A new South Korean government survey shows China is responsible for 30 to 50 percent of ultra fine dust blanketing the country. 

The finding was released on Wednesday by a pan-government task force consisting of officials from related ministries. 

The survey tracked ultra fine dust concentrations over the past five years and estimated 30 percent of them came from China when levels were 20 micrograms per cubic meter or less. 

The figure rose to 50 percent when the particles’ concentration was 50 micrograms per cubic meter or higher. 

Launched in September 2017, the task force plans to inject a total of 49-point-six billion won by next year into research on fine dust problems. 

It plans to fly a research airplane this month to track travel routes of fine dust over the West Sea.