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High-flying ideas?
A camera-equipped drone flies around the outskirts of Seoul, South Korea, hovering near an industrial plant and capturing video of pollutants. Below, on the crowded, litter-covered streets, residents wear white and black masks that cover their noses and mouths. A gray haze hangs ∈ the sky.
The unmanned aerial vehicle, or UAV, is part of a pilot program by South Korea’s Ministry of Environment. Tasked with inspecting factory emissions ∈ the capital’s greater metropolitan area, it’s the latest ∈a series of tech solutions aimed at solving Seoul’s dust dilemma. In fact, the fine dust has South Koreans so concerned they’ve cited it as their No. 1 stressor ∈ life – more distressing than the country’s economic stagnation, its rapidly aging population and even North Korea’s erratic dictator and nuclear weapons program.
Their worries are well-founded. The World Health Organization (WHO) advises exposure to fine dust, or PM10, of no more than a daily average of 50 micrograms per cubic meter, and to ultra-fine dust, or PM2.5, of no more than 25. At one point ∈2017, Seoul’s PM10 hit 179. In late March 2018, Seoul’s PM2.5 soared to over 100. PM2.5 is of greatest concern. So small it can get lodged into the lungs and penetrate the lining to enter the bloodstream, PM2.5 is comprised of black carbon, nitrates, ammonia and other harmful compounds linked to respiratory diseases and cancer. The WHO has classified fine and ultra-fine dust as carcinogenic since 2013.
Developed by the government-run National Institute of Environmental Research, the drone is the first of what the environment ministry intends to be a fleet deployed nationwide. Some South Korean tech companies, too, are stepping ∈ with their own innovations. Although much of the new tech appears promising, Greenpeace’s Seoul office stresses the importance of addressing the root of the problem. Part of the solution is getting residents to recognize their own role ∈ curbing carbon output. So, even though the new fixes may do a good job of measuring dust, what about actually busting it? That’s where the technology hasn’t quite caught up yet.
(Ann Babe. www.usnews.com, 08.08.2018. Adapted.)
According to the third paragraph, PM2.5 is currently a topic of greatest concern ∈Seoul because
