BACKGROUND: PM10(Particulate matter with a diameter < 10micrometer), which is characterized by different environmental conditions, is a complex mixture of organic and inorganic compounds. The Asian dust event caused by meteorological phenomena can also produce unique particulate matter in affected areas. This study investigated the cytokine produced by A549 epithelial cells exposed to particles collected during both the Asian dust pfenomenon and ambient air particles in a non-dusty period. METHOD: Air samples were collected using a high volume air sampler(Sibata Model HV500F) with an air flow at 500l/min for at least 6 hours. The cytokine messenger RNA(mRNA) was measured using a reverse transcriptase polymerase chain reaction(RT-PCR). The A549 cells were exposed to 10 to 500microgram/microliter of a suspension containing PM10 for 24 hours. Each was compared with those in the non-exposed control cells. RESULT: The mRNA levels of interleukin(IL)-1alpha, IL-Ibeta , IL-8, and the granulocyte macrophage colony stimulating factor(GM-CSF) increased after veing exposed to PM10 in the ambient air particles, compared with those in the non-exposed control cells. The increase in IL-1alpha and IL-8 were dose dependent at a PM10 concentration between 100microgram/microliter and 500microgram/microliter. The mRNA level of IL-8 in the A549 epithelial cells was higher during the in the Asian dust period(500microgram/microliter) than during the non dust period. CONCLUSION: A549 cells exposed to the PM10 collected during the Asian dust period produce more proinflammatory cytokine than during non-dusty period. This cytokine enhances the local inflammatory response in the airways and can also contribute to the systemic component of this inflammatory process.