On April 11, more than thirty members, colleagues and friends of the Laurentian SETAC community populated the cozy upstairs room of Rayhoon’s Persian Eatery, for a very interesting presentation by Shane de Solla (Wildlife and Landscape Directorate, Environment Canada) on the detection of perfluorinated compounds (PFCs) in snapping turtles near Hamilton International Airport.
This project, started in 2010, originally planned to investigate spatial trends in PFCs in southern Ontario by examining a municipal (Toronto), an industrial (Hamilton) and a rural (Binbrook) site, using the snapping turtle as an indicator species, as they are long-lived and sedentary, and it is possible to sample blood from these species using minimally invasive sampling techniques, without requiring sacrifice of the animal. However, unexpected detection of plasma concentrations of PFCs ten times higher at the rural reference site, forced the investigators to review their hypotheses. A closer examination of the various types of PFCs found at each site using multivariate analysis revealed differences in the classes of compounds found at each location. While the Toronto site was dominated by perfluorotridecanoate and perfluorononanoate, the Hamilton site mainly consisted of perfluorodecanoate, and the Binbrook site had high concentrations of perfluorooctanesulfonate (PFOS) and perfluorohexanesulfonate. Upon reviewing the hydrology of the Welland river watershed in more detail, it was discovered that spring drainage from the southern part of Hamilton Airport (where, incidentally, firefighting training exercises took place) was likely the source of PFCs into the Welland River watershed. Further sampling then took place in various streams within the Welland River watershed in the spring of 2011, which included water, invertebrate, small fish and turtle plasma samples. These data confirmed the presence of PFCs at higher concentrations downstream of the airport in comparison with (new!) reference sites, with concentrations generally decreasing with distance. The highest concentrations were detected in the plasma of snapping turtles. Shane also showed that concentrations of perfluoroethylcyclohexane sulfonate, a cyclic PFC used in aircraft hydraulic fluid, decreased with distance from the airport, thus leading further strength to the hypothesis that the source of contamination was the southwest corner of the Hamilton Airport. Although
fish consumption guidelines for PFOS did not exist at the time (because there was no need for them), in part due to the levels of PFOS found in fish in this study, preliminary guidelines were developed and released in 2011 by the Ontario Ministry of the Environment, with initial restrictions on fish consumption guidelines at 0.08 ug/g, and complete fish consumption restrictions at 0.16 and 0.64 ug/g (for sensitive and general populations, respectively). Shane gave a lively presentation, which was followed by a dynamic question/discussion period. With a change of pace from our usual pub nights, the food arrived as the question period ended. Hence, the attendees had the opportunity to catch-up and network over a delicious Persian meal. Submitted by Ève Gilroy (with comments from Natalie Feisthauer)
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