Moscow's environmental monitoring agency announced Saturday that the capital's air had cleared up after days of mystery pollutants blanketing the atmosphere, Interfax reported.
"Data from MosEcoMonitoring on Nov. 22 did not show any increase in major pollutants," a spokesman for the agency was cited as saying by Interfax.
The agency had been using 46 automatic monitoring stations throughout the city to keep a close eye on air quality after a series of warnings by city officials in recent weeks that residents should stay indoors and shut the windows to avoid breathing in unknown pollutants.
The city had been plagued by pollutants since Nov. 11, when the Emergency Situations Ministry said an increase in hydrogen sulfide had been detected but there was no threat to the health of city residents.
Days after that, the ministry posted an online statement warning residents of "harmful impurities" in the city's air, advising people to wear face masks to prevent breathing in smoke from burning woodland.
In the most recent case, last Friday, emergency services officials again warned city residents to stay indoors if possible, with the federal meteorological watchdog Roshydromet blaming the situation on the burning of logging waste in the south of the city, Interfax reported.