Exogenous damage causes cell DNA damage through mediated reactive oxygen levels Peiyan Guo, Ning Ma, Jingbo Shan, Techang Chen, Yujie Zhang, Sa Zhou and Wenjian Ma E3S Web Conf., 131 (2019) 01018 Published online: 19 November 2019 DOI: 10.1051/e3sconf/201913101018