The objectives of the study were the identification of the source of contamination of
soils and estimation of the potential
cancer risk that may be caused by contact with
soils situated in the vicinity of
biochar production sites. Samples of
soils collected in the immediate vicinity of traditional
biochar-producing plants, located within the area of the Bieszczady National Park (Poland), were analysed for the content of
polycyclic aromatic hydrocarbons (PAHs). The sum of the content of 16 PAHs varied within the range of 1.80-101.3 μg/g, exceeding the norms permitted in many European countries. The calculated coefficients on the basis of which one can determine the origin of PAHs (molecular diagnostic ratios) demonstrated that the potential source of PAHs in the
soils may be processes related with the production of
biochar. Estimation on the basis of the results of incremental lifetime
cancer risks (ILCRs) within the range of 2.33 · 10(-4)-1.05 · 10(-1) indicated that the
soils studied may constitute a significant
cancer risk for persons who have contact with them. The values of ILCRS should be considered as at least high, which permits the conclusion that sites of that type may create a hazard to human health.