Serbia has been accused of manipulating data in a bid to play down its air pollution problem.
The country has been under increased scrutiny since a December 2019 report claimed it had Europe's worst per capita record for pollution-related deaths: 175 per 100,000 people.
A few months earlier, a real-time worldwide ranking put the capital Belgrade in the world's worst top five cities for PM 2.5 air pollution.
Now, say activists, the new government (elections were held last June) is doing everything it can to downplay the issue.
Pollution chief sacked after data spat
In December, Milenko Jovanovic was fired as head of the air quality department at the Serbian Environmental Protection Agency (SEPA).
The official reason for sacking him after 17 years of service was because he opposed his superiors and Serbia's air quality monitoring stations were not properly maintained. Jovanovic and other experts say the latter claim is untrue.
Instead, Jovanovic believes he was sacked because he objected to a reclassification of what constitutes air pollution.
He said SEPA wanted to change the threshold of PM 2.5 pollution, which like PM 10 are tiny dirt particles that come from power plants, motor vehicles and agricultural burning, to name but a few sources. They're considered dangerous because their size means they can penetrate deep into people's lungs.
Jovanovic says under the changes, 40 micrograms per cubic metre of PM 2.5 is no longer classified as pollution, instead it's now acceptable.
The threshold for what is considered heavily polluted and extremely polluted air has also been increased, he added. The categories of what is classified as good and excellent air quality remain unchanged.
Jovanovic told Euronews it was significant the change was made around winter when pollution is at its worst.
Experts should have been consulted about the changes, he added.
"None of that was done," he said. "It was simply introduced overnight and I objected it for which I have suffered consequences.
"You can not say that today, with this data that we have, [the] air is polluted and dangerous and the following day, with [the] same results, but with authorities changing the classification, that the air is clean. It does not go like this.
"The quality of the air stays the same but [the] representation of the results to the public is changed, which is manipulation."
Ognjan Pantic, a project coordinator at Belgrade Open School, a civil society organisation that works on air pollution issues, said that Jovanovic had been very transparent in the past about communicating Serbia's air pollution problem.
"I think the entire environment agency is under pressure from the government to talk less about the issue of air pollution.
"The government in Serbia is really aggressive at controlling any form of criticism. It controls huge parts of the media and can control the narrative. Anyone pointing out something is immediately accused of working against their own government."
How bad is the pollution in Serbia?
Pollution in Serbia and in other parts of the Balkan peninsula is so bad in autumn and winter it can be seen, smelt and even tasted.
Respite sometimes comes in the form of Košava, a cold wind that blows in from the Carpathian Mountains.
But as soon as this stops, the pollution returns.
In winter, pollution can be so bad in some towns and cities that it's like a stereotypical scene from the Dickensian era. But, unlike 19th century London, there is little industry. Most of the dirty air comes from heating, both private and public, and motor vehicles.
Belgrade, meanwhile, is surrounded by the coal power plants and the lignite mines that power them -- all inherited from socialist times.
"Most harmful for human health are the fine and ultra-fine particles PM 10 and PM 2.5," said Elizabet Paunovic, the former head of the World Health Organization's (WHO) European Centre for Environment and Health.
"By WHO recommendation, the maximum of the PM 2.5 particles should be 10 micrograms per cubic metre, on an annual average level.
"But, in Belgrade, it was 29.2 micrograms per cubic metre. Reducing this value for just 5 micrograms could save hundreds of lives.
"In some cases, during days when PM 2.5 particles are higher than levels recommended by WHO, there is an increase in mortality in Belgrade."
What is the government doing to tackle the problem?
Serbia's prime minister Ana Brnabic has denied that Belgrade is one of the most polluted major cities.
She admitted there are "some problems" regarding pollution but said the government is doing "a lot" to solve them, without specifying any further.
Critics question whether the reclassification of what constitutes pollution is among Belgrade's solutions.
"The change in criteria for pollution shows that there is manipulation with data," said Mirko Popovic, programme director at the Renewables and Environmental Regulatory Institute. "It shows citizens that they can not trust their own government.
"Belgrade is sensitive when it comes to global climate change. Parts of it are extremely vulnerable and, on those parts, the government is planning to build. From those decisions, you can see that there is no plan or will to solve the problems.“
He said urban development is not just hurting the green parts of Belgrade but is adding to the cumulative effect of the pollution.
"Experts warned that [the] flow of air will be cut off by building the new tower in the Sava amphitheatre," Paunovic added. "However, experts were not listened to and the airflow that runs through here is cut off."
In the part of New Belgrade where the tower was built pollution is usually above the local and EU limits.
Other plans include building on one of the Serbian capital's rare forests.
“Kosutnjak forest is the lungs of Belgrade," said Bojan Simisic, a member of Eco Watch, a Serbian environmental organisation.
"It can be seen that the local government is chopping trees instead of planting them. In order to lower pollution, we should plant trees, not chop them down."
Euronews contacted the Serbian government, SEPA and Belgrade's ecology department to respond to criticism in this article. None had responded by the time of publication.
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