高雄市國小學童家戶空氣中內毒素濃度

Airborne Endotoxin in School Children’s Houses in Kaohsiung City

顏珮珺(Pei-Chun Yen)

指導教授 ： 陳培詩

高雄醫學大學/健康科學院/職業安全衛生研究所/碩士(2012年)

摘要

近年來，人們待在室內的時間普遍變長，室內空氣品質愈來愈受到重視；而孩童更是被視為是對空氣汙染物的敏感族群。本研究地點高雄市位在的高屏地區為全台灣空氣品質最不佳的，因此需要針對高雄地區之家戶室內空氣汙染情形與學童的健康做進一步的探討。
內毒素是革蘭氏陰性菌細胞外膜上的成分，它具有很高的耐熱性且普遍存在於環境當中，並且對於人體的免疫系統具有強悍及非特異性刺激的特性，根據文獻發現暴露於高內毒素濃度的環境當中會導致病態大樓症候群等負面的健康效應的發生。
在許多研究中發現採樣樣本仍以室內的灰塵居多，此採樣方法並不能準確的代表人體吸入的暴露狀況。因此本研究的目的為（1）評估高雄市家戶空氣中內毒素濃度（2）比較敏感孩童與非敏感孩童之家戶空氣中內毒素之差異（3）了解內毒素對於孩童肺功能之間的關係（4）探討家戶其它生物性汙染物與內毒素之相關性在此研究中，家戶內毒素空氣樣本的採樣在2010/04/06至2012/02/22間進行，根據問卷調查出有氣喘以及有過敏的孩童，於2010/04/06至2010/10/06進行第一波的採樣，針對對象為氣喘與非氣喘的60位配對孩童之家戶；另外於2011/04/13至2012/02/22進行第二波的採樣，針對對象為過敏與非過敏的60位配對孩童之家戶。採樣地點為孩童臥室以及孩童家戶客廳，我們利用37mm、孔徑為1.0μm的鐵氟龍濾紙，以流速20 L/min進行24小時空氣的採樣。並量測孩童的肺功能狀況(HI-801, CHEST, JAPAN)以及量測其他室內空氣汙染物，如真菌（Malt extract agar, MEA)、細菌（Tryptic soy agar, TSA)。而後續更進一步針對孩童檢驗血液過敏原以確定孩童患有過敏的狀況。
研究結果發現，不管是以問卷或是以血液分類，氣喘/過敏與非氣喘/非過敏家戶空氣中內毒素濃度並沒有顯著的差異。另外也發現氣喘孩童的肺功能顯著的優於非氣喘孩童的肺功能；而在過敏的部分，以問卷分類的結果顯示過敏與非過敏的孩童肺功能沒有統計上顯著的差異，但以血液分類的結果顯示過敏孩童的肺功能顯著的優於非過敏孩童的肺功能。同時，若以四分位濃度為界線，切成高暴露與低暴露組，敏感與非敏感族群臥室的內毒素濃度高於Q3濃度比低於Q1濃度得到氣喘或過敏的勝算比為3.825。
而本研究之結論認為，家戶空氣中內毒素濃度愈高可能會使孩童得到氣喘或過敏的機率提高，但氣喘或過敏孩童的肺功能並不一定較差，對肺功能可能是一保護作用。

關鍵字

氣喘 ； 過敏 ； 孩童肺功能 ； 空氣內毒素 ； 真菌 ； 細菌 ； 室內空氣品質 ； 跳床

並列摘要

Recently, people spend much more time in indoor environments. Children are recognised as particularly sensitive population to air pollution because their lung structure and immune system is not fully developed, especially, the children who have asthma or allergy.
Endotoxin is a term for the toxin characteristic of the outer membrane of gram-negative bacteria. Endotoxin is heat-stable, and ubiquitous in the environment. It is also recognized as a powerful and nonspecific stimulant to the immune system, endotoxin can induce negative health responses on respiratory symptoms, such as severe asthma attacks and sick building syndrome symptoms.
In many studies related to health effects of endotoxin, samples are usually only collected from a reservoir such as settled house dust. This method may inaccurately represent the quantity of allergens and pyrogens entering the lungs. So the purposes of this study are 1) to evaluate airborne endotoxin in schoolchildren’s house in Kaohsiung City; 2) to compare the airborne concentration of endotoxin with asthma/allergy and non-asthma/non-allergy in children’s houses; 3) to investigate the relation between endotoxin and asthma /allergy and lung function among school-age children; 4) to discuss relation between endotoxin and other bioaerosols.
In this study, there are two sampling period of endotoxin, 2010/04/06~2010/10/06 and 2011/04/13~2012/02/22. We collected the bedroom and living room’s air samples for endotoxin analysis on 37-mm Teflon filters with 1-μm pore size at a flow-rate of 20 L/min for 24 hrs. We measured children’s lung function (HI-801, CHEST, JAPAN) and measured other bioaerosols, such as fungal and bacterial bioaerosols by MAS-100 (MERCK USA). Tryptic soy agar (TSA) and Malt extract agar (MEA) was used for cultivated of bacteria and fungus, respectively. Furthermore, according to the children’s blood sample to define allergy or not.
We found the endotoxin concentration have no significantly difference between the children with asthma/allergy and children without asthma/allergy. We also found that asthmatic/allergic children’s lung function were better than non-asthmatic/non-allergic children. For the airborne endotoxin in all bedrooms, the first and third quartile endotoxin level in all bedrooms were 0.31 EU/m3 and 1.97 EU/m3. When comparing with 0.31 EU/m3 (Q1), the endotoxin concentration higher than 1.97 EU/m3 (Q3) was associated with a significant prevalance in asthma or allergy with the OR (95% CI) of 3.825(1.221-11.981).
The conclusion of this study is that the higher endotoxin concentration in the house may cause children to get the asthma or allergy, but not necessarily poor lung function of asthmatic or allergic children, the endotoxin may be a protective effect on children’s lung function.

並列關鍵字

asthma ； allergy ； children’s lung function ； air endotoxin ； bacteria ； fungi ； indoor air quality ； jumping on the bed

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