[Determination of the benzo(a)pyrene content of microbial biomasses and protein feed]

A method for the fluorimetric determination of benzo(a)pyrene content is presented consisting of classical clean-up steps. The method was applied to microbial biomasses and different feed stuffs. The investigated yeasts grown on carbohydrates keep the limit of 5 ppb benzo(a)-pyrene recommended by the IUPAC. Yeast samples of the VEB Petrolchemisches Kombinat Schwedt grown on petroleum distillate have a constant quality with benzo(a)pyrene contents at 1 ppb. A selection of bacterial biomasses shows also contents less than 5 ppb. The benzo(a)pyrene contents of biomasses cultivated on liquid manure exceed the given limit.