Department of Environmental Health, University of Cincinnati, Cincinnati, OH, USA.
Indoor Air. 2013 Apr;23(2):142-7. doi: 10.1111/j.1600-0668.2012.00799.x. Epub 2012 Aug 18.
Fungal exposure may induce respiratory symptoms. The causative agents are compounds in the fungal cell wall. Fragments of microbes may be present in air samples but are not measurable using conventional spore counting or by the determination of viable organisms. This study assesses the proportion of fungal cell biomass and endotoxin in different particle size fractions in air samples from homes. Air samples were collected from 15 homes using a cyclone sampler, collecting particles in three aerodynamic size fractions: <1.0, 1.0-1.8, and >1.8 μm. N-Acetylhexosaminidase (NAHA) was determined as a marker of fungal cell biomass. Endotoxin was determined using the Limulus amebocyte lysate method. NAHA and endotoxin in the size range <1.0 μm comprised up to 63% (mean 22.7%) and 96.3% (mean 22.6%) of the total concentrations, respectively. There were significant relationships between the amounts of NAHA and endotoxin in the total amount and in the size fraction >1.8 μm but not in the smaller fractions. The results demonstrate significant amounts of fungal cell biomass and endotoxin in particles <1.0 μm. Homes with reported mold damage had a lower concentration of NAHA in particles <1.0 μm than homes without mold damage. To assess airborne exposure for diagnostic and preventive purposes, measurement techniques that include this fraction should be considered.
真菌暴露可能会引起呼吸道症状。致病因子是真菌细胞壁中的化合物。空气中的微生物碎片可能存在，但无法使用常规孢子计数或活生物体测定来测量。本研究评估了来自家庭空气样本中不同粒径分数的真菌细胞生物量和内毒素的比例。使用旋风采样器从 15 个家庭中采集空气样本，收集三个空气动力学粒径分数的颗粒：<1.0、1.0-1.8 和>1.8μm。N-乙酰氨基葡萄糖苷酶（NAHA）被确定为真菌细胞生物量的标志物。使用鲎变形细胞溶解物方法测定内毒素。<1.0μm 粒径范围内的 NAHA 和内毒素分别占总浓度的高达 63%（平均值 22.7%）和 96.3%（平均值 22.6%）。NAHA 和内毒素的含量与总含量和>1.8μm 粒径范围内的含量之间存在显著关系，但在较小的粒径范围内没有关系。结果表明，<1.0μm 的颗粒中存在大量的真菌细胞生物量和内毒素。有报道称存在霉菌损害的家庭中，<1.0μm 的颗粒中的 NAHA 浓度低于没有霉菌损害的家庭。为了出于诊断和预防目的评估空气中的暴露，应考虑包括此部分的测量技术。
