Concentrations of polybrominated diphenyl ethers (PBDEs) in sparrowhawk (Accipiter nisus) eggs in the UK

Data generated through the Predatory Bird Monitoring Scheme (PBMS) (http://pbms.ceh.ac.uk/) Egg sampling and analysis. Failed or abandoned sparrowhawk eggs were taken from nests by licensed egg collectors and archived as part of the monitoring activities of the Predatory Bird Monitoring Scheme (PBMS) in the UK. Egg weight, length and breadth were measured and the eggs were then blown or cracked open. The shells were washed, air-dried and reweighed, while the egg contents were homogenised and stored in glass jars at -20oC until analysed. Samples were selected from the PBMS archive for PBDE analysis based on the criteria of covering the longest temporal period in eggs from the smallest possible geographical area, which was found to be the region of England directly east and within 250 km of the Welsh border. Sampling years were determined by the availability of eggs in the archive, the criterion being that three to five eggs, each from a different nest, were available for analysis for each sampling year. There were sufficient eggs for 10 sampling years that spanned the period 1985-2007. When more than one egg was available from any given nest, the egg for analysis was selected at random as laying order was not known.