Bałabański Tomasz, Biedunkiewicz Anna, Jastrzębski Jan P
Department of Microbiology and Mycology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowski 1A St., 10-719 Olsztyn, Poland.
The Center for the Popularization of Science and Innovation of the University of Warmia and Mazury in Olsztyn ″Kortosfera″, Dybowski 11A St., 10-723 Olsztyn, Poland.
Pathogens. 2025 Jul 29;14(8):744. doi: 10.3390/pathogens14080744.
Yeasts possess a range of environmental adaptations that allow them to colonize soil and sand. They can circulate seasonally between different components of lake ecosystems, including beach sand, water, and the coastal phyllosphere. The accumulation of people on beaches promotes the development and transmission of yeasts, posing an increasing sanitary and epidemiological risk. The aim of this study was to determine the species and quantitative composition of potentially pathogenic and pathogenic yeasts for humans present in the sand of supervised and unsupervised beaches along the shores of lakes in the city of Olsztyn (northeastern Poland). The study material consisted of sand samples collected during two summer seasons (2019; 2020) from 12 research sites on sandy beaches of four lakes located within the administrative boundaries of Olsztyn. Standard isolation and identification methods used in diagnostic mycological laboratories were applied and are described in detail in the following sections of this study. A total of 259 yeast isolates (264, counting species in two-species isolates separately) belonging to 62 species representing 47 genera were obtained during the study. Among all the isolates, five were identified as mixed (two species from a single colony). Eight isolated species were classified into biosafety level 2 (BSL-2) and risk group 2 (RG-2). The highest average number of viable yeast cells was found in sand samples collected in July 2019 (5.56 × 10 CFU/g), August, and September 2020 (1.03 × 10 CFU/g and 1.94 × 10 CFU/g, respectively). The lowest concentrations were in samples collected in April, September, and October 2019, and October 2020 (1.48 × 10 CFU/g, 1.47 × 10 CFU/g, 1.40 × 10 CFU/g, and 1.40 × 10 CFU/g, respectively). The results indicate sand contamination with yeasts that may pose etiological factors for human mycoses. In light of these findings, continuous sanitary-epidemiological monitoring of beach sand and further studies on its mycological cleanliness are warranted, along with actions leading to appropriate legal regulations.
酵母具有一系列环境适应性，使其能够在土壤和沙子中定殖。它们可以在湖泊生态系统的不同组成部分之间季节性循环，包括沙滩、水和沿海叶际。海滩上人群的聚集促进了酵母的生长和传播，带来了日益增加的卫生和流行病学风险。本研究的目的是确定在波兰东北部奥尔什丁市湖泊沿岸受监督和不受监督的海滩沙子中存在的对人类具有潜在致病性和致病性的酵母的种类和定量组成。研究材料包括在两个夏季（2019年；2020年）从奥尔什丁行政边界内四个湖泊的沙滩上的12个研究地点采集的沙子样本。采用了诊断真菌学实验室使用的标准分离和鉴定方法，本研究的以下部分将详细描述这些方法。在研究期间共获得259株酵母分离株（若将两菌种分离株中的菌种分别计算则为264株），属于47个属的62个种。在所有分离株中，有5株被鉴定为混合株（来自单个菌落的两个种）。8个分离种被归类为生物安全2级（BSL - 2）和风险组2级（RG - 2）。在2019年7月采集的沙子样本中发现的活酵母细胞平均数量最高（5.56×10 CFU/g），2020年八月和九月的样本中活酵母细胞平均数量分别为1.03×10 CFU/g和1.94×10 CFU/g。最低浓度出现在2019年4月、9月和10月以及2020年10月采集的样本中（分别为1.48×10 CFU/g、1.47×10 CFU/g、1.40×10 CFU/g和1.40×10 CFU/g）。结果表明沙子受到酵母污染，这些酵母可能是人类真菌病的病因。鉴于这些发现，有必要对海滩沙子进行持续的卫生流行病学监测，并对其真菌学清洁度进行进一步研究，同时采取行动制定适当的法律法规。
