Publication year: 2003-04-02

Publication title: Polybrominated diphenyl ethers (PBDEs) in grey seals during their first year of life—are they thyroid hormone endocrine disrupters? Environmental Pollution, 126

Publication authors: Hall, A.J., Kalantzi, O.I. & Thomas, G.O.

Publication editors: Sea Mammal Research Unit (SMRU)

Publication year: 2009-07-14

Publication title: Exposure to persistent organic pollutants and first-year survival probability in gray seal pups. Environmental Science and Technology, 43.

Publication authors: Hall, A.J., Thomas, G.O. & McConnell, B.J.

Publication editors: Sea Mammal Research Unit (SMRU)

Blubber samples were collected from grey seal ( Halichoerus grypus ) pups on the Isle of May (Firth of Forth, east Scotland). Sixty suckling pups were selected at random from the island's population, weighed, measured and tagged. Five of these tags malfunctioned but two of the affected pups were still included in the study, leading to a total of 57 pups in the final dataset. The pups were recaptured repeatedly before and after weaning, with weight, length and axillary girth being re-measured each time. These measurements were used to estimate blubber reserves based on mass/length, as detailed in Hall et al. (2009), and linear regression was used to derive estimates of pup mass at weaning. All animal capture was undertaken during the breeding season while the pups were still on land. Blubber biopsy samples were collected from the pups when they were first recaptured after weaning. Samples were stored at -20°C, then extracted using the Soxhlet method. Lipid content was determined gravimetrically while Gas Chromatography-Mass Spectrometry (GC-MS) was used to determine wet weight concentrations of contaminants per lipid proportion of the sample. A linear back calculation based on the known rate of contaminant concentration in blubber post-weaning was used to correct values to the concentration at weaning. Methods and analyses are detailed in Hall et al. (2009) and references therein. The data were submitted to BODC in .xls files containing sample metadata and concentrations of individual contaminants in blubber samples taken from each animal. Concentrations of standard combinations of congeners were also included. Data received by BODC were transferred into a template whose form had been agreed between BODC and the data originator. The data were then loaded to the BODC database using established BODC data banking procedures. No changes were made to the data during loading. Each contaminant concentration was mapped to an appropriate parameter code with exception of standard combinations of congeners. All values are wet weight concentrations per lipid proportion in the blubber of live, post-weaned pups with a correction to weaning, as described above. Note that the number of decimal places for a particular contaminant may vary between individuals. The originator has stated that, given the magnitude and biological significance of the concentrations, it is valid to round all values to one decimal place for the sake of consistency, should data users wish to do so.

Instrument(s) used to collect data: gas chromatograph mass spectrometers.