Representatives from South Korea, China, Japan and Mongolia have gathered in Seoul to address concerns of ultrafine dust.
 
Roughly 300 South Korean and foreign atmosphere experts and government officials met in Seoul on Thursday at the Northeast Asian International Seminar on Air Quality Improvement. There they discussed reducing the harm on human health by ultrafine dust.
  
While the seminar was under way, an exhibition and market for products to improve the quality of air were also held.