A 25-year record of polycyclic aromatic hydrocarbons in soils amended with sewage sludges
Résumé
We studied polycyclic aromatic hydrocarbons (PAHs) in crop soils amended with 1000 tonnes dry weight of sewage sludges per 10,000m2 from 1974 to 1992, then after sludges addition from 1993 to 1999. The absence of variations of total PAHs levels of control soils, averaging at 123µg/Kg, shows the absence of horizontal contamination. During sludges addition, the total PAHs levels in amended soils increased from 232 to 402µg/Kg. Seven years after sludges addition, it decreased to 275µg/Kg, which is still more than twice the levels of control soils. This finding shows that sludges PAHs are preserved in crop soils for long periods of time, on a human scale.
Origine : Fichiers produits par l'(les) auteur(s)
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