Problem of the Internal Standard Method in the Analysis of PCDDs, PCDFs in relation to Photodegradation
スポンサーリンク
概要
- 論文の詳細を見る
Photodegradation of polychlorinated dibenzo-<I>p</I>-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the analytical process was studied.<BR>Firstly, photolysis patterns of 4-8 chlorinated congeners of PCDDs/PCDFs substituted with chlorine atoms at the lateral (2, 3, 7 and 8) positions (2, 3, 7, 8-PCDDs/PCDFs) were investigated in organic solvents by irradiation with UV 365 nm (UV intensity: 3, 000μW/cm<SUP>2</SUP>) in a glass test tube with a thickness of 1.2mm. PCDFs and 2, 3, 7, 8-TeCDD were found to be decomposed to reductive dechlorinated compounds (RDC) . In PCDFs, compounds substituted with chlorine at both 1 and 9 positions were rapidly decomposed, particularly 1, 2, 3, 7, 8, 9-HxCDF being decomposed the most quickly with a half-life in toluene of 35.6 minutes. These photodegradations were also observed by irradiation with fluorescent light (UV intensity: 100μW/cm<SUP>2</SUP>) in toluene with a half-life (1, 2, 3, 7, 8, 9-HxCDF) of 11 hours.<BR>Secondly, influence of these photodegradations on the measurement by internal standard method was investigated. As a ratio of <SUP>12</SUP>C-parent compound (analysis object) to <SUP>13</SUP>C-parent compound (internal standard) differs from sample to sample, and decreased or increased amount of PCDDs/PCDFs can appear after photodegradation, their concentrations calculated by the internal standard method will be different from the original one. These views were confirmed by irradiation experiment to solutions with various concentrations of <SUP>12</SUP>C PCDDs/PCDFs.
- 日本環境化学会の論文
日本環境化学会 | 論文
- 廃棄物埋立地浸出水および処理水中の無機成分、ジオキサン、フェノール類およびフタル酸エステル類の濃度
- 有機スズ代替船底防汚剤による広島湾北部海域の底質汚染状況
- 広島湾北部における有機スズ代替船底防汚剤による海域の汚染状況について
- 難燃処理済スチレンポリマー中のポリ臭素化ジフェニルエーテルの溶媒抽出及び熱脱着 GC/MS 分析
- プレカラム分離導入システムを用いたダイオキシン類の測定