Due to several studies on the acute ecotoxicity of tributyltin (BT) and phenyltin (PhT), these chemicals are prohibited worldwide. It is shown that butyltin (BT) and phenyltin (PhT) are dangerous anthropogenic substances that are producing new problems in aquatic environments. TBT has long been regarded as a historical contaminant, and it was anticipated that its environmental concentration would progressively decrease over time. TBT inputs are still being recorded globally, despite attempts to reduce TBT-related pollution. This chapter monitors the dispersion of OMCs to determine whether these substances are still present in aquatic systems. BT and PhT levels worldwide are represented in the literature studies. Three case studies concerning levels of BT and PhT around the world are represented. An emphasis on the most recent case study issued in 2024 is reported.