Sea Mammal Research Unit (SMRU) harbour seal contaminants dataset https://portal.medin.org.uk/portal/start.php?tpc=006_95fb6a17fb4a5c9dbe038de6bbc557fb The data set comprises measurements of contaminant concentrations in the blubber of harbour seals. Samples were collected from five populations around the UK coast: the Wash, southeast England; the Tay estuary, southeast Scotland; the Moray Firth, northeast Scotland; Orkney, north Scotland; and Islay and Jura, southwest Scotland. The data were collected between 24 January and 26 October 2003. Seals were captured on land, hauled out with the use of hand-held hoop nets, or caught at sea in tangle nets deployed from boats. After capture, the seals were weighed and sedated, and classified as adult or subadult on the basis of mass and body length measurements. Animals greater than 110 cm standard body length (nose–tail) were considered to be adult and those between 100 and 110 cm as subadult. Animals less than 100 cm were excluded from the study. One dead seal was also included in the analysis. Blubber biopsy samples were collected and 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. The work focused on polybrominated diphenyl ether (PDBE) and polychlorinated biphenyl (PCB) concentrations in seal blubber. PBDEs are the main components of brominated flame retardant chemicals, and both these and PCBs are thought to increase seal mortality. The five seal populations were chosen following differential mortality during the 2002 phocine distemper epidemic in order to determine whether contaminant concentrations had influenced mortality rates associated with that disease. The data were collected by researchers from the Sea Mammal Research Unit (SMRU) at the University of St Andrews and the University of Lancaster Department of Environmental Science. The data are held at the British Oceanographic Data Centre (BODC). 20171003 20110309