The return of PM2.5 dust particles in the atmosphere has triggered concern across the country, especially since the government had given the impression that this year's recurrent smog season had ended.
Over the weekend, the ultra-fine harmful dust particles shrouded large parts of the country, with several provinces registering over 200 microgrammes per cubic metre (μg/m³) of PM2.5 matter -- above the national "safe" threshold of 50μg/m³, which is still much higher than the standard set by the World Health Organization at 25μg/m³.
