[en] Highlights: • BTs sediment contamination and imposex were investigated. • Significant greater concentration of BTs was found in sediments even after the ban. • Higher TBT concentration associated with marinas and small boats • Imposex was not observed. • The results suggest presence of TBT from fresh input. - Abstract: Butyltin compounds (BTs) were used worldwide, especially because of their properties as biocides. Due to its high toxicity, the use of tributyltin (TBT) in antifouling paints has been prohibited in most countries. The occurrence and impact of BTs were assessed in surface sediments and in Stramonita rustica populations of two tropical estuaries that host major ports in northeastern Brazil. ΣBT concentrations ranged from − 1 dry weight in sediments while imposex was not observed in S. rustica. This is in contrast to previous studies that reported high incidence of imposex at the same sites. Butyltin degradation index indicates recent input of TBT at levels that might trigger imposex in gastropod species more sensitive than S. rustica. These results emphasize the need of more rigorous controls by local authorities since Brazil has restricted the use of TBT-based antifouling paints.