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• Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans • Negative correlations were found between length and TEQ values in franciscanas.• PCB concentrations found are among the highest ever reported for cetaceans. a b s t r a c t a r t i c l e i n f o Blubber samples from three delphinid species (false killer whale, Guiana and rough-toothed dolphin), as well as liver samples from franciscana dolphins were analyzed for dioxins and related compounds (DRCs). Samples were collected from 35 cetaceans stranded or incidentally captured in a highly industrialized and urbanized area (Southeast and Southern Brazilian regions). Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans. Non-ortho coplanar PCBs, for franciscanas (82%), and mono-ortho PCBs (up to 80%), for delphinids, constituted the groups of highest contribution to total TEQ. Regarding franciscana dolphins, significant negative correlations were found between total length (TL) and three variables, ΣTEQ-DRCs, ΣTEQ-PCDF and ΣTEQ non-ortho PCB. An increasing efficiency of the detoxifying activity with the growth of the animal may be a plausible explanation for these findings. This hypothesis is reinforced by the significant negative correlation found between TL and PCB126/PCB169 concentration ratio. DRC concentrations (ng/g lipids) varied from 36 to 3006, for franciscana dolphins, as well as from 356 to 30,776, for delphinids. The sum of dioxin-like and indicator PCBs varied from 34,662 to 279,407 ng/g lipids, for Guiana dolphins from Rio de Janeiro state, which are among the highest PCB concentrations ever reported for cetaceans. The high concentrations found in our study raise concern not only on the conservation of Brazilian coastal cetaceans, but also on the possibility of human health problem due to consumption of fish from Brazilian estuaries.

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The present article describes the development of an analytical method for the determination of 13 perfluorinated alkyl substances (PFAS), as well as its application to real sewage sludge samples to confirm the presence of these compounds. The isolation of the analytes was performed by agitation, sonication and centrifugation techniques, followed by EnviCarb cleanup and weak anion exchange solid-phase extraction. Sensitive and selective determination was carried out by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Six mass-labelled internal standards were used to ensure the accuracy of the analytical results following isotopic dilution method. Several mobile phases (acetonitrile, methanol, mixtures of both and water with ammonium acetate or acetic acid) have been tested to reach the best resolution and reproducibility results. Other parameters related to MS/MS conditions were optimized. The reliability of the method was confirmed by the evaluation of linearity (R(2) = 0.995-0.999), accuracy (84-99%) and injection repeatability and reproducibility (relative standard deviation below 19 and 23%, respectively). Limits of detection ranged from 0.007 to 2.217 pg. Recoveries show values higher than 80% for most of the target compounds. The application of this method to twenty real samples demonstrates its efficiency and accuracy, as well as provides for the first time to our knowledge, PFAS levels in sewage sludges from Spain.

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Concentrations of Dechlorane (Dec) 603 (0.75 ng/g lipid weight (lw); mean) and Dec 602 (0.38 ng/g lw; mean) were quantified in more than 95% of the franciscana (Pontoporia blainvillei) dolphin samples, whereas the frequency of detection decreased to 75% for Dechlorane Plus (DP) (1.53 ng/g lw, mean). The presence of Chlordene Plus (CP) was also observed (0.13 ng/g lw, mean) in half of the samples. On the contrary, Dec 604, decachloropentacyclooctadecadiene (aCl(10)DP), and undecachloropentacyclooctadecadiene (aCl(11)DP) concentrations were below the limit of quantifications in all cases. To the best of our knowledge, this is the first article reporting the presence of Dec 603, Dec 602, and CP in mammals. For comparative purposes, levels of Mirex, polybrominated diphenyl ethers (PBDEs), and decabromodiphenylethane (DBDPE) are also reported. Considering geographic distribution evaluation together with the strong positive correlations found between DP and PBDEs (r(s) = 0.63; p < 0.01), highly anthropogenic areas were identified as potential sources of these chemicals in this dolphin species. However, local sources for Dec 602, 603, Mirex, CP, and DBDPE were not found indicating that in this case historical use and/or atmospheric transport and deposition may play an important role in their fate.