Spatial and temporal patterns of polycyclic aromatic hydrocarbons (PAHs) in eggs of a coastal bird from northwestern Iberia after a major oil spill

This study investigated the spatial and temporal patterns of polycyclic aromatic hydrocarbons (PAHs) in kentish plover (Charadrius alexandrinus) eggs after a major oil spill (Prestige, November 2002) in northwest Iberia. We analysed a total of 77 eggs from 10 breeding localities of the Iberian Atlantic coast, 9 located along the Galician coast (NW Spain) and one in the Ria de Aveiro (Portugal). General linear mixed models did not show a significant effect of the area on the total PAH levels and on each compound, probably due to the spread of pollution caused by the Prestige ship and the industrial and harbour pollutions of the Ria de Aveiro (Portugal). In contrast, the PAH levels were significantly affected by year. The PAH levels decreased from 2004 to 2006 but strongly increase and showed a different pattern of PAH accumulation in 2007. These results may be due to tetra- and pentacyclic compounds from forest fires that occurred during summer 2006.

Research highlights
► PAHs levels in eggs were not significant affected by the distance to Prestige wreck.
► The year had a significant influence on both ΣPAHs and on each of the compounds.
► High molecular weight PAHs in 2007 could be related with coastal forest fires.
► Temporal monitoring of PAHs shows the incidence of unexpected sources of pollution.