China is the largest
coke producer and exporter in the world, and it has been a major concern that large populations of
coke workers are exposed to the associated air pollutants such as volatile organic compounds (VOCs). This study aimed to preliminarily quantify the potential exposure to VOCs emitted from two representative coking plants and assess the potential health risks. Air samples from various stages of coking were collected from the topside of
coke ovens and various plant areas and then analyzed for benzene, toluene, ethylbenzene, and xylene (BTEX). The time-weighted average (TWA) concentrations were used to quantify the
coke oven emission (COE). The TWA concentrations for benzene were 705.6 and 290.4 μg m(-3) in plant A and plant B, respectively, which showed a higher exposure level than those reported in other countries. COE varied on the topside of
coke ovens during charging and pushing processes, from 268.3 to 1197.7 μg m(-3) in plant A and 85.4-489.7 μg m(-3) in plant B. Our results indicate that benzene exposure from the diffusion of tar distillation also exerts significant health risks and thus should also be concerned. Charging and pushing activities accounted for nearly 70 % of benzene dose at the topside, and the benzene exposure risks to the coke oven workers in China were higher than those reported by US EPA. Compared to the reported emission sources, the weight-based ratios of average benzene to toluene, ethylbenzene, and xylene in different COE air samples showed unique characteristic profiles. Based on the B/T ratios from this work and from literatures on several major cities in northern China, it was evident that COE contributes significantly to the severe pollution of VOCs in the air of northern China. Future more rigorous studies are warranted to characterize VOC emission profiles in the stack gas of the coking processes in China.