Szukana fraza: [Abstract = "Sewage sludges were taken from a municipal wastewater treatment plant. Under experimental conditions the half\-lives of individual compounds were diversed. In biotic samples half life of hydrocarbons was in the range of 19 to 368 days. Half\-life of PAHs in abiotic sewage sludges was in the range of 31 to 2961 days. The most persistent were phenanthrene."]