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Updated: Aug 15, 2026

Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
[Limit values for polycyclic aromatic hydrocarbons in soil of children's playgrounds--basic criteria and
E Roscher1, B Liebl, U Schwegler
1Landesuntersuchungsamt für das Gesundheitswesen Südbayem, Oberschleissheim.
Abstract:
Elevated concentrations of polycyclic aromatic hydrocarbons (PAK) are often found in the soil of former waste disposal sites, industrial areas, etc. It is desirable and useful to determine orientation values to facilitate and unify the evaluation of contaminations under the aspects of present or planned uses of an area, health protection and decision-making on remedial measures. In the present paper we wish to draw attention to, and discuss problems resulting from, particular characteristics of PAK, e.g. the toxicological property "complete carcinogens" or the necessity of taking into account oral, inhalative and dermal exposure of children on a playground. Based on the discussion, orientation values for benzo[a]pyrene and PAK ("normal" pattern) of 0.5 mg/kg soil and 5 mg/kg soil, respectively, are recommended for top soil of vegetation-free playgrounds. In comparison, deductions carried out by other working groups are presented.

