Novel strategies and approaches toward toxicity assessment: a key factor for safety assessment and management of per- and polyfluoroalkyl substances.

World Health Organization has estimated that annually 24.3％(13.7 million of 56.1 million)of all global premature deaths and 28.1％(1.57 million of 5.60 million)deaths among children under five,are linked to environmental factors[1].Unfortunately,increasing volumes of synthetic chemicals with unknown risks toward human health and ecological system have been continu-ously entering the natural environment.Per-and polyfluoroalkyl substances(PFAS)refer to compounds in which the hydrogen atoms on the carbon chain are partially or fully replaced with flu-orine atoms(Fig.1)and they constitute a group of synthetic chem-icals that are of emerging concerns to environmental chemists[2].