An investigation into the occurrence and distribution of polycyclic aromatic hydrocarbons in two soil size fractions at a former industrial site in NE England, UK using in situ PFE-GC-MS.
Polycyclic aromatic hydrocarbon (PAH) concentrations were determined in 16 topsoils (0-10 cm) collected across the site of a former tar works in NE England. The soils were prepared in the laboratory to two different particle size fractions: <250 μm (fraction A) and >250 μm to <2 mm (fraction B). Sixteen priority PAHs were analysed in the soils using in situ pressurised fluid extraction (PFE) followed by gas chromatography-mass spectrometry (GC-MS). The average total PAH concentration in the soils ranged from 9.0 to 1,404 mg/kg (soil fraction A) and from 6.6 to 872 mg/kg (soil fraction B). These concentrations are high compared with other industrially contaminated soils reported in the international literature, indicating that the tar works warrants further investigation/remediation. A predominance of higher-molecular-weight compounds was determined in the samples, suggesting that the PAHs were of pyrogenic (anthropogenic) origin. Statistical comparison (t-test) of the mean total PAH concentrations in soil fractions A and B indicated that there was a significant difference (95% confidence interval) between the fractions in all but two of the soil samples. Additionally, comparisons of the distributions of individual PAHs (i.e. 16 PAHs × 16 soil samples) in soil fractions A and B demonstrated generally higher PAH concentrations in fraction A (i.e. 65.8% of all individual PAH concentrations were higher in soil fraction A). This is important because fraction A corresponds to the particle size thought to be most important in terms of human contact with soils and potential threats to human health.
Lorenzi
Damien
D
School of Applied Sciences, University of Northumbria at Newcastle, Ellison Building, Newcastle-upon-Tyne, NE1 8ST, UK.
Cave
Mark
M
Dean
John R
JR
D005591:Chemical Fractionation; D002845:Chromatography; D004739:England; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D010316:Particle Size; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000737:chemistry; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry
D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants