A high throughput procedure for polycyclic aromatic hydrocarbons (PAHs) assayed for biodegradation in contaminated soils

This study describes the development of a high throughput procedure for the extraction, purification, and quantification of all 16 polycyclic aromatic hydrocarbons (PAHs) on EPA's priority list, subject to biodegradation assays in a creosote-contaminated soil. We used various combinations of solvents, temperatures, ultrasonication, tumbling, saponification, vacuum centrifugation, adsorption chromatography, gas chromatography, and mass spectrometry to demonstrate that a) individual PAHs were quantified in the soil matrix with coefficient of variations varying between 5 and 28%, b) recovery from a spiked soil was 80% and more for most compounds but dependent on characteristics of the internal standard, c) up to 20 PAH analyses of soil samples can be processed per day by one person, with a reasonably low consumption of solvents, and d) from undetectable levels to >50% of PAHs were biodegraded in 45 days at 23 degreesC in soil samples that were contaminated with creosote more than 35 years ago.