Peanut oil may be used as a natural, non-toxic, cost-effective and biodegradable extractant for decontamination of polycyclic aromatic hydrocarbon (PAHs)-contaminated soil. Extraction efficiency was >90% when peanut oil at concentrations of 2.5-20% was used to remove anthracene from garden soil. Optimal pH for these extractions was 6 and 7. When soil spiked with a combination of 10 PAHs at 100 mug/g was extracted with peanut oil at different temperatures (20-60 degreesC), total PAH extraction efficiency increased from 51.5% at 20 degreesC to 81.4% at 60 degreesC. A double extraction of weathered soil from a creosote-contaminated site using 5% peanut oil, followed by another 5% oil was better than a single 10% oil extraction. Based on the results, a process for the treatment of PAH-contaminated soil was conceptualized. (C) 2003 Elsevier Ltd. All rights reserved.