PAH contamination of western Irish Sea sediments.

Concentrations of the sum of 15 PAHs in 22 surficial sediment samples from the western Irish Sea ranged from below 100 ng g(-1) in sandy sediments to a maximum of 1422 ng g(-1) in the centre of the mud basin. The concentrations are typical of coastal shelf sediments, but greater than those observed for aquatic sediments remote from known anthropogenic sources. Organic C and the % sediment <15 microm were positively correlated with sigmaPAH. sigmaPAH was normalised to organic C and particle size (i.e. expressed as sigmaPAH/C(org) and sigmaPAH/% < 15 microm) and significant relationships were still observed with organic C and % < 15 microm. The results are discussed in the context of using organic C to normalise concentrations of PAHs to assess contamination levels in sediments.