To compare the sensitivity and exposure of marine and estuarine species (further noted as saltwater) to pesticides to those of freshwater species we searched the peer reviewed literature. Relevant literature references were assembled in two EndNote libraries, one on saltwater species, and one on freshwater species, comprising a total of 3627 references. Based on an extensive toxicity database and the EndNote libraries we developed Species Sensitivity Distributions (SSDs) to assess differences in sensitivity. Furthermore we compared the toxicity (L(E)C50) of all pesticides for which more than two species were tested both for salt and freshwater. To assess differences in exposure we compared literature on pesticide level and persistence.The results on sensitivity indicated that there is no systematic difference in sensitivity to pesticides between fresh and saltwater species. For some pesticides either saltwater or freshwater organisms may be more sensitive. We found such an effect for trifluralin (saltwater species more sensitive) and parathion and HEOD (freshwater species more sensitive). Also, comparison within taxonomic groups showed no systematic difference of saltwater compared to freshwater species. When comparing all available species data within taxonomic groups, some saltwater groups showed higher sensitivity to specific pesticides compared to their freshwater representatives, e.g. saltwater molluscs were more sensitive to methoxychlor compared to freshwater molluscs. Whereas, freshwater arthropoda were more sensitive than saltwater anthropoda for copper sulphate and parathion.The results on exposure show that pesticides tend to have higher levels in surface water of freshwater compared to the saltwater environments. Such inference could not be made for sediments since the amount of available data was limited. However, based on general insights in persistence and absorption capacity there seems to be a strong indication that very persistent pesticides with a very high absorption capacity (e.g. DDT) tend to accumulate in saltwater sediments.