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The introduction of lasers as a cutting tool has become an important step in achieving further cost reductions in the multi-functional optical film industry. However, the fumes produced during laser cutting causes an annoying and often unbearable odor in the working environment. To date, little research has been reported in terms of the worker exposure assessment and odorous substances generated in the process of cutting plastics with lasers. This study firstly investigated the worker exposure assessment and the protection efficiency of the carbonyls and phenols when a laser is used to cut polycarbonate (PC) and polyethylene terephthalate (PET), the primary base materials used in optical film industry. Results indicate that the concentrations of these substances increased with the power of the laser. Due to differences in the monomer structures of these materials, a 240 W laser produced a high concentration of phenols (1.56 mg m . However, the result of the masks studies could only reduce concentrations to between 1.88 mg m -3 and 2.2 mg m -3 , which barely meet the related regulatory standards. In contrast, the installation of local ventilation alone can effectively remove as much as 99% of the gaseous substances produced in the laser cutting of plastics.

In the last five years laser cutting has been identified as one of the solutions for converting and shaping the plastic films used in the Thin Film Transistor Liquid Crystal Display (TFT-LCD) industry due to its positive effects on cost management. However, there has been quite limited information available with regard to the hazards of the air pollutants released during the laser cutting process, and in particular in relation to the real operations that occur in a factory. This is the first study that aims to assess the Endocrine Disruptors (EDs) and Particulate Matter (PM) emitted during the laser cutting process. Phthalate Esters (PAEs) and Polycyclic Aromatic Hydrocarbons (PAHs) are the representative EDs in this research. The results indicate that the power of the laser and type of plastic significantly affect the composition of air pollutants. Di(2-ethylhexyl) phthalate (DEHP) of PAEs was identified in the Laser Generated Air Contaminants (LGACs) from both Polycarbonate (PC) and Polyethylene Terephthalate (PET) films. DEHP was detected in the gas-phase LGACs of PC and PET at low, medium and high power (80 W, 160 W, 240 W), but not detected in the particle-phase LGACs of PC and PET, except when the laser was operated at a low power setting. With the laser power increased, the concentrations of PM and PAHs also increased. This research found that during laser cutting PC released more DEHP than PET, but PET released more PAHs than PC.

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