer to Horii et al. (2004).[21] The reasons for the complicated quantification of individual NP isomers are because NP is a complex mixture, the commercially available standards for their isomers are limited, and the fragmentation patternsTerm 4 differ greatly by isomers. In the situation at that time where the standards for individual isomers were not available, the only way was to use the NP mixture as a standard for quantification, and it was necessary

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