Occurrence of hydroxylated polychlorinated biphenyls in the brain of cetaceans stranded along the Japanese coast

Organohalogen contaminants and metabolites in cerebrospinal fluid and cerebellum gray matter in short-beaked common dolphins and Atlantic white-sided dolphins from the western North Atlantic

“…3). In Kunisue et al (2007), the ΣOH-PCB/ΣPCB ratio for cerebrum in melon-headed whales, striped dolphins, and finless porpoises were approximately three orders of magnitude lower than the ratios in CSF and approximately one order of magnitude lower than the ratios in cerebellum GM in dolphins from our study (Fig. 3).…”

“…In that effort, Takasuga et al (2004) showed that the levels of OH-PCBs in human CSF were higher than those of PCBs, an opposite pattern to what was observed in serum. In the only other study on OH-PCB residue levels in cetacean brains, Kunisue et al (2007) reported concentrations of ΣOH-PCBs in the cerebrum of melon-headed whales, striped dolphins, and finless porpoises that ranged from 0.020 to 0.290, 0.020 to 0.330, and 0.170 to 0.240 ng/g wet wt,…”

“…To the best of our knowledge, there has been no systematic assessment of OHCs in specific brain structures. With respect to OH-PCB accumulation in the brain, only one study has reported OH-PCBs in the cerebrum of marine mammals (Kunisue et al, 2007). Furthermore, there have been no studies on the analysis of PBDEs and OH-PBDEs in the brains of any cetacean or pinniped species.…”

Simultaneous detection of multiple hydroxylated polychlorinated biphenyls from a complex tissue matrix using gas chromatography/isotope dilution mass spectrometry

“…Among the tri-to hepta-chlorinated OH-PCB congeners, some unknown species were detected in the liver of Baikal seals. It has been already reported that some unknown OH-PCB congeners were discovered in wildlife blood, liver, and brain [15,17,24]. Since these unknown species are likely metabolic products of PCBs and seem to help in the elucidation of the transport kinetics of OH-PCBs, their identification is of primary importance.…”

“…These studies suggested that the levels and profiles of OH-PCBs in animal blood vary by species and that several animals may be at a risk from these metabolites including congeners which are not found in human are present. However, because of difficulties in detecting low-chlorinated (e.g., 3-4 chlorine atoms) OH-PCBs in biological tissues, comprehensive investigations on the levels of various OH-PCB homologs in the brain and liver are still limited [23,24], In fact, because tri-and tetrachlorinated OH-PCBs are unstable and characterized by low recovery rates, conventional pretreatment procedures (e.g., sulfuric acid treatment or multilayer silica-gel column) [15,23,24] cannot be used for their analysis. Thus, to analyze lower-chlorinated OH-PCBs, mild pretreatment methods before derivatization are required.…”