Plant and Microbial Biology, University of California, Berkeley, California, USA
California Department of Public Health, Richmond, California, USA.
Appl Environ Microbiol. 2020 Aug 18;86(17). doi: 10.1128/AEM.01047-20.
Identifying microbial indicators of damp and moldy buildings remains a challenge at the intersection of microbiology, building science, and public health. Sixty homes in New York City were assessed for moisture-related damage, and three types of dust samples were collected for microbiological analysis. We applied four approaches for detecting fungal signatures of moisture damage in these buildings. Two novel targeted approaches selected specific taxa, identified by hypotheses, from the broad mycobiome as detected with amplicon sequencing. We investigated whether (i) hydrophilic fungi (i.e., requiring high moisture) or (ii) fungi previously reported as indicating damp homes would be more abundant in water-damaged rooms/homes than in nondamaged rooms/homes. Two untargeted approaches compared water-damaged to non-water-damaged homes for (i) differences between indoor and outdoor fungal populations or (ii) differences in the presence or relative abundance of particular fungal taxa. Strong relationships with damage indicators were found for some targeted fungal groups in some sampling types, although not always in the hypothesized direction. For example, for vacuum samples, hydrophilic fungi had significantly higher relative abundance in water-damaged homes, but mesophilic fungi, unexpectedly, had significantly lower relative abundance in homes with visible mold. Untargeted approaches identified no microbial community metrics correlated with water damage variables but did identify specific taxa with at least weak positive links to water-damaged homes. These results, although showing a complex relationship between moisture damage and microbial communities, suggest that targeting particular fungi offers a potential route toward identifying a fungal signature of moisture damage in buildings. Living or working in damp or moldy buildings increases the risk of many adverse health effects, including asthma and other respiratory diseases. To date, however, the particular environmental exposure(s) from water-damaged buildings that causes the health effects have not been identified. Likewise, a consistent quantitative measurement that would indicate whether a building is water damaged or poses a health risk to occupants has not been found. In this work, we tried to develop analytical tools that would find a microbial signal of moisture damage amid the noisy background of microorganisms in buildings. The most successful approach taken here focused on particular groups of fungi-those considered likely to grow in damp indoor environments-and their associations with observed moisture damage. With further replication and refinement, this hypothesis-based strategy may be effective in finding still-elusive relationships between building damage and microbiomes.
鉴定潮湿和发霉建筑物中的微生物指标仍然是微生物学、建筑科学和公共卫生交叉领域的一项挑战。对纽约市的 60 户家庭进行了与潮湿相关的损害评估，并采集了三种类型的灰尘样本进行微生物分析。我们应用了四种方法来检测这些建筑物中与水分有关的损害的真菌特征。两种新的靶向方法从广泛的真菌组中选择了特定的类群，这些类群是通过扩增子测序确定的假设。我们研究了以下两种情况：(i)亲水真菌（即需要高水分）或 (ii) 以前报告表明潮湿家庭的真菌是否会在潮湿的房间/家庭中比在未损坏的房间/家庭中更为丰富。两种非靶向方法将潮湿的家庭与未潮湿的家庭进行比较，以比较(i)室内和室外真菌种群之间的差异或 (ii)特定真菌类群的存在或相对丰度的差异。在一些采样类型中，一些靶向真菌群与损伤指标之间存在很强的关系，尽管并非总是按照假设的方向。例如，对于真空样本，亲水真菌在潮湿的家庭中的相对丰度显著更高，但出乎意料的是，在有可见霉菌的家庭中，嗜温真菌的相对丰度显著更低。非靶向方法未确定与水分损害变量相关的微生物群落指标，但确实确定了与潮湿家庭至少具有微弱正相关的特定类群。尽管这些结果表明水分损害与微生物群落之间存在复杂的关系，但表明靶向特定真菌可能是识别建筑物水分损害真菌特征的一种潜在途径。在潮湿或发霉的建筑物中生活或工作会增加许多不良健康影响的风险，包括哮喘和其他呼吸道疾病。然而，迄今为止，尚未确定导致健康影响的从潮湿建筑物中产生的特定环境暴露。同样，也没有发现可以指示建筑物是否受潮或对居住者构成健康风险的一致的定量测量。在这项工作中，我们试图开发分析工具，以便在建筑物中微生物的嘈杂背景中找到水分损害的微生物信号。这里采用的最成功的方法侧重于特定的真菌群-那些被认为可能在潮湿的室内环境中生长的真菌群-以及它们与观察到的水分损害的关联。通过进一步的复制和改进，这种基于假设的策略可能会有效地发现建筑物损坏和微生物组之间仍然难以捉摸的关系。
