SEOUL (Reuters) - South Korea closed schools on Monday and its factories producing memory chips stepped up safeguards, as a choking pall of sand mixed with toxic dust from China covered most of the country and other parts of Asia. The annual "yellow dust" spring storms, which originate in China's Gobi Desert before sweeping south to envelop the Korean peninsula and parts of Japan, are blamed for scores of deaths and billions of dollars in damage every year in South Korea.
It issued a yellow dust warning at the weekend. On Monday, school districts in southeastern regions urged parents to keep kindergarten and elementary school children at home.
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The sand storms have been increasing in frequency and toxicity over the years because of China's rapid economic growth and have added to increased tensions with neighbors South Korea and Japan over recent years. The dust picks up heavy metals and carcinogens such as dioxin as it passes over Chinese industrial regions, before hitting North and South Korea and Japan, meteorologists say.
Dry weather and seasonal winds in China hurl millions of tons of sand at the Korean peninsula and Japan from late February through April or May, turning the skies to a jaundiced hue. The state-sponsored Korea Environment Institute said the dust kills up to 165 South Koreans a year, mostly the elderly or those with respiratory ailments, and makes as many as 1.8 million ill. Annual economic damage to South Korea from the storms is estimated at up to 5.5 trillion won ($5.82 billion), according to the institute.
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http://www.enn.com/ecosystems/article/32120