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Bioaerosols in homes without visible mold growth: Relationship between indoor and outdoor levels determined by different methods.

机译：没有可见霉菌生长的房屋中的生物气溶胶：通过不同方法确定的室内和室外水平之间的关系。

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The objectives of this dissertation are (1) to quantify indoor-to-outdoor (I/O) ratios of bioaerosols including actinomycetes, fungi, and pollen in single family homes using the microscopic spore counts of filter samples, (2) to investigate the relationship between indoor and outdoor (1→3)-beta-D-glucan concentrations as well as to compare the I/O ratio obtained based on (1→3)-beta-D-glucan analysis to that obtained from microscopic counts for fungal spores and pollen grains for the overall human exposure to bioaerosols, and (3) to characterize the culturability (the ratio of the culturable concentration of airborne fungi to total fungal spore concentration) for indoor and outdoor airborne fungi.; Air samples were collected for 24 hours with a Button(TM) Personal Inhalable Aerosol sampler inside and outside of eleven homes located in the Cincinnati, Ohio area. Measurements were conducted over five consecutive days at each home. The selected homes were free of visible mold growth. The sampling period was between Spring 2004 and Fall 2005. Three different analysis methods were utilized in order to quantify the indoor and outdoor level of (1→3)-beta-D-glucan, actinomycetes, culturable fungi, pollen, and total fungal spores (i.e., culturable analysis for actinomycetes and culturable fungi, microscopic counting for total fungal spores and pollen, and the kinetic chromogenic Limulus Amebocyte Lysate (LAL) method for the (1→3)-beta-D-glucan concentration).; The data for the first and second objective regarding the relationship between indoor and outdoor bioaerosols were obtained by conducting two studies. The first study found that the indoor concentration of fungal spores and pollen followed their outdoor concentrations while indoor levels were mostly lower than the outdoor ones. The I/O ratio of total fungal spores (median=0.35) in six homes was greater than that of pollen grains (median=0.03). The low I/O ratios obtained for pollen during the peak ambient pollination season (spring) suggest that only a small fraction penetrated from the outdoor to the indoor environments. This is attributed to the larger size of pollen grains in comparison to other bioaerosols. Higher indoor concentration levels and variability in the I/O ratio observed for airborne fungi may be associated with indoor sources and/or higher outdoor-to-indoor penetration of fungal spores compared to pollen grains. The concentration of culturable actinomycetes was mostly below the detection limit. The median indoor/outdoor ratio (I/O) for actinomycetes was 2.86.; The second study demonstrated that the I/O ratio of (1→3)-beta-D-glucan concentration was marginally greater than that calculated based on the combined number concentration of fungal spores and pollen. This suggests that (1→3)-beta-D-glucan data are affected not only by intact spores and pollen grains but also by the airborne fragments of fungi, pollen, and plant material, which are not accounted for by traditional enumeration methodologies. Since the (1→3)-beta-D-glucan level may elucidate the total exposure to fungal spores, pollen, and fungal fragments, its I/O ratio may be used as a risk marker for mold and pollen exposure in indoor environments.; The third objective was to investigate the culturability of airborne fungi. The indoor and outdoor concentrations of culturable and total fungal spores were found to significantly correlate. The indoor and outdoor median culturabilities of fungi were 55% and 25%, respectively. Among the seasons, the highest indoor and outdoor culturability of fungi was observed in the fall. Among predominant genera of fungi Cladosporium had the highest median value of culturability (38% and 33% for indoor and outdoor, respectively) followed by Aspergillus/Penicillium (9% and 2%). Increased culturability of fungi inside the homes may have important implications because of the potential increase of allergens from viable spores and the possible p
机译：本文的目的是（1）使用过滤样品的显微孢子计数来量化单个家庭中包括放线菌，真菌和花粉在内的生物气溶胶的室内/室外（I / O）比，（2）研究与室外（1→3）-β-D-葡聚糖浓度之间的关系以及将基于（1→3）-β-D-葡聚糖分析获得的I / O比与从真菌的显微计数获得的I / O比进行比较（a）表征室内和室外空气传播真菌的可培养性（空气传播真菌的可培养浓度与总真菌孢子浓度之比）；在位于俄亥俄州辛辛那提地区的11处房屋内外使用Button™个人可吸入式气雾取样器收集空气样本24小时。在每个家庭中连续五天进行测量。选定的房屋没有可见的霉菌生长。采样期为2004年春季至2005年秋季。采用三种不同的分析方法来量化（1→3）-β-D-葡聚糖，放线菌，可培养真菌，花粉和总真菌孢子的室内和室外水平。 （即，对放线菌和可培养真菌的可培养分析，对真菌总孢子和花粉的显微计数，对（1→3）-β-D-D-葡聚糖浓度进行动力学发色Li变形细胞溶解液（LAL）法）；通过进行两项研究，获得了关于室内和室外生物气溶胶之间关系的第一个和第二个目标的数据。第一项研究发现，室内真菌孢子和花粉的浓度跟随其室外浓度，而室内水平大多低于室外。六个家中总真菌孢子的I / O比（中值= 0.35）大于花粉粒的I / O比（中值= 0.03）。在高峰环境授粉季节（春季）花粉获得的低I / O比表明，只有一小部分从室外渗透到室内环境。这归因于与其他生物气溶胶相比，花粉颗粒的尺寸更大。与花粉粒相比，较高的室内浓度水平和通过空气传播的真菌观察到的I / O比的变化可能与室内来源和/或真菌孢子从室外到室内的较高渗透有关。可培养放线菌的浓度大多低于检测极限。放线菌的室内/室外中位数比（I / O）为2.86。第二项研究表明，（1→3）-β-D-葡聚糖浓度的I / O比例略高于根据真菌孢子和花粉的总浓度计算得出的I / O比例。这表明（1→3）-β-D-葡聚糖数据不仅受到完整的孢子和花粉粒的影响，还受到真菌，花粉和植物材料的空气传播碎片的影响，而传统的枚举方法并未对此进行解释。由于（1→3）-β-D-葡聚糖水平可以阐明真菌孢子，花粉和真菌碎片的总暴露量，因此其I / O比可以用作室内环境中霉菌和花粉暴露的风险指标。 ;第三个目标是研究空气传播真菌的可培养性。发现室内和室外可培养真菌孢子和总真菌孢子的浓度显着相关。室内和室外真菌的中位数可培养性分别为55％和25％。在各个季节中，秋季观察到的真菌在室内和室外的可培养性最高。在真菌的主要属中，隐孢子虫的可培养性中值最高（室内和室外分别为38％和33％），其次是曲霉/青霉菌（9％和2％）。家庭中真菌的可培养性提高可能具有重要意义，因为活孢子可能会增加过敏原，并可能导致细菌

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