Bogdanovic J, de Pater A J, Doekes G, Wouters I M, Heederik D J J
Institute for Risk Assessment Sciences, Utrecht University, The Netherlands;
Ann Occup Hyg. 2006 Mar;50(2):131-6. doi: 10.1093/annhyg/mei050. Epub 2005 Sep 7.
Exposure to airborne wheat allergen is a well-known cause of bakers' allergy and asthma. Airborne wheat allergen can be measured by enzyme immunoassays (EIAs) in extracts of inhalable dust samples, but only limited knowledge is available on the size distribution of wheat allergen-carrying particles. Recently, a new sampling medium, porous polyurethane foam, has been introduced for the size-selective sampling of airborne dust in various occupational settings. We investigated the applicability of these foams for size-selective wheat allergen measurements.
Personal and stationary measurements were performed in a flour mill, using respirable and thoracic foams inserted into the conventional IOM inhalable sampler, together with PTFE (Teflon) filters. Foams and filters were eluted and wheat allergen levels determined by human IgG4 inhibition EIA.
Wheat allergen levels could be determined in both filter and foam eluates. Inhalable dust levels from filters and foams ranged from 1.4 to 53 mg m(-3), and wheat allergen levels from 15 to 580 microg m(-3). The allergen was mainly borne on particles with D(ae) (particle aerodynamic diameter) > 10 microm and particles with 4 microm < D(ae) < or = 10 microm, accounting for 54.5-77.5% and 18.9-43.2% of the total allergen yield, respectively. Less than 4% of airborne wheat allergen was carried by particles smaller than 4 mum (respirable fraction).
Measurement of wheat allergen in dust fractions trapped in respirable and thoracic foams is technically feasible. Both wheat flour dust and wheat allergen are mainly concentrated in larger particle-size fractions (extrathoracic and tracheobronchial).
接触空气中的小麦过敏原是面包师过敏和哮喘的一个众所周知的原因。空气中的小麦过敏原可通过酶免疫测定法（EIA）在可吸入粉尘样本提取物中进行测量，但关于携带小麦过敏原的颗粒大小分布的知识有限。最近，一种新的采样介质——多孔聚氨酯泡沫，已被引入用于各种职业环境中空气传播粉尘的尺寸选择性采样。我们研究了这些泡沫在尺寸选择性小麦过敏原测量中的适用性。
在一家面粉厂进行个人和固定测量，将可吸入和胸腔泡沫插入传统的IOM可吸入采样器中，同时使用聚四氟乙烯（PTFE）过滤器。对泡沫和过滤器进行洗脱，并通过人IgG4抑制EIA测定小麦过敏原水平。
在过滤器和泡沫洗脱液中均可测定小麦过敏原水平。过滤器和泡沫的可吸入粉尘水平范围为1.4至53 mg m(-3)，小麦过敏原水平范围为15至580 μg m(-3)。过敏原主要存在于空气动力学直径（D(ae)）>10微米的颗粒和4微米<D(ae)≤10微米的颗粒上，分别占总过敏原产量的54.5 - 77.5%和18.9 - 43.2%。小于4%的空气中小麦过敏原由小于4微米的颗粒（可吸入部分）携带。
在可吸入和胸腔泡沫中捕获的粉尘部分中测量小麦过敏原在技术上是可行的。小麦面粉粉尘和小麦过敏原都主要集中在较大粒径部分（胸外和气管支气管）。
