Contradicting measurements showing pollutant levels exceeding international guidelines, the Environment Ministry on Friday issued a statement claiming “there is no serious air pollution yet” in Phnom Penh.

“[P]lease be aware of this and please do not worry about safety in travelling and working outdoors,” reads the ministry’s statement, which claims to rebut reports of unhealthy levels of pollution in the capital, though it does not specify the reports it is contesting.

The statement adds that the ministry will inform the public of any irregularity in air pollution levels.

However, according to one standard measurement of air pollution – PM 2.5, or particulate matter smaller than 2.5 microns wide – Phnom Penh has regularly exceeded recommended pollutant levels, beyond which residents increase their risk of disease and death. Air pollution has been linked to a wide range of respiratory and cardiovascular diseases.

The Environment Ministry installed air quality sensors in Phnom Penh in 2017 to monitor PM 2.5 levels. While data for April and the entirety of March were not immediately available on Sunday, previous ministry data shared with The Post show PM 2.5 readings averaging 21.35 micrograms per cubic metre in January, 37.27 in February, and 28.01 through mid-March.

The World Health Organization’s exposure guidelines warn of increased risks beyond an average of 25 micrograms per cubic metre of PM 2.5 for every 24-hour period.

Thiv Sophearith, head of the ministry’s air quality office, said on Sunday that the ministry would make its air quality data public online and on Facebook in the next week, but did not respond to a request to clarify the ministry statement.

Data from AirVisual, a company that collates live air quality monitoring from cities around the world, show a daily PM 2.5 reading of 47.5 micrograms per cubic metre on April 6, 42.5 on April 22, and 37.2 on April 14.

Most days in April exceeded the WHO guideline of 25 micrograms per cubic metre, though this month readings from all but one day have been below the threshold.

According to a 2018 report by the US-based Health Effects Institute, a non-profit funded by the US government and global automotive industry, PM 2.5 pollution in Cambodia is responsible for 72.6 deaths per 100,000 people, based on 2016 data. Globally, the average is 62.5 deaths per 100,000 people.

For over a week in March this year, the city landfill in Dangkao district caught fire, choking residents in a putrid haze. The burning of rubbish is known to release dangerous compounds such as dioxins – which have been linked to a variety of developmental illnesses and cancer risk – though the levels of such toxins are not currently measured.

Additional reporting by Phak Seangly