Particle-size distribution and gas/particle partitioning of atmospheric polybrominated diphenyl ethers in urban areas of Greece.

Ambient concentrations, gas/particle partitioning and particle-size distribution of polybrominated diphenyl ethers (PBDEs) were investigated in two urban areas (Athens and Heraklion) of Greece. Atmospheric (gas+particle) concentrations of summation operatorPBDE varied from 21 to 30 pg m(-3) in the center of Athens and from 4 to 44 pg m(-3) in the suburbs of Heraklion. A predominance of particulate PBDEs was observed in Athens (71-76% in particles), whereas the opposite was evident in Heraklion (69-92% in gas phase). In both urban areas, PBDE particle-size distribution featured a distinct enrichment in smaller particles. A similar trend was also observed in aerosols of a background marine site. For all sampling sites, more than 46% of summation operatorPBDE was associated with particles of <0.57 microm in diameter. Our results imply that particulate PBDEs may have long atmospheric residence time and they may be capable of reaching the deeper parts of the human respiratory system.