Vol.5 No.4 2013
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Research paper : Standardization of environmental analysis methods of hazardous chemicals (S. Taniyasu et al.)−272−Synthesiology - English edition Vol.5 No.4 (2013) 24293 developed and standardized in this research was a method that, for the first time, separated and measured NP into 13 types of isomers with varying degrees of endocrine disrupting effect. This is equivalent to the individual measurement and selection of 17 highly hazardous isomers with different hazardous levels among the 210 isomers of dioxins (collective name for polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran). Since the NP isomers showed different estrogen-like activities, it was necessary to understand the concentrations of each isomer in the environment for accurate risk assessment, and the accumulation of the concentration data for each isomer in the environmental samples was necessary.To standardize the developed analysis method as ISO, it was necessary to make adjustments with Germany, who was acting as the convener and was working on the total measurement method for NP (ISO 18857-1[9]) in ISO/TC147/SC2/WG17 (Phenols). Therefore, a meeting was set up for a preliminary discussion with the chairman of ISO/TC147 (Germany) and the convener for WG17 (Germany). We explained the necessity for the detailed analysis of individual isomers that enabled accurate assessment of hazards in the environment. The significance of such analysis was shared, and the new proposal by Japan on the analysis for individual isomers was approved at the ISO/TC147 meeting in 2003. As a result, the new analysis method was selected as the ISO New Work Item Proposal (NWIP) in 2005 before starting the JIS standardization,[3] and international standardization was started by the the working group for phenols (WG17). In the ISO proposal, the analysis method proposed by Japan was generally accepted in the process of discussion with the TC members, but there were several arguments about the reference material and the suspended solids (SS) in the environmental water samples. The focus was placed on the effect of analysis precision due to the amount of SS in the environmental water sample. Hence, agreement was made to conduct the quality control studies using the environmental water samples with different amounts of SS and adding this result in the Annex (Informative). For the reference material, it was necessary for the measurers themselves to evaluate the commercially available mixtures. Therefore, measurements for the mixture of commercially available materials from the five manufacturers were listed in the Annex (Informative). The details will be described in subchapters 3.1 and 4.1. After the above discussion, the working draft (WD) was submitted in 2005, followed by the committee draft (CD) in 2006, the draft international standard (DIS) in 2009, and the final draft international standard (FDIS) in 2009. Finally, the ISO 24293 was issued as the international standard in July 2009.2.2 Necessity and standardization of the environmental analysis technology for PFOS/PFOAPFOS and PFOA are types of perfluoroalkyl substances (PFASs) that have fluoroalkyl groups as shown in Fig. 2. Because PFOS/PFOA-related substances have extremely strong carbon-fluoride covalent bond, in addition to both hydrophobic groups (fluoroalkyl groups) and hydrophilic groups (sulfonate groups or carboxyl groups), they have excellent, diverse physical and chemical properties, such as chemical and thermal inertness, low surface energy and special surface active properties. Therefore, they have been used widely as functional industrial materials of fluororesin, state-of-the-art electronic device, semiconductors, coating, etching, photograph, emulsifiers, water repellents, soil release agents, firefighting foams, and their intermediary materials. Figure 3 shows the social and research trends of the PFOS/PFOA-related substances. The manufacturing method of the PFOS/PFOA-related substances was developed in the 1940s, and they became commercially available in the 1950s. However, PFOS was detected in high concentration in wild animals in February 2000, and the 3M Company of the United States announced the phase-out of the production of related materials in May 2000. Hence, the environmental issues due to PFOS-related substances have became widely studied and known. Thereafter, their environmental persistence, high accumulation in organisms, and concerns of the effects on humans and organisms became apparent, and they were even detected in high concentration from wild animals in the polar region.[10] In such situations, international regulations on their use and treatment of their waste were considered, and PFOS and PFOA became “Type II Monitoring Chemical Substances” under the Act on the Evaluation of Chemical Substances and Regulation of Their Manufacture, etc. of Japan (CSCL) in December 2002. In January 2006, the US Environment Protection Agency (EPA) requested the major manufacturers voluntary reduction and elimination of PFOA and PFOA precursors by year 2015, and efforts on waste reduction started by setting up guidelines for drinking water around the water treatment plant. The considerations for regulations by the POPs Convention were started in June 2005 for PFOS. In 2010, PFOS and perfluorooctane sulfonylfluoride (PFOSF) that is its raw material became the substances subject to the POPs Convention, and were designated “Type I Monitoring Chemical Substances” under the CSCL in Japan. Their production and use were banned worldwide except for certain essential use. However, measures would be delayed if the analysis method were standardized after the regulations. To execute measures efficiently in industry and society, it is necessary to ensure the appropriate risk profile by establishing a reliable analysis method before the danger of a new chemical substance becomes widely known in society. Figure 4 shows the scenario of the standardization of the PFOS/PFOA analysis method. The procedures taken in the standardization will be described below.The Potential Pollutants Group, Research Institute for Environmental Management Technology, AIST, conducts basic researches on various potential pollutants based on the

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