Seoul was blanketed on Thursday by the highest-ever concentration of fine particles this year as toxic haze from China lingered for a third day. The Seoul Metropolitan Government issued the first pollution warning at 4 p.m. as ultrafine particles in the city reached more than 85㎍/㎥ for over two hours.
At 5 p.m., fine particles in Seoul's Gwanak District reached 215㎍/㎥, more than double the 100㎍/㎥ environmental standard. The density was so high that even healthy people were advised against staying outdoors for longer periods.
A high density of fine particles was also measured elsewhere across the country, including Gangwon, North Chungcheong, North Jeolla, and North Gyeongsang provinces.
The severe haze continued as smog that came from Shanghai and Qingdao was mixed with vehicle exhaust fumes and fog here, the National Institute of Environmental Research said.
The air quality will improve a little on Friday but the concentration of fine particles in the Seoul Metropolitan area will stay at a level of 81-120 ㎍/㎥ on average, the institute predicted.
Hong Yoo-duk of the institute said severe smog could continue over the weekend.