title: Effects of drying and comminution type on the quantification of Polycyclic Aromatic Hydrocarbons (PAH) in a homogenised gasworks soil and the implications for human health risk assessment.
abstract: This research investigates the effect of nine physical treatment types comprising a serial combination of three drying (air, freeze and oven) and two comminution (milling and sieving) methods on the quantification of PAH in a soil sample from a former gasworks. Results show that treatment type has a significant effect on PAH concentration (p⩽0.05). Naphthalene, 1-methylnaphthalene and 2-methylnaphthalene concentrations were significantly higher for air drying and freeze drying treatments than for oven drying. It is suggested that naphthalene and similarly volatile PAH losses were greater for oven drying due to the application of fanned warm air which is thought to cause volatilisation. Analytical precision was significantly improved for milled samples compared with sieved samples. The reason milling results in greater precision is assigned to the improved solvent extraction efficiency when natural grain size is altered due to crushing. The analytical data were compared to residential generic assessment criteria (GAC) used for risk-based land management. It was shown that the naphthalene GAC was lower than all freeze drying and air drying concentrations but was within the oven drying concentration range, illustrating that a false negative could be concluded during risk evaluation is oven dried data were used. Overall, it is recommended that air drying or freeze drying is a better choice than oven drying if the quantification of low molecular weight PAH forms an important objective of sample characterisation for risk-based land management, otherwise freeze drying and milling is recommended.
authors.affiliation: University of Nottingham, School of Geography, University of Nottingham, Nottingham NG7 2RD, UK; British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK. Electronic address: lgxdjb@nottingham.ac.uk.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Beriro
authors.affiliation: British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK.
authors.forename: Christopher H
authors.initials: CH
authors.lastname: Vane
authors.affiliation: British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Cave
authors.affiliation: University of Nottingham, School of Geography, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: C Paul
authors.initials: CP
authors.lastname: Nathanail
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005612:Freeze Drying; D006801:Humans; D009281:Naphthalenes / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000737:chemistry*; D018570:Risk Assessment; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D013048:Specimen Handling / Q000295:instrumentation
chemical_list: D009281:Naphthalenes; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; C031721:naphthalene; C025968:1-methylnaphthalene; C027384:2-methylnaphthalene
keywords: Drying; Milling; PAH; Physical treatment; Sieving; Soils