Trophic magnification profiles of triphenyltin compounds in sub-tropical marine food webs

Abstract

Trophic magnification of triphenyltin (TPT) compounds in two marine food webs in western waters of Hong Kong (namely WI and WO) was investigated using 21 marine species. Quantification of TPT and its degradation products (mono- and di-phenyltin) in their tissues were carried out using gas chromatography equipped with mass spectrometer (GC-MS), while trophic levels of these organisms were estimated based on d15N values obtained using stable isotope ratio mass spectrometer coupled with an element analyzer (SIRMS- EA). TPT concentrations were found to increase exponentially with d15N and only in WI but not in WO, suggesting that the occurrence of trophic magnification might be site or even food web-specific. The results also confirmed the biomagnification potency of TPT in subtropical marine food webs, and have an implication on ecological risk assessment of these widely used compounds.