Nearly 90% of Chinese cities failed to meet government pollution standards last year, according to the country's environment ministry.
Although only eight of 74 cities monitored were found to meet national standards, the country's Ministry of Environmental Protection said the results were an improvement over previous years, Reuters reports.
The country declared a "war on pollution" last year and has since taken steps to reduce the use of coal and eliminate factories that don't meet certain standards.
The government has said that meeting its own standards could take up to 15 years. The city of Beijing, for instance, had an average atmospheric pollutant reading of 93 micrograms of particulate matter per cubic meter last year — almost three times the state-determined standard of 35 micrograms per cubic meter.
China—the world's largest polluter— produces a quarter of the world's carbon dioxide emissions.