title: PAH dynamics in roadside environments: Influence on the consistency of diagnostic ratio values and ecosystem contamination assessments.
abstract: Roadside contamination (of air, soils and organisms) by polycyclic aromatic hydrocarbons (PAHs) was examined in an arable field and a mature forest (central France). Measured contents accounted for minute fractions of the cumulative vehicular exhaust emissions. The fate of vehicular PAHs was affected by many factors, including: atmospheric load dispersal, deposition on soils and vegetation, incorporation into water and organic matter cycles, and accumulation in species. Given these empirical results, we evaluated the consistency of a set of well-known diagnostic ratios. This effort has revealed that: i) most diagnostic ratio values vary considerably across roadside samples, including exhaust emissions; and ii) the first few meters from the carriageway or the road verge/forest interface or remote areas where surface water accumulates actually define turning or inflection points in the ratio profiles. These variations constitute a major obstacle to delimitating the extent of roadside contamination due to PAHs, in addition to raising questions over the applicability of ratios routinely used to designate sources. New ratios, namely (Flt+BkF)/(Pyr+BbF) and (Flt+BkF+BghiP)/Σ10PAH, have been specifically developed to address this challenge. The higher consistencies exhibited among environmental compartments as well as between surface soil and exhaust emissions still yield differentiated values relative to several industrial sources.
authors.affiliation: LUNAM Université, Ifsttar, AME, EASE, F-44341 Bouguenais, France; ADEME en Pays de la Loire, F-49001 Angers, EU, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Clément
authors.affiliation: LUNAM Université, Ifsttar, AME, EASE, F-44341 Bouguenais, France. Electronic address: bogdan.muresan-paslaru@ifsttar.fr.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Muresan
authors.affiliation: INRA, UMR 1402 EcoSys, RD 10, F-78026 Versailles, EU, France.
authors.forename: Mickael
authors.initials: M
authors.lastname: Hedde
authors.affiliation: LUNAM Université, Ifsttar, AME, EASE, F-44341 Bouguenais, France.
authors.forename: Denis
authors.initials: D
authors.lastname: François
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D017753:Ecosystem; D004784:Environmental Monitoring; D005602:France; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D001335:Vehicle Emissions / Q000032:analysis
chemical_list: D000393:Air Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D001335:Vehicle Emissions
keywords: Diagnostic ratios; Leaching; Organic matter; PAH; Roadside contamination