Butyltin compounds in sediment and biota from the lagoon of Bizerte (northern Tunisia): Potential risk for consumers?

ABSTRACT

Levels of butyltins (BTs) were monitored in sediment samples and in seven fish species (Boops boops, Diplodus sargus, Sarpa salpa, Serranus scriba, Spicara smaris, Trachurus draco, and Trachinus mediterraneus), five bivalve species (Cerastoderma glaucum, Chlamys flexuosa, Mytilus galloprovincialis, Pinna nobilis, and Ruditapes decussatus), two gastropod species (Bolinus brandaris and Hexaplex trunculus), cuttlefish (Sepia officinalis), and shrimp (Penaeus notialis), most of which are commonly consumed in Tunisia. Samples were collected from Bizerte lagoon during March 2012. Average concentrations of total BTs found in sediment and the muscle of fishes, bivalves, gastropods, cuttlefish, and shrimp were 17.7, 11.5, 31.8, 36.9, 8.1, and 9.4 ng Sn g⁻¹ dw, respectively. The calculation of tolerable average residue levels and non-cancer hazard quotient for tributyltin (TBT) showed that daily exposure of these seafood to TBT is unlikely to cause any deleterious effects to humans, thus indicating that consumers may not be at risk through the inclusion of these species in their regular diet.

KEYWORDS:

• butyltins
• seafood
• tolerable average residue levels
• non-cancer hazard quotient
• Bizerte lagoon
• Tunisia

Acknowledgments

The present study results from a collaboration between the Faculty of Sciences of Bizerte (Tunisia) and the Faculty of Chemistry (Oviedo, Spain). The authors are grateful to the staff of the Department of Physical and Analytical Chemistry (Oviedo) for their help in butyltins analyses. Finally, we acknowledge the editor and three anonymous referees for valuable comments and suggestions that greatly improved the article.