遊泳用プール水における過マンガン酸カリウム消費量に与える塩素酸イオン及び臭素酸イオンの影響

摘要

The concentrations of chlorate (ClO_3~- ) and bromate (BrO_3~-), generated from sodium hypo-chlorite (NaClO) used as bactericidal agents in a swimming pool collected in Yokohama, were higher than environmental quality standards for water pollution in Japan. In this study, we investigated the effect of chlorate and bromate on the potassium permanganate consumed, KMnO_4 in the swimming pool. It was found that potassium permanganate consumed decreased upon the addition of chlorate and bromate to tap and swimming-pool water, while the total organic carbon (TOC) concentration was not affected. The effect of bromate on the potassium permanganate consumed was about 18-times higher than the effect of chlorate, although the mechanism was not cleared. Our results suggested that careful attention is required concerning sanitation of a swimming pool, even though the potassium permanganate consumed as organic pollutants was low.%水中の有機汚染物の量を測定する方法（項目）には溶存rn酸素（DO），過マンガン酸カリウム（KMnO_4）消費量，化rn学的酸素要求量（COD），生物化学的酸素要求量（BOD），rn全有機炭素（TOC）量などが知られている．KMnO_4消費rn量及び硫酸酸性下における過マンガン酸カリウムCOD測rn定法（COD_(Mn)）は，還元性の無機物質〔塩化物イオン，rn鉄（II）塩，亜硝酸塩，チオ硫酸ナトリウム等〕により測rn定を正に妨害されることから，その妨害を除く試薬（硝酸rn銀，スルファミン酸等）の添加が認められてきた．