Aquatic ecosystems are heavily affected by anthropogenic pollution, but our inability to predict toxicity of emerging pollutants to a wider range of aquatic organisms outside the standard laboratory toxicity testing hinders the potential for preventing these impacts. It has been suggested that there might be a phylogenetic signal for toxicant sensitivity. Here we have combined fish sensitivity to chemicals LC50 data for 269 fish species and 29 environmentally priority chemicals from the ECOTOX database with ecological and life history traits from other data sources like AnAge and Fishbase. From ecologic and life-history traits that we tested, maximum length, migration type, habitat salinity and the ability to airbreathe were linked with toxicant sensitivity, but only if phylogeny was not accounted for. Based on these results, we suggest that tolerance and sensitivity to toxicants can evolve as an arbitrary side effect to microevolutionary changes that allow closely related species to diverge and adapt to different ecological niches and life history strategies.