Polycyclic aromatic hydrocarbons in highway plants and soils. Evidence for a local distillation effect

Carine Bryselbout (1) , Pascale Henner (2) , Jean Carsignol , Eric Lichtfouse (3)

1 ANDRA - Agence Nationale pour la Gestion des Déchets Radioactifs
2 IRSN - Institut de Radioprotection et de Sûreté Nucléaire
3 ASD - Agronomy for Sustainable Development

Poa trivialis grasses and soils from the side slope of a high-traffic highway were analysed for their PAH content by gas chromatography coupled to mass spectrometry. The ratios of volatile, low-molecular weight PAHs versus high-molecular weight PAHs increase with side slope height. For instance, naphthalene/pyrene values increase from 0.3 to 3.4 in plants. Acenaphthene/fluoranthene values increases from 0.017 to 0.123 in soils. Moreover, soil PAHs can be classified into two categories according to variations of absolute concentrations with height : low-molecular weight PAHs showing an increase and high-molecular weight PAHs showing a decrease. These results demonstrate the occurrence of an atmospheric distillation effect which favour the concentration of high-molecular weight PAHs near the PAH source. Environmental implications of a such phenomenon are discussed.

Mots clés: soil; plant; PAH; road; highway; combustion; fossil fuel pollution; distillation; grass; air; naphthalene; acenaphthylene; acenaphthene; fluorene; phenanthrene; anthracene; fluoranthene; pyrene; chrysene; benzofluoranthene; benzo(a)pyrene; indenopyrene; benzoperylene; dibenzanthracene

Domaines: Science des sols; Milieux et Changements globaux

Carine Bryselbout, Pascale Henner, Jean Carsignol, Eric Lichtfouse. Polycyclic aromatic hydrocarbons in highway plants and soils. Evidence for a local distillation effect. Analusis, 2000, 28 (4), pp.290-293. ⟨hal-00263426⟩