To investigate the pulmonary function changes of ozone exposure in Corona and Slitter workers exposed to an ozone level ranging from 0.022~0.061 ppm.

Forty-two subjects were exposed for 8hrs to ozone every day. We perfomed pulmonary function testing immediately before and after work and self-administered, portable peak flow meter measurements were self-conducted by the workers over a 5-day (Monday to Friday) period.

Ozone concentrations in the workplace ranging from 0.050~0.061 ppm at Corona and 0.022~0.023 ppm at Slitter in 2006. A small decrement in forced-vital capacity were observed among Corona workers from 93.9% to 91.3% (p=0.012) and also in employment duration below ten years. We found no significant differences in before and after FVC and FEV1 among Slitter workers. All daily (Monday to Friday) peak expiratory flow rates declined in magnitude after two days of ozone exposure, compared with first day exposure.

We concluded that daily ozone exposure in the workplace slightly decreased pulmonary function and that PEFR variability is greatest on the 2nd day of ozone exposure.