在室內空氣污染物中,甲醛為主要污染物之一。甲醛對人體具有急性危害,同時也被世界衛生組織所屬的國際癌症研究所 (Internation Agency for Research of cancer, IARC ) 歸類為人類具致癌性物質。臺灣地區因裝修習慣及氣候 (高溫、高濕)等因素,造成室內甲醛濃度過高之現象。國內外已有相關文獻證實幾丁聚醣塗佈於 (乾式) 建材表面,具有分解甲醛之效果。故本研究使用幾丁聚醣搭配空調濾網,進行氣狀污染物-甲醛去除研究。 本實驗所組合使用JIS A1901小尺寸環控系統及風管環境控制箱,並利用聚丙烯纖維濾網進行噴塗不同量之幾丁聚醣抑制劑 (2.6 mg/m2、5.3 mg/m2、8.0 mg/m2 ),甲醛移除效能測試實驗,探討不同幾丁聚醣噴塗比例時,甲醛濃度抑制率與幾丁聚醣添加量關係,計算進料甲醛污染物濃度去除量及吸收率,並計算甲醛之健康風險評估。本研究之分析結果可歸納以下結論: 1. 噴塗1.56 mg/m2 幾丁聚醣於濾網上,前3小時去除甲醛濃度可降至最低點0.152 ppm (0.230 ~ 0.152 ppm);14小時後甲醛濃度會上升至濃度0.962 ppm (0.230 ~ 0.962 ppm)。不同比例之幾丁聚醣噴塗量結果顯示,噴塗1.56 mg/m2幾丁聚醣於濾網其24小時之甲醛平均濃度為0.84 ppm;噴塗含量0.4 g幾丁聚醣於濾網,第16小時甲醛濃度達0.487 ppm (0.487 ~ 1.458 ppm ),而第16 ~ 24小時濃度趨近於穩定,約0.642 ppm;噴塗含量3.44 mg/m2幾丁聚醣於濾網,第15小時達到穩態,濃度值約0.240 ppm,則24小時平均濃度分為0.241 ppm。 2.本研究之24小時幾丁聚醣濾網之甲醛抑制率24小時顯示,含幾丁聚醣濾網之甲醛平均濃度與未含幾丁聚醣濾網之甲醛平均濃度之比值可得知,幾丁聚醣濾網添加量分別為1.56 mg/m2、3.44 mg/m2、5.60 mg/m2 時,幾丁聚醣對甲醛之抑制效率,分別為59.5%、70.1%、及89.0%。 3.24小時之幾丁聚醣對甲醛吸收量結果,幾丁聚醣濾網噴塗量分別為1.56 mg/m2、3.44 mg/m2、5.60 mg/m2時,吸收量分別為0.167 mg、0.204 mg、0.271 mg。 4.甲醛健康風險評估之假設情境為室內裝修結束後,推算未使用幾丁聚醣濾網及使用噴塗幾丁聚醣濾網於空調系統中,人體所受到的健康致癌風險值。未噴塗幾丁聚醣濾網抑制劑之風險值,分別為噴塗1.56 mg/m2、3.44 mg/m2、5.60 mg/m2幾丁聚醣抑制劑的2.49倍、2.65倍、7.07倍。此結果可得知,隨著幾丁聚醣濾網噴塗量增加,室內甲醛濃度會隨之下降,同時亦降低甲醛之致癌風險值。
For indoor air quality, formaldehyde is one of the main pollutants. It not only has acute hazard to human healthy, but also is classified as a cancer-causing substance by International Agency for Research of Cancer. Due to indoor remodeling, decoration, climate (high humidity and temperature), and other factors, it causes the high concentration of formaldehyde. Many studies have confirmed that Chitosan coated on the surface of building materials (dry-type) can decompose formaldehyde effectively. Therefore, this study is to use chitosan sprayed on the filters of air-conditioning system in order to remove formaldehyde. JISA 1901 small chamber testing system and air-conditioned chamber are used in this study. The filter is sprayed with different dosages of Chitosan (1.56 mg/m2, 3.44 mg/m2, and 5.60 mg/m2 ) to test formaldehyde removal and find the relationship between inhibition of formaldehyde concentration and dosages of Chitosan. Removal rate and absorption of formaldehyde need to be calculated for the health risk assessment. After twenty-four hours testing, the results showed the averaged concentration of formaldehyde is 0.487ppm, 0.642 ppm, and 0.241 ppm with Chitosan dosage of 1.56 mg/m2, 3.44 mg/m2, 5.60 mg/m2 , respectively. The averaged inhibition of formaldehyde concentration is 59.5%, 70.1% and 89.0%; the averaged absorption of Chitosan on Formaldehyde is 0.167 mg, 0.204 mg and 0.271 mg to the Chitosan dosage of 1.56 mg/m2, 3.44 mg/m2, 5.60 mg/m2, respectively. The risk characterization without spaying Chitosan are 2.94, 2.65 and 7.07 times higher than spraying 1.56 mg/m2, 3.44 mg/m2, and 5.60 mg/m2 of Chitosan filter. As a result, increasing the amount of Chitosan can decrease the indoor Formaldehyde concentration and the cancer-causing risk.