Pollution in Beijing once again reached dangerously elevated levels on Monday.
A U.S. Embassy monitor recorded pollution levels at 10 times above what is considered safe by the World Health Organization, spurring warnings to stay indoors.
Small particles, which pose the highest risk to humans, reached 242 in the Chinese capital, well above the recommended exposure of less than 25, Bloomberg News reports.
Earlier this month the Chinese government said it would "declare war" on smog by shuttering coal-fired furnaces and taking high-emissions vehicles off the road.
International Monetary Fund Managing Director Christine Lagarde said on Monday that bad air quality, water shortages, and desertification pose a “serious risk to the next stage of China’s development.”