The China Meteorological Administration announced a yellow alert on Monday morning, saying sandstorms had spread from Inner Mongolia into the provinces of Gansu, Shanxi and Hebei, which surrounds Beijing, Trend reports citing Reuters.
Neighbouring Mongolia was also hit by heavy sandstorms, with at least 341 people reported missing, according to China’s state news agency Xinhua. Flights have been grounded out of Hohhot, capital of Inner Mongolia.
Beijing’s official air quality index reached a maximum level of 500 on Monday morning, with floating particles known as PM10 rising beyond 8,000 micrograms per cubic metre in some districts, according to the city’s environmental monitoring centre.
The World Health Organization recommends average daily PM 10 concentrations of no more than 50 micrograms.
Readings of PM2.5, smaller particles that infiltrate the lungs, were also above 300 micrograms per cubic metre, far higher than China’s standard of 35 micrograms.