牙體技術師作業場所重金屬與生物氣膠特性評估

本研究選擇3間牙體技術所的研磨作業區進行環境中採樣，分析探討環境中生物氣膠的分佈與特性及牙體技術師在研磨作業時產生化學性粉塵其濃度、粒徑與重金屬成份等分析。微粒採樣方式選擇Fidas®Frog以及DustTrak™ DRX 8533氣膠監測儀在研磨作業區進行6小時採樣，並分析PM1、PM2.5、可吸入微粒、PM10及總懸浮微粒(total suspended particulates, TSP)粒徑分佈與質量濃度等讀數。粉塵採樣選用旋風分離器等設備進行6小時採樣，將濾紙與集塵袋樣本送至實驗室進行重金屬成份分析。並結合集塵袋粉塵數據，推估無集塵設備的暴露狀況。另外使用安德森六階衝擊器收集含有真菌的氣膠，分別於工作初期及工作一段時間後採樣10分鐘，並培養分析菌種類型與數量。結果顯示，不同牙體技術所之可呼吸性粉塵量佔總粉塵量約 34.2–64.1%，顯示環境中滯留的粉塵中約有半數屬於可深入肺部的細懸浮微粒。粒徑分佈分析亦可發現，3間牙體技術所皆以 0.2–0.3 µm 的微粒為主要釋放區間，並呈現一致的濃度隨粒徑遞減之趨勢。在各場所比較上，牙體技術所 F1 的粉塵濃度與變異性均屬中等或偏低，顯示其暴露風險相對穩定，為管理較佳之作業環境。相對地，牙體技術所 F2 與 F3 在不同次採樣間的 CV 值差異明顯，顯示其粉塵產生量波動劇烈，可能與不連續或集中式的作業行為有關，亦突顯該兩場所之暴露環境不穩定性。此外在粉塵重金屬分析可以發現，金屬以鉻、鎳、銅為大宗，另外依照不同公司之製程與假牙母材的差異會使鋯、鋅等成份佔比不同。吸入性非致癌風險度與吸入性致癌風險度分析結果則顯現在各牙體技術所研磨工作區工作的人員皆有金屬鉻導致致癌的風險，尤其工作年資越長者，風險即越高。集塵袋的成分及有害物容許濃度計算分析結果可看出局部排氣設備之使用的確能降低環境中有害物的殘留，降低工作人員健康危害的風險。最後，真菌採樣分析結果顯示不論在哪間牙體技術所，其採樣優勢菌種多數為Cladosporium spp.、Penicillium spp.、Trichophyton spp.及Aspergillus spp.，占整體分離菌種的78.0-99.4%。本研究中揭示了牙體技術所作業環境中粉塵及真菌分佈的情況，強調環境通風及局部排氣設備在控制粉塵及生物氣膠濃度中的重要性，以保障牙體技術師的工作安全和健康。

This study selected three dental technician laboratory to conduct environmental sampling in grinding operation areas. The objective was to analyze the distribution and characteristics of bioaerosols, as well as the concentration, particle size, and metal composition of chemical dust generated by dental technicians during grinding processes.Particulate sampling was conducted using Fidas® Frog and DustTrak™ DRX 8533 aerosol monitor, and an Andersen six-stage impactor in the grinding work areas. Readings were analyzed for PM₁, PM₂.₅, respirable dust, PM₁₀, and total suspended particulates (TSP) in terms of mass concentrations and size distributions.Dust sampling was carried out using cyclone separators, with collected samples (filter papers and dust bags) analyzed in the laboratory for metal composition content. Based on the dust bag data, exposure levels in the absence of local exhaust ventilation (LEV) systems were estimated. Additionally, a six-stage Andersen impactor was used to collect fungal bioaerosols, with 10-minute samples taken at the beginning and after a period of operation, followed by cultivation and identification of fungal species and quantities.The results indicated that respirable dust accounted for 34.2% to 64.1% of the total dust in the sampled dental technician laboratories. Particle size distribution analysis showed that all three laboratories predominantly released particles within the 0.2–0.3 µm range, following a consistent pattern of decreasing concentrations with increasing particle size. Further analysis of dust exposure revealed that laboratories F2 and F3 demonstrated unstable coefficients of variation (CV) across different sampling sessions, suggesting considerable fluctuations in dust generation, likely associated with intermittent or intensive work activities. In contrast, laboratory F1 exhibited moderate to low dust concentrations and variability, reflecting a relatively stable exposure profile and indicating better workplace management practices.Metal composition analysis revealed chromium, nickel, and copper as predominant elements, with zirconium and zinc levels varying depending on each laboratory’s processes and prosthetic materials. Inhalation risk assessment indicated that workers in all laboratories are at carcinogenic risk from chromium exposure, with higher risks observed in more experienced personnel. Analysis of dust bag contents and permissible exposure limits demonstrated that the use of LEV systems effectively reduces airborne hazardous substances and mitigates occupational health risks. Lastly, fungal sampling showed that dominant fungal genera—Cladosporium spp., Penicillium spp., Trichophyton spp., and Aspergillus spp.—accounted for 78.0%to99.4%of isolated strains across all laboratories.This study highlights the distribution of dust and fungal bioaerosols in dental laboratory environments and underscores the critical role of environmental ventilation and local exhaust ventilation systems in controlling particulate and bioaerosol concentrations, thereby safeguarding the occupational health and safety of dental technicians.