Korea was blanketed by acid snow on Monday, with pH dropping to 4.2 on average in Seoul in the morning. Toxic smog compounded the problem as the concentration of fine particles soared to 112㎍/㎥, way above the safe standard of 100㎍/㎥.

The Seoul Research Institute of Public Health and Environment measured the acidity of snow at eight observation spots in the capital between 2 a.m. and 8 a.m. In the afternoon, the acidity level slightly improved to 4.3-4.4 as snow washed pollutants from the city.

Guro-dong and Yangjae-dong had the most acidic snow at pH 3.8 between 7a.m. and 8 a.m., somewhere between orange juice (pH 4.0) and wine (pH 3.5).

Western coastal areas saw the concentration of fine particles reach over 200㎍/㎥, said Kweather, a meteorological information provider. Some areas must have had snow even more acidic than in Seoul, it added.