“…Colorimetric assays can be used to quantify the activity of hydrolases, oxidases, and other enzymes in homogenates of exposed planarians during neurodevelopment or in adulthood. The activity of oxidative stress related enzymes, such as catalase and superoxide dismutase, has been a popular molecular biomarker of toxicity in planarians (Zhang, Zhang, Yi, and Zhao, 2014, 2018). Additionally, the activity of neuronal enzymes, such as acetylcholinesterase (AChE), an important toxicological target (Russom, LaLone, Villeneuve, and Ankley, 2014), have been quantified (Hagstrom et al., 2018; Ireland, Zhang, et al., 2022; Li, 2008).…”