Water contamination has come to the forefront of global debate as a result of high profile cases such as those in Flint, Michigan, USA, or the pollution of the Ganges River in India. Koji Kosaka of the National Institute of Public Health in Japan, has investigated the contamination of the Yodo River Basin in Japan, with the precursors of the carcinogen N-Nitrosodimethylamine (NDMA). He recently spoke with The Column about his use of high performance liquid chromatography (HPLC) to uncover the source of contamination and the chemical precursors responsible.

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