Assessment of physicochemical and biochemical factors of urban street dust

Studies concerned the composition of street cleansing residue (municipal waste with code 20 03 03) collected and accumulated on mound. The contents of macro- (C, P, S) and microelements (Zn, Cu, Pb, Ni, Cr, Mn, Fe) as well as enzymatic activity (dehydrogenase, catalase, alkaline and acid phosphatase, arylsulfatase) were determined in order to consider this material as a source of nutrients in agriculture. The study showed that the stored material consists mainly of mineral particles, poor in organic matter (mean content 2.905 g/kg) and fine fraction (particles of diameter less than 2 mu m did not exceed 2 wt. %), with alkaline pH. Elevated levels of heavy metals (Cu, Pb, Ni, Cr, Mn and Fe) indicate that street cleaning residue is contaminated with these metals. In spite of relatively high content of phosphorus (mean 52.08 mg/kg) analyzed material should not be used for soil amendment as a source of P for plants, because of the accumulation of heavy metals, and also high contents of S-SO₄^2- (mean 56.38 mg/kg). Furthermore, low biological index fertility (BIF) calculated on the base of enzymatic activity of the collected waste, indicates that analyzed material has low ability to fulfil nourishing plant needs and might be a threat to the environment.