居家環境中室外及牆面上真菌對室內空氣真菌濃度之影響

Abstract

摘要 目的：比較室外空氣真菌濃度及室內表面真菌生長情形對於室內空氣 真菌濃度的貢獻。 方法：於2003年12月至2005年12月所收集到1000多對媽媽-小孩配對樣本的研究世代中選取28位小孩患有過敏性疾病如：氣喘、過敏性鼻炎及異位性皮膚炎及14位未患有以上疾病的小孩於2007年6~9月間進行居家環境採樣。採樣期間小孩大約為2歲，採樣地點分布於全台7縣市：台北縣、新竹市、雲林縣、嘉義縣、台南市、高雄市及台東市。隔年，由另一個呼吸道研究族群中選取8位就讀國中小的孩童進行居家環境採樣。空氣真菌樣本使用安德森單階微生物衝擊器採樣，採樣的地點為室外：主要住宅之外部、客廳及小孩子房間中心處約100公分高的位置以接近孩童呼吸帶。表面真菌的樣本則取至於牆面、天花板及傢俱表面等有任何可見表面真菌存在之處。使用鏡檢辨識真菌的種類，空氣中及表面皆觀察到的真菌總類包含了Cladosporium, Penicillium, Aspergillus, Geotrichuum, Yeast,及Verticillium. 結果：室外空氣真菌濃度對室內空氣真菌濃度的貢獻性很高，R2為0.31，若依菌種分別分析Verticillium、Geotrichuum、Penicillium、Cladosporium、Yeast及Aspergillus的R2值分別為0.99, 0.67, 0.61, 0.55, 0.51和0.36。除了Geotrichuum大多數的表面真菌對於室內空氣真菌的濃度均未達統計上顯著意義，其P值為0.0055。將室外空氣濃度與表面真菌濃度均放入模式後可發現，室外空氣真菌濃度對室內空氣真菌濃度均有貢獻，表面真菌則僅有Aspergillus和Geotrichuum對室內空氣真菌濃度達統計上顯著意義，其P值分別為0.0013及0.0254。我們同樣發現在校正了室外空氣真菌濃度及其他環境因子包括溫度、相對溼度、風速及二氧化碳濃度後，Aspergillus和Geotrichuum 對室內空氣真菌濃度的貢獻仍達統計上的顯著意義，其P值分別為0.0025及0.0437。而表面真菌的牆面比值與面積比值可用來表示室內環境中表面真菌的濃度指標。在校正了室外真菌孢子的影響後，表面真菌Aspergillus的表面真菌的牆面比值與面積比值仍與室內空氣真菌Aspergillus相關，P值分別為0.0095及0.0069。 結論：研究中發現室內空氣真菌的來源大多為室外的真菌孢子，而表面真菌Aspergillus和Geotrichuum同樣對於室內空氣真菌濃度有所貢獻。

Abstract OBJECTIVE: Indoor molds, especially those seen on wall surfaces, have been associated with occurrence of atopic diseases in children. The objective of this study is to determine whether wall surface fungus contributed to indoor airborne fungus. METHOD: From a birth cohort of 1000 mother-infant pairs followed from the third trimester between December 2003 to December 2005, we selected 28 residents of children with asthma, allergic rhinitis, or atopic dermatitis, and 14 residents of children with none of the above diseases for indoor environment evaluation, from Taipei County, Hsinchu City, Yunlin County, Chiayi County, Tainan City, Kaohsiung City, and Taitung City. In the following year, we selected 8 residents from the other respiratory health study population in Taipei County. Living room and child bedroom air samples were collected using Andersen Single Stage Microbial Sampler, with malt extract agar plates for fungal spores. Outdoor samples were taken from outside of the main gate. In addition, surface samples were taken from vertical wall, floor and ceiling tile with obvious mould. The identified microbial genera include Cladosporium, Penicillium, Aspergillus, Geotrichuum, Yeast, and Verticillium. RESULT: The number of indoor airborne fungus was highly related to outdoor fungus, with an R-square of 0.31. R-squares for Verticillium, Geotrichuum, Penicillium, Cladosporium, Yeast, and Aspergillus were 0.99, 0.67, 0.61, 0.55, 0.51, and 0.36 respectively. Wall growth of Aspergillus (p=0.0013) and Geotrichuum (p=0.0254) contributed significantly to the indoor fungus adjusted for outdoor airborne fungus concentrations. Such contributions were not changed after further adjusting for temperature, relative humidity, wind velocity, and CO2 concentration. CONCLUSION: For indoor fungal spores, total, Cladosporium, Penicillium, Aspergillus, Geotrichuum, Yeast, and Verticillium were all contributed by outdoor spores. However, wall growth of Aspergillus and Geotrichuum contributed significantly to the indoor fungal spores. Keyword: airborne fungus, surface fungus.