Data comprise results of laboratory experiments assessing the impacts of beta radiation (phosphorus-32) on reproduction, development and DNA damage in a marine and freshwater crustacean species. All crustacean samples were collected either from Lock Lake, Portsmouth (marine crustacean Echinogammarus marinus) or from the River Ems, Emsworth (freshwater crustacean, Gammarus pulex). Laboratory experiments were conducted periodically from summer 2015 to autumn 2016 at the University of Portsmouth. The data are of use in elucidating the mechanisms and effects of low-dose ionising radiation on an important group of model organisms in radioecology. Full details about this dataset can be found at https://doi.org/10.5285/b70afb8f-0a2b-40e6-aecc-ce484256bbfb
