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The aim of the present study was to investigate the uptake of 16 PAHs by willow (Salix viminalis) from soil amended with contaminated sewage sludge. Uptake experiments were conducted on field plots using sludge applications of 0, 30, 75, 150, 300, and 600 Mg ha −1 . The total PAH content of control soil and sludge were 49.6 µg kg −1 and 5713 µg kg −1 , respectively. The concentrations for the 16 PAHs listed as priority pollutants were measured for soil and plant tissue samples obtained at 0.5, 1.5, 2.5, and 3.5 years. Soil total PAH content decreased significantly within the first half year, followed by minimal changes over the subsequent three years of treatment. PAH analysis was carried out on a HPLC-UV. Total PAH content in control plants was 3.6-7.3 µg kg −1 for shoots and 13-27 µg kg −1 for leaves. Treated plant tissue content was higher with shoots and leaves containing ∼5.5-17.6 and 13.5-33.8 µg kg −1 , respectively. Plant total PAH content did not show a significant trend relative to controls with respect to time. However, uptake did increase in relation to an increased sludge application. Bioconcentration factors (BCF), adjusted by control values, were calculated for total PAH content. BCF values were highest for the initial sampling (6 months) and did not show a significant temporal relationship. BCF values did decrease with increasing sludge application. With respect to individual PAHs, elevated plant tissue concentrations were measured for "light" PAH (e.g. naphthalene, phenanthrene, acenaphthalene) with leaf BCF values correlated with solubility and organic partitioning coefficients.

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The aim of the present study was an evaluation of the influence of the addition of different sewage sludge doses on the uptake of polycyclic aromatic hydrocarbons from fertilized soil. Sewage sludge was introduced into the soil in the following doses: 30, 75, 150, 300, and 600 Mg/ha. The content of polycyclic aromatic hydrocarbons (PAH) was determined by means of HPLC-UV method. The addition of increasing doses of sludge into the soil resulted in a gradual increase in the amount of the polycyclic aromatic hydrocarbons contained therein. During the period of the study, continuous changes in the content of all the compounds studied were found in all the experimental variants. Finally, on the last day of the study, the highest degree of degradation (73%) of 16 PAHs' sum (US EPA) was noted for sludge doses of 30 and 300 Mg/ha. In the case of individual PAHs, the change in their content differed and clearly depended on the sewage sludge dose. The introduction of sewage sludge into the soil influenced the increase of the sum of 16 PAHs in the plants grown in this soil. The influence mentioned above depended on the sewage sludge dose and the plant species grown, as well as the PAH content in the soil. The evaluation of individual PAHs in plants showed an increase in their content with the increase of the amount of sewage sludge. A statistically significant increase in their content was most often observed for sewage sludge doses above 150 Mg/ha. Moreover, it was found that fertilization of the soil with sewage sludge resulted in pollution of the plants with PAHs of high molecular weight.