Ozone problem in S.Korea gets worse

(THE CHOSUN ILBO) The ozone problem is worsening in major cities in Korea. Ozone is a harmful gas produced when nitrogen oxide from diesel exhaust reacts with ultraviolet rays.

The government has spent a lot of money over the last decade to improve air quality in the Seoul metropolitan area, but ozone levels are still rising.

According to the Environment Ministry, the ozone concentration in Seoul has increased from 17 ppb (particles per billion) in 2005 to 23 ppb last year, up around 35 percent.

The number of ozone alerts in the capital increased from three to 23 times over the same period. Typically, if the ozone concentration rises by 10 ppb, the chances of respiratory problems increase and the mortality rate also rises around 0.9 percent.

Environmentalists blame the government's failure to reduce diesel car emissions although it knew that they spew out more nitrogen oxides than petrol.

But some of the blame must go to China. Kim Jeong-soo of the National Institute of Environmental Research said, "More ozone created in China is traveling across the ocean into Korea" as the numbers of motorists there skyrocket.

The number of cars on the streets of China increased almost five-fold from 31.6 million in 2005 to 154 million last year.