Assessment of biological colonization of historic buildings in the former Auschwitz II-Birkenau concentration camp

The objective of this study was to assess biological colonization of wooden and brick buildings in the former Auschwitz II-Birkenau concentration camp, and to identify the organisms colonizing the examined buildings. Microbiological analysis did not reveal increased microbial activity, and the total microbial count of the barrack surfaces did not exceed 10(3) CFU/100 cm(2). However, certain symptoms of biodegradation of the buildings were observed. The predominant microflora consisted of bacteria of the genera Bacillus, Sporosarcina, Pseudomonas, Micrococcus, Streptomyces, and Staphylococcus, as well as fungi of the genera Acremonium, Cladosporium, Alternaria, Humicola, Penicillium, and Chaetomium. The microflora patterns varied both in wooden and brick buildings. The structural elements of wooden and brick barracks, and especially of the floors and lower parts of bathroom walls, were infected by cyanobacteria and algae, with the most numerous being cyanobacteria of the genera Scytonema, Chroococcus, Gloeothece, Leptolyngbya, diatoms of the genus Diadesmis, and chlorophytes of the genera Chlorella and Apatococcus. The outer surfaces of the examined buildings were primarily colonized by lichens and bryophytes, with nearly 30 species identified. The dominant species of lichens belonged to the genera Candelariella, Caloplaca, Lecanora, Lecidea, Lepraria, Physcia, and Protoparmeliopsis, and those of bryophytes to the genera Bryum, Ceratodon, Marchantia, and Tortula. The quantity and species diversity of lichens and mosses were much lower in wooden barracks than in brick ones. The external surfaces of those barracks were only affected by Lecanora conizaeoides, Lecanora symmicta, Lepraria cf. incana, and Strangospora pinicola. The study results revealed vast biodiversity among the species colonizing historic buildings. The presence of these groups of organisms, resulting from their natural expansion in the environment, is undesirable, as their excessive growth and spread may lead to progressive biodegradation of buildings. Our assessment of biological contamination will enable the development of a disinfection and conservation plan for the examined buildings

Biodeterioration symptoms of internal part of buildings (numerical value of deterioration in a 4-point scale).

<p>a) the middle part of building, damages of the floor (3– ground floor: intensive changes, 2– walls: moderate changes); b) block master’s room and storeroom, damages of the wood floor, algae and cyanobacteria colonization (3– ground floor: intensive changes, 1– walls: small changes); c) bunk bed partitions, bulging and crumbling plaster (3– intensive changes); d) damages of bunk beds board caused by wood-decaying fungi (2– moderate changes, locally).</p

Microbial contamination of building surfaces [CFU 100 cm⁻²].

<p>R - range; M - mean; SD - standard deviation; nd - not detected; nc - not calculated.</p><p>Microbial contamination of building surfaces [CFU 100 cm⁻²].</p

Temperature inside the studied buildings [°C]; SD values did not exceed ±1.4°C.

<p>Temperature inside the studied buildings [°C]; SD values did not exceed ±1.4°C.</p

Brick barracks in section BI (photo by Ł. Szoblik).

<p>Brick barracks in section BI (photo by Ł. Szoblik).</p

Technical condition of the buildings and the extent of deterioration.

<p>(+) element present; (*) element damaged; A - algae and cyanobacteria; B - bryophytes; L - lichens; F - wood-decaying fungi; G - ground floor; W - wall; P - bunk beds.</p><p>Scale: 0- no changes, 1- small changes (up to 20% of the area), 2- moderate changes (from 20% to 50% of the area), 3- intensive changes (over 50% of the area).</p><p>Technical condition of the buildings and the extent of deterioration.</p

Moisture content and microbial counts in mineral materials depending on distance from the ground: ▴ moisture content [%]; □ number of microorganisms [log CFU g⁻¹].

<p>Moisture content and microbial counts in mineral materials depending on distance from the ground: ▴ moisture content [%]; □ number of microorganisms [log CFU g⁻¹].</p