Eleven ionic species and fine and coarse particle mass concentrations of fine (PM2.5) and coarse (PM10-2.5) particulate matter were investigated in Kaohsiung, southern Taiwan. The PM2.5 and PM10-2.5 particulate concentrations were 49-64 and 34-37 microg x m(-3), respectively. Fifty-five to 64% of the particulate matter less than 10 microm in aerodynamic diameter (PM10) mass was attributed to the PM2.5. PM2.5 concentrations at Daliao (a rural and industrial complex area) were higher than at Tzuoying (an urban and industrial complex area). Ionic species contributed 45-53% and 42-45% of PM2.5 and PM10, respectively. Potassium ions (K+), sulfate (SO4(2-)), and ammonium (NH4+) were predominant in PM2.5, whereas sodium, calcium, and magnesium ions were foremost in PM10-2.5. Nitrate (NO3-) existed in both the PM2.5 and PM10-2.5. Chloride (Cl-), NO3-, and NH4+ concentrations were higher at night than during the day, and they were easily transferred into the gas phase by photochemical reactions and temperature-induced volatilization. The NH4+/SO4(2-) ratios were 2.6 and 2.5 at Daliao and Tzuoying, respectively, which indicated that both sampling sites were rich in NH4+. Therefore, ammonium nitrate would be present in the area.

Workplace air samples from sintering, cokemaking, and hot and cold forming processes in the integrated iron and steel industry were analyzed to determine their volatile organic compound (VOC) concentration. Sixteen VOC species including three paraffins (cyclohexane, n-hexane, methylcyclohexane), five chlorinated VOC species (trichloroethylene, 1,1,1-trichloroethane, tetrachloroethylene, chlorobenzene, 1,4-dichlorobenzene), and eight aromatics (benzene, ethylbenzene, styrene, toluene, m,p-xylene, o-xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene) were selected to measure their noncancer risk for workers. Concentrations of toluene, xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, dichlorobenzene, and trichloroethylene were high in all four processes. Carbon tetrachloride and tetrachloroethylene concentrations were high in the hot and cold forming processes. The noncancer risk followed the increasing order: cokemaking > sintering > hot forming > cold forming. 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene contributed 44% to 65% and 13% to 20% of noncancer risk, respectively, for the four processes. Benzene accounted for a high portion of the noncancer risk in cokemaking. The hazard index (HI: 17-108) of the average VOC concentrations suggests that health risks can be reduced by improving workplace air quality and protecting workers.