Insecticide pyrethroids in liver of striped dolphin from the Mediterranean Sea

Pyrethroid pesticides were analysed in liver of striped dolphin (Stenella coeruleoalba) from the Alboran Sea (south of Spain, Mediterranean Sea). The occurrence and bioaccumulation of pyrethroid insecticides in marine mammal tissues from the northern hemisphere had never been determined before. Pyrethroids were detected in 87% of the specimens with a mean total concentration of 300 ng g lw ± 932 (range 2.7–5200 ng g lw). Permethrin and tetramethrin were the main contributors to the pyrethroid profiles, with enantiospecific accumulation for the first and isomer specific accumulation for the latter. Bioaccumulation of pyrethroids was unlike that of persistent organic pollutants (POPs), as pyrethroid concentrations were not correlated to the maturity stage of the specimens. Concentrations slightly increased from calves to juveniles, whereas juveniles presented similar concentrations to adults. Metabolization of pyrethroids after achieving sexual maturity might account for this pattern.

This work has been financially supported by the Generalitat de Catalunya (Consolidated Research Groups 2014 SGR 418 – Water and Soil Quality Unit), Loro Parque Foundation (Project Flame), CEPSA and EcoCet Project (CGL2011-25543, National Research Plan by the Ministry of Economy and Competitiveness). R. de Stephanis and J. Giménez were supported by the Spanish Ministry of Economy and Competitiveness, through the Severo Ochoa Programme for Centres of Excellence in R+D+I (SEV-2012-0262) and R. de Stephanis by the Subprograma Juan de la Cierva. Thanks are due to the Consejería de Agricultura, Pesca y Medio Ambiente and the Agencia de Medio Ambiente y Agua of the Junta de Andalucía, specially to María Soledad Vivas, Carolina Fernández and Eduardo Fernández, to Centro de Recuperación de Especies Marinas Amenazadas (CREMA), specially to Juan José Castillo, and to all the people who helped in the sample collection.