VIENTIANE, March 25 (Xinhua) -- Air quality in Laos has worsened, with PM 2.5 fine particles reaching hazardous levels, affecting cities across the country, according to the Lao Ministry of Natural Resources and Environment.
The air quality index in the northern province of Xayaboury has reached a hazardous level, with PM 2.5 concentration hitting 284 micrograms per cubic meter, exceeding the safety threshold of 50 micrograms per cubic meter, according to the report on Tuesday.
The provinces of Xieng Khuang, Sekong, and Lao capital Vientiane, also saw PM 2.5 levels surpassing 260 micrograms per cubic meter, reaching hazardous levels.
PM 2.5, the fine particulate matter that causes smog, is an air pollutant containing tiny particles with a diameter of less than 2.5 micrometers.
PM 2.5 can lodge in the lungs and enter blood vessels, leading to respiratory and cardiovascular disease. ■