School of Environmental Science and Engineering, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
Environ Sci Technol. 2013;47(21):12469-76. doi: 10.1021/es4026613. Epub 2013 Oct 16.
The representative waste television recycling process was chosen as the object of this study, including manual dismantling and mechanical separation of printed circuit boards (PCBs) and cathode ray tubes (CRTs) in two independent workshops. During these recycling processes, fine particulate matter and heavy metals will be released into the air to impact the environment and the health of the workers. The mass concentrations of PM2.5 (particles below 2.5 μm diameter) in mechanical and dismantling workshops ranged from 252.6 to 290.8 μg/m(3) and from 112.7 to 169.4 μg/m(3), respectively. The average concentration of PM2.5 around the workshop was 98.5 μg/m(3). Meanwhile, the contents of PM10 (particles below 10 μm diameter) were all below the risk threshold, except that (360.4 μg/m(3)) monitored in the mechanical workshop. In two workshops, Pb (20.46 and 6.935 mg/g) was the most enriched metal in the PM2.5 samples, while in PM10, the concentration of Cu (27.76 and 31.80 mg/g) was the largest. The concentration of Cd was the least in both PM10 and PM2.5. Health risk assessment showed that the total hazard indexes for non-carcinogenic metal in PM2.5 monitored in mechanical and dismantling workshops and in the southeast of the workshops were 7.61, 3.01, and 1.57, respectively, all above the safety level. Furthermore, Pb (7.28 and 3.01) might possibly have a non-carcinogenic effect on the workers in two workshops, and the sequence of the hazard quotient (HQ) through the three exposure ways was ingestion > dermal contact > inhalation. The lifetime cancer risk of four targeted metals was Cr > Ni > Pb > Cd, which could be proven in all monitoring samples. This study aims to provide a large amount of valid data for the State Environmental Protection Department to develop relevant environmental standards and for companies to improve the waste television recycling system to be more efficiently and environmentally friendly.
本研究选择具有代表性的废电视机回收工艺为研究对象,包括在两个独立的车间中进行印刷电路板(PCB)和阴极射线管(CRT)的人工拆卸和机械分离。在这些回收过程中,细颗粒物和重金属会释放到空气中,从而影响环境和工人的健康。机械车间和拆卸车间的 PM2.5(直径小于 2.5μm 的颗粒物)质量浓度范围分别为 252.6 至 290.8μg/m3 和 112.7 至 169.4μg/m3,车间周围 PM2.5 的平均浓度为 98.5μg/m3。同时,除机械车间监测到的 PM10(直径小于 10μm 的颗粒物)含量为 360.4μg/m3 外,其余含量均低于风险阈值。在两个车间中,Pb(20.46 和 6.935mg/g)是 PM2.5 样品中最富集的金属,而在 PM10 中,Cu(27.76 和 31.80mg/g)的浓度最大。Cd 在 PM10 和 PM2.5 中的浓度均最小。健康风险评估表明,在机械车间和拆卸车间以及车间东南方向监测的 PM2.5 中非致癌金属的总危害指数分别为 7.61、3.01 和 1.57,均超过安全水平。此外,Pb(7.28 和 3.01)可能对两个车间的工人有非致癌影响,三种暴露途径的危害商(HQ)顺序为摄食>皮肤接触>吸入。在所有监测样本中,四种目标金属的终生癌症风险均为 Cr>Ni>Pb>Cd。本研究旨在为国家环境保护部门制定相关环境标准以及企业改进废电视机回收系统提供大量有效数据,使其更高效、更环保。