Abstract

The Environmental Relative Moldiness Index (ERMI) is a scale used to compare mold contamination levels in U.S. homes. To create the ERMI scale, a nationally representative set of U.S. homes was selected (n = 1,096). From each of these homes, a standard vacuum-dust sample was collected and then 36 common molds, the 26 Group 1 and 10 Group 2 molds, as grouped for forming the ERMI metric, were quantified using quantitative PCR assays. However, in investigations of mold in homes, it is not always practical or even possible to collect dust using the standard vacuum method. Therefore, we performed a comparative study of dust samples collected in the same homes (n = 151) by the standard vacuum method and by an electrostatic cloth (EC) method. First, floor dust was collected by vacuuming a 2 m² area in the living room and a 2 m² area in a bedroom, directly adjacent to the sofa or bed, for 5 min each with a Mitest sampler-fitted vacuum. Second, immediately after the collection of the vacuum dust sample, an EC dust sample was collected by wiping above-floor horizontal surfaces in the living room and bedroom. Then, the ERMI analysis of each sample was performed by a commercial laboratory. The results showed the average concentrations of 33 of the 36 ERMI molds were not significantly different in the vacuum and EC samples. Also, the average summed logs of the Group 1 molds, Group 2, or ERMI values were significantly (p < 0.001) correlated between the vacuum and EC samples. Logistic regression indicated that an EC sample could identify homes in the highest ERMI quartile 96% of the time by using the same ERMI value cutoff as vacuum sample ERMI value cutoff and 35% of samples proved to be false positives. When it is not practical to obtain the standard vacuum-dust sample, an EC sample can provide a useful practical alternative for ERMI analyses.

摘要

环境相对发霉指数 (ERMI) 是用于比较美国家庭中霉菌污染水平的量表。为了创建 ERMI 量表，选择了一组具有全国代表性的美国家庭 (n = 1,096)。从这些家庭中的每一个，收集标准的真空灰尘样本，然后使用定量 PCR 分析对 36 个普通霉菌、26 个第 1 组和 10 个第 2 组霉菌进行分组，以形成 ERMI 指标。然而，在家庭中的霉菌调查中，使用标准真空方法收集灰尘并不总是可行的，甚至是不可能的。因此，我们通过标准真空方法和静电布 (EC) 方法对在同一家庭 (n = 151) 中收集的灰尘样本进行了比较研究。^{首先，用 2 m 2}吸尘器收集地板灰尘客厅的区域和卧室的 2 m ²区域，直接靠近沙发或床，每个区域使用 Mitest 采样器安装真空吸尘器 5 分钟。其次，在真空尘埃样品采集后，立即通过擦拭客厅和卧室的地上水平表面收集EC尘埃样品。然后，由商业实验室对每个样品进行 ERMI 分析。结果表明，36 个 ERMI 模具中的 33 个的平均浓度在真空和 EC 样品中没有显着差异。此外，第 1 组模具、第 2 组或 ERMI 值的平均总对数显着（p < 0.001) 真空和 EC 样品之间的相关性。Logistic 回归表明，通过使用与真空样本 ERMI 值截止值相同的 ERMI 值截止值，EC 样本可以在 96% 的时间内识别出最高 ERMI 四分位数的房屋，并且 35% 的样本被证明是假阳性。当获得标准真空粉尘样品不切实际时，EC 样品可以为 ERMI 分析提供有用的实用替代方案。