Toxicity assay is crucial in identifying biological mechanisms, detecting disease and screening therapeutics. Single cell toxicity assay reveals heterogeneous responses of each cell without ensemble average, but still cannot indicate responses of the same individual cells to multiple treatments. This article reports an identical cell assay that can be used at high throughput to locate each cell and track its responses to multiple treatments (chemicals and radiation), thus greatly facilitates toxicity based drug screening and testing. Each cell is located through its coordinators pre-engraved on a patterned substrate with soft lithography. Cell responses to X-ray radiation, chemical reagents or a combination of both are obtained by probing reactive oxygen species (ROS) signals and quantified by fluorescent intensity in MATLAB. The method can provide toxicities of over thousands of identical cells with superior statistics power to allow deep analysis of toxicity data.