Assessment of Inhalation Exposures to Indoor and Occupational Aerosols

室内和职业气溶胶吸入暴露评估

• 批准号: 10282158
• 负责人: Donald Beezhold
• 金额: $ 13.58万
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10282158
• 关键词: Address; Aerosols; Agreement; Airway Disease; Area; Asthma; Basidiomycota; Biological Assay; Biological Markers; Child; Consensus; Cryptococcus; DNA Sequence; Detection; Development; Dust; Environment; Event; Exposure to; Floods; Floor; Freezing; Fungal Components; Fungal DNA; Fusarium; Genomics; Goals; Growth; Health; Health Hazards; High Pressure Liquid Chromatography; Home environment; Housing; Hygiene; Hypersensitivity; Hyphae; Immune response; Indoor environment; Inhalation Exposure; Journals; Knowledge; Lung; Manuscripts; Measures; Metabolic; Metabolism; Methodology; Methods; Mission; Modeling; Molds; Mycotoxins; Natural Disasters; Neighborhoods; New York; New York City; Occupational; Organism; Polymerase Chain Reaction; Prevalence; Public Health; Publishing; Reagent; Refrigeration; Reporting; Reproduction spores; Research; Risk; Role; Sampling; Schools; Source; System; Temperature; Time; Toxicology; Water; Yeasts; air sampling; base; built environment; deoxynivalenol; experimental study; exposed human population; fungus; improved; insight; metropolitan; microbial; respiratory health; response; submicron

Exposure Assessment of Indoor and Occupational Aerosols - Consensus reports have identified associations between exposure to damp indoor environments, microbial growth and adverse respiratory health effects. Inhalation exposure of fungal bioaerosols found within these damp contaminated environments continues to be an area of great public concern especially for residents residing in or returning to these water damaged environments following natural disasters or flooding events. To assess the risk of exposure, the development of standard exposure assessment methods to identify and quantify microbial bioaerosols is critical, in order to determine sources, metabolic byproducts and biomarkers of exposure. Building upon the research conducted in previous years, NIOSH continued ongoing projects in FY20 to better understand the adverse health effects caused by fungal exposure. Sequencing-based studies conducted previously have identified fungal yeasts, which are often overlooked, as sources of personal exposure. Basidiomycota yeasts are prominent in indoor contaminated environments, but their role in adverse health effects has remained relatively uncharacterized. To address this knowledge gap, species-specific primers, probes, and a quantitative polymerase chain reaction (qPCR) method were developed to provide the detection and quantification of Vishniacozyma victoriae (syn. Cryptococcus victoriae). This species-specific qPCR assay was then used to detect and quantify V. victoriae in dust samples from homes participating in the New York City Neighborhood Asthma and Allergy Study (NAAS). In addition, the influence of housing factors and health effects associated with V. victoriae exposure in homes of children from low and high asthma prevalence neighborhoods in the New York metropolitan area were examined. The results from this study will provide new insight into the association between fungal yeast exposure and airway diseases. Along with exposure to fungal components including spores, hyphae and submicron fragments, exposure to fungi also includes secondary byproducts of fungal metabolism, such as mycotoxins. In FY20, a manuscript titled “Effect of storage temperature and duration on concentrations of 27 fungal secondary metabolites spiked into floor dust from an office building” was published in the Journal of Occupational and Environmental Hygiene. This manuscript reported that fungal secondary metabolites in floor dust, including mycotoxins, quickly degraded at room temperature, whereas storing them under refrigeration or freezing conditions slowed degradation. This study demonstrated that storage temperature influenced degradation of the metabolites more than storage time. The rapid degradation of the secondary metabolites at room temperature may indicate that the concentrations of those metabolites, especially mycotoxins, are likely to be low in indoor settled dust. NIOSH had previously documented substantial matrix effects associated with the quantification of the metabolites in dust samples using the high-throughput HPLC-MSMS method. A standard addition method to compensate for substantial matrix effects was further investigated in FY20. Currently, the importance of using internal standards in the analysis of multiple fungal metabolites in floor dust samples is being examined by comparing the concentrations of the secondary metabolites measured with internal standards to those without internal standards. In addition to the examination of secondary metabolite storage conditions, experiments to assess stability of standard materials during storage at multiple storage conditions for extended time periods were also completed in FY20. Using the assessment of fungal DNA sequences from 500 dust samples previously collected from 50 schools, the organisms Fusarium graminearum and F. culmorum were identified, along with the mycotoxin, deoxynivalenol, from 48.1% and 83.4% of the samples, respectively. Examination of fungal secondary metabolite profiles for the floor dust samples will continue in FY21.

室内和职业气溶胶暴露评估-共识报告已经确定了潮湿室内环境暴露、微生物生长和不良呼吸健康影响之间的关联。在这些潮湿的污染环境中发现的真菌生物气溶胶的吸入暴露仍然是公众非常关注的领域，特别是对于居住在这些水损害环境中或在自然灾害或洪水事件后返回这些水损害环境的居民。为了评估接触风险，必须制定标准的接触评估方法，以确定和量化微生物生物气溶胶，以确定接触的来源、代谢副产品和生物标志物。在前几年进行的研究的基础上，NIOSH在2020财年继续进行项目，以更好地了解真菌暴露造成的不良健康影响。以前进行的基于测序的研究已经确定了真菌酵母，这是经常被忽视的，作为个人暴露的来源。担子菌酵母菌在室内污染环境中很突出，但它们在不良健康影响中的作用仍然相对不确定。为了解决这一知识缺口，开发了种特异性引物、探针和定量聚合酶链反应（qPCR）方法，以提供维多利亚维氏酵母（Vishniacozyma victoriae）（syn.维多利亚隐球菌）。然后使用该种特异性qPCR测定来检测和定量来自参与纽约市邻里哮喘和过敏研究（NAAS）的家庭的灰尘样品中的维多利亚弧菌。此外，还对纽约大都市区哮喘发病率低和高社区儿童家中与维多利亚弧菌暴露相关的住房因素和健康效应的影响进行了研究。这项研究的结果将为真菌酵母暴露与气道疾病之间的关联提供新的见解。沿着暴露于真菌组分，包括孢子、菌丝和亚微米碎片，暴露于真菌还包括真菌代谢的次级副产物，如真菌毒素。2020财年，《职业与环境卫生杂志》发表了一篇题为“储存温度和持续时间对办公楼地板灰尘中27种真菌次级代谢物浓度的影响”的论文。这份手稿报告说，地板灰尘中的真菌次级代谢产物，包括真菌毒素，在室温下迅速降解，而在冷藏或冷冻条件下储存它们会减缓降解。本研究表明，储存温度对代谢产物降解的影响大于储存时间。次级代谢产物在室温下的快速降解可能表明，这些代谢产物，特别是真菌毒素的浓度可能很低，在室内沉降灰尘。NIOSH先前已经记录了大量的基质效应与使用高通量HPLC-MSMS方法定量粉尘样品中的代谢物相关。2020财年进一步研究了补偿大量基质效应的标准加入法。目前，使用内标物在地板灰尘样品中的多种真菌代谢物的分析的重要性正在检查，通过比较与内标物测量的次级代谢物的浓度，那些没有内标物。除检查次级代谢产物储存条件外，还在2020财年完成了评估标准品在多种储存条件下长期储存期间稳定性的实验。 通过对来自50所学校的500个灰尘样本的真菌DNA序列进行分析，确定了禾谷镰刀菌（Fusarium graminearum）和禾谷镰刀菌（F.结果表明，在48.1%和83.4%的样品中分别鉴定出了沿着的真菌毒素-脱氧雪腐镰刀菌烯醇（deoxynivalenol）。2021财政年度将继续对地板灰尘样本的真菌次级代谢产物谱进行检查。