The use of anticancer drugs in chemotherapy is increasing leading to growing environmental concentrations of imatinib mesylate (IMA), cisplatinum (CDDP), etoposide (ETP), and 5-flourouracil (5-FU) in aquatic systems. Previous studies have shown that these anticancer drugs cause DNA damage in the crustacean Daphnia magna at low, environmentally relevant concentrations. To explore the mechanism of action of these compounds and the downstream effects of DNA damage on their growth and development at a sensitive life stage, we exposed D. magna neonates to low level concentrations equivalent to those that elicit DNA damage (i.e., IMA: 2000 ng/L, ETP: 300 ng/L, CDDP: 10 ng/L, 5-FU: 39 and 500 ng/L) and performed transcriptomic analysis using an RNAseq approach.