LAUSR

The article deals with studying the antimicrobial efficiency of finely ground metallurgical slags, such as granulated blast-furnace slag with specific surface areas of 340 (1Sa) and 520 m2/kg (1Sb), air cooled blast-furnace slag (2S), demetallized steel slag (3S), calcareous ladle slag (4S), and copper slag (5S). The efficiency was tested on microbial representatives, such as: Gram-positive bacteria—Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus; Gram-negative bacteria—Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens; yeasts—Candida utilis, Rhodotorula glutinis; and microscopic filamentous fungi—Aspergillus niger, Penicillium funiculosum, Chaetomium globosum, Alternaria alternata, Trichoderma viride, Cladosporium herbarum. The efficiency was determined by dilution methods in agar growth media so that the resulting concentration of the tested slags was 10, 20, 40, and 60%. The antibacterial efficiency of the slags decreased in the order: S4 > S3 > S2 > S1a = S1b > S5, while their anti-yeast efficiency decreased in the order S4 > S1a = S1b = S3 > S2 > S5. Microscopic filamentous fungi were selectively sensitive to the slags; therefore, there is only an approximate order of efficiency of S4 > S3 = S1a = S1b > S5 > S2. Application of metallurgical slags into building materials and products provide them with increasing resistance against biodeterioration.