Airborne and soil microfungi as contaminants of stone in a hypogean cemetery

In a hypogean Jewish cemetery in Bratislava containing cemetery soil and tombstones, the types of fungi on various calcite mineral substrates in dark, cold and constantly moist chambers without direct ventilation and lighting were investigated. The mineral substrates included monomineral limestone, and limestone containing quartz, magnesite, gypsum, micas, feldspar, illite and smectite. The characteristics of the mineral substrates were examined by pH and X-ray-diphractographic analyses. The pH of the substrates in water ranged from 9.71 to 10.33. Structural changes in the substrates were revealed by scanning electron microscope photos. The samples yielded 36 different microfungi. The most common contaminants of the substrates analysed were Acremonium strictum, Alternaria alternata, Aspergillus versicolor, Aureobasidium pullulans, Cladosporium sp., Fusarium sp., Penicillium sp., P. chrysogenum, P. viridicatum, and Trichoderma sp. The investigation has shown that these hard, highly alkaline mineral substrates are susceptible to the growth of microscopic fungi, sporulation and subsequent degradation of the materials.