title: HCB, p,p'-DDE and PCB ontogenetic transfer and magnification in bluefin tuna (Thunnus thynnus) from the Mediterranean Sea.
abstract: The bluefin tuna, Thunnus thynnus (Linnaeus 1758), is biologically and economically important in the Atlantic--Mediterranean ecosystems. Bluefin tuna feed on diverse food items depending on their age, thus they occupy different trophic levels during their lifespan. Hexachlorobenzene (HCB), p,p'-DDE and polychlorinated biphenyls (PCBs) are well-known persistent organic pollutants (POPs) in the Mediterranean basin. The relationship between stable isotopes of nitrogen (N) and the POP residue levels in tissues has recently increased knowledge on the link between the trophic levels and the contaminant accumulation. Trophic levels were estimated by using 15N/14N ratio (delta15N) and HCB, p,p'-DDE, and forty-three PCBs were quantified in bluefin tuna from the southern Tyrrhenian Sea. Results showed that changes in PCB and p,p'-DDE concentrations were a function of size and trophic level, while no correlations were observed for HCB. Apart from HCB and PCB nos. 101, 207, 95, 158, and 60 + 56, which did not show any significant increase per trophic level, the other PCBs and the p,p'-DDE increased significantly. The ontogenetic magnification factor of PCBs was 6.6 +/- 0.5, which was significantly (12 times) higher (p < 0.05) than the values found for p,p'-DDE (1.4) and HCB (1.4).
authors.affiliation: G. Sarfatti Department of Environmental Sciences, University of Siena, via P.A. Mattioli, 4, I-53100 Siena, Italy. corsolini@unisi.it
authors.forename: Simonetta
authors.initials: S
authors.lastname: Corsolini
authors.forename: Gianluca
authors.initials: G
authors.lastname: Sarà
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Borghesi
authors.forename: Silvano
authors.initials: S
authors.lastname: Focardi
mesh_terms: D000818:Animals; D049628:Body Size; D003633:Dichlorodiphenyl Dichloroethylene / Q000378:metabolism*; D004784:Environmental Monitoring; D020387:Food Chain; D006581:Hexachlorobenzene / Q000378:metabolism*; D008522:Mediterranean Sea; D009587:Nitrogen Isotopes; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D012623:Seawater / Q000737:chemistry*; D014413:Tuna / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D009587:Nitrogen Isotopes; D014874:Water Pollutants, Chemical; D003633:Dichlorodiphenyl Dichloroethylene; D006581:Hexachlorobenzene; D011078:Polychlorinated Biphenyls