| 摘要: | 國內有許多金屬加工的產業，此種產業製程包括研磨、切削等，機台運轉過程中會因高轉速而產生熱能，因而需大量使用金屬加工液作為冷卻與潤滑，並可帶走接觸面的金屬碎屑、消除接觸面所產生的熱能。由於金屬加工液中富含有機質，易導致機台及油槽內細菌滋生。機台運轉時，也會產生油霧滴，若使用工程控制，如機台護圍、局部排氣裝置或維持場內良好的通風模式，則可避免富含細菌生物氣膠之液滴逸散到作業場所空氣中，進而危害勞工健康。
本研究為瞭解使用金屬加工液作業場所細菌暴露特性，藉由現場生物氣膠採樣而得知，目前至五間有使用金屬加工液之工廠進行採樣，其中僅工廠A之開放式機台使用礦物油，其機台在使用塑膠遮布時，測得之生物氣膠濃度低於偵測下限，掀開後濃度為1.5×105 CFU/m3。B、C、D及E四間工廠，皆使用半合成金屬加工液，其中工廠B僅設有2台CNC機台，其金屬加工液原液未檢出細菌，加入循環使用後增為2.5×101 ~ 4.7×104 CFU/mL，作業現場細菌生物氣膠濃度為88 ~ 364 CFU/m3。工廠C有9台CNC機台及2台隧道型CNC機台，CNC機台使用中金屬加工液細菌濃度為1.2×101 ~ 3.0×107 CFU/mL，隧道型機台使用中金屬加工液細菌濃度為1.5×102 ~ 1.2×103 CFU/mL，CNC機台作業現場之細菌生物氣膠濃度為32 ~ 1648 CFU/m3，隧道型機台作業現場之細菌生物氣膠濃度為72 ~ 370。工廠D有2台CNC機台及1台開放式機台，CNC機台使用中金屬加工液細菌濃度在5.5×104 ~ 2.7×108 CFU/mL，開放式機台使用中金屬加工液細菌濃度在1.0×101 ~ 7.1×107 CFU/mL，CNC機台作業現場之細菌生物氣膠濃度為1,145至9,525 CFU/m3，開放式機台作業現場之細菌生物氣膠濃度為3.9×105 ~ 3.5×108 CFU/m3。工廠E有3台CNC機台及6台開放式機台，其金屬加工液原液未檢出細菌， CNC機台使用中金屬加工液細菌濃度為5.0×105 ~ 2.3×107 CFU/mL，開放式機台使用中金屬加工液細菌濃度為3.4×106 ~ 9.0×106 CFU/mL，CNC機台作業現場之細菌生物氣膠濃度為165 ~ 375 CFU/m3，開放式機台工作業現場之細菌生1.2x103 ~ 3.6x106 CFU/m3。循環使用中的金屬加工液原樣樣本及細菌生物氣膠樣本所測得之主要菌種大致相符。五間金屬加工廠之戶外細菌濃度在65～1,105 CFU/m3之間，皆低於作業現場測得之濃度，檢測出的優勢菌種則不見得一致。
There are many metal processing industries in Taiwan, including grinding and cutting. Metalworking fluids (MWFs) are pure oils or water-based fluids poured or sprayed onto metals to cool, lubrication and prevent corrosion, and to remove metal scraps during machining operations. When the machines operate with MWFs, the droplets containing bacteria bioaerosols would emit into the air in the workplace. The worker will inhale these bioaerosols and cause some respiratory syndomes or diseases. To decrease the bioaerosols risk for the metalworking fluids workplace, the common way is through installation of industrial ventilation.
This study was to know the characteristics of bioaerosols concentration in metalworking fluids workplaces. We collected the bulk MWFs and bioaerosols by Biosampler and MAS-100 sampler in five factories (named as plant A, B, C, D and E). Only plant A using straight MWFs, the concentration was below the detection limit when using a plastic cloth to cover the worksite. When the cloth was removed, the concentration increased to 1.5x105 CFU/m3. The other four plants (B, C, D and E) used soluble MWFs. In plant B has two CNC machines. The semi-synthetic MWFs should be non bacteria, but the bacteria concentrations in MWFs could be in range from 2.5×101 ~ 4.7×104 CFU/mL after using in circles, bacteria bioaerosols concentrations ranged from 88 ~ 364 CFU/m3. In plant C has nine CNC machines and two tunnel-type CNC machines, the bacteria concentrations in MWFs could be in range from 1.2×101 ~ 3.0×107 CFU/mL in CNC machines, and ranged from 1.5×102 ~ 1.2×103 CFU/mL in tunnel-type machines. Bacteria bioaerosols concentrations in CNC and tunnel-type machines could be ranged from 32 ~ 1,648 CFU/m3 and 72 ~ 370 CFU/m3 . In plant D has two CNC machines and an open-type machine, the bacteria concentrations in MWFs could be in range from 5.5×104 ~ 2.7×108 CFU/mL in CNC machines, and ranged from 1.0×101 ~ 7.1×107 CFU/mL in open-type machine. Bacteria bioaerosols concentrations in CNC and open-type machines could be ranged from 1,145 ~ 9,525 CFU/m3 and 3.9×105 ~ 3.5×108 CFU/m3. In plant E has three CNC machines and six open-type machine, bacteria concentrations in MWFs could be in range from 5.0×105 ~ 2.3×107 CFU/mL CFU/mL in CNC machines, and ranged from 3.4×106 ~ 9.0×106 CFU/mL in open-type machines. Bacteria bioaerosols concentrations in CNC and open-type machines could be ranged from 165 ~ 375 CFU/m3 and 1.2×103 ~ 3.6×106 CFU/m3. The prevanlance taxon of bacteria in MWFs and bioaerosols were similar, but still part of the machines further research is needed. The bacteria concentrations outdoor of five plants were ranged from 65 ~ 1,105 CFU/m3. |
