Neurodevelopmental disorders (NDDs), are increasingly recognized as originating from dysregulation of early
brain development, which represents a window of vulnerability to environmental compounds. Environmental
compounds may alter neurodevelopment via epigenetic mechanisms, which may not induce massive cell
death, but change the brain function through their epigenetic effect on stem cell fate and lineage development.
However, tools to systematically examine the epigenetic impact of environment on neurodevelopment are
lacking. Here we employ Microscopic Imaging of Epigenetic Landscape (MIEL) to screen ToxCast e1k
chemical library (1800 compounds) and to characterize hits that alter epigenetic landscape of human neural
precursors without inducing cytotoxicity. Recognizing environmental insults and understanding their
mechanism of action will enable the development of regulations and guidelines aimed at avoiding such insults
and the development of antidotes and protective agents when exposure is unavoidable.