廢塑膠回收處理作業勞工有害物暴露評估研究

A Study on the Assessment of Hazardous Exposure to Workers in Waste Plastic Recycling Operations

隨著我國推動產業綠色轉型，政策鼓勵廢塑膠回收再利用。然而，回收處理過程可能產生有毒物質，對作業勞工健康構成威脅。本研究透過作業環境監測與勞工尿液分析，探討有害物質暴露情形，並以氧化壓力指標（8-hydroxy-2-deoxyguanosine, 8-OHdG）評估暴露與健康關聯。結果顯示，造粒區暴露風險較高，惟因多數設備為密閉式，三氯乙烯、甲苯、乙苯、苯乙烯與氯乙烯濃度均未高於其他區域，且低於容許暴露標準。尿液中，現場作業員之甲苯代謝物（Hippuric acid, HA）、乙苯與苯乙烯代謝物（Mandelic acid, MA）濃度高於辦公室員工，且下班後HA、MA與8-OHdG平均值具統計差異。即使環境中苯乙烯濃度極低，仍可自尿液觀察MA變化，顯示其可作為苯乙烯暴露之生物指標。此外，粉碎、造粒與清洗區噪音量測均高於容許標準，具潛在聽力損害風險，此現象值得重視及長期關注勞工聽力健康。目前國內此產業多限於回收、清洗與物理破壞，較少涉及高溫熔融製程。建議未來針對具加熱熔融造粒程序之製造業與紡織業，進行更深入暴露調查與生物監測，以全面掌握健康風險。

With the national push for green industrial transformation, policies have promoted the recycling and reuse of waste plastics. However, the recycling process may generate toxic substances, posing potential health risks to workers. This study assessed occupational exposure through environmental monitoring and urinary biomonitoring, including the oxidative stress marker 8-hydroxy-2-deoxyguanosine (8-OHdG), to evaluate associations between exposure and health effects.
Results indicated higher exposure risks in the pelletizing area. However, due to predominantly closed systems, concentrations of trichloroethylene, toluene, ethylbenzene, styrene, and vinyl chloride were not elevated compared to other areas and remained below permissible exposure limits. Urinary analysis revealed that frontline workers had higher levels of toluene (hippuric acid, HA), ethylbenzene and styrene (mandelic acid, MA) metabolites than office staff. Post-shift HA, MA, and 8-OHdG levels were significantly elevated in frontline workers.
Notably, MA was detectable in urine despite low environmental styrene levels, suggesting its utility as a biomarker for styrene exposure. In addition, noise measurements in shredding, pelletizing, and washing areas exceeded regulatory limits, indicating potential risk for hearing loss and warranting ongoing monitoring.
Currently, most recycling operations focus on collection, washing, and mechanical processing, with limited involvement in high-temperature melting. Further investigations targeting industries engaged in thermal pelletizing processes, such as plastics manufacturing and textiles, are recommended to comprehensively assess exposure and health risks in the circular plastics economy.