Assessment of soil and grass Polycyclic Aromatic Hydrocarbon (PAH) contamination levels in agricultural fields located near a motorway and an airport

Along motorways and airports, PAHs produced by vehicle exhausts can be deposited on grass and soil, leading to a risk of contamination through the food chain via the ruminant. Grass and soil were collected near the verge of a road (10 m) and a take-off strip (50 m). Analyses detected the 16 PAHs listed by the US Environmental Protection Agency in both sites and both grass and soil. The motorway site is about four times more contaminated (188 ng/g DW for grass) than the airport site (69 ng/g DW for grass) and carcinogenic compounds are present in both grass and soil. Furthermore, the part consisting of low molecular weight, and four and less than four ring compounds is higher in grass (36%) than in soil, where high molecular weight and more than four ring compounds represent 86% of the total PAHs.