From the orange-tinged snow in Russia to schoolkids in Cyprus banned from playing outdoors, the dust-laden skies of recent weeks have become the major topic of conversation.
Social media has been atwitter with possible causes – the war in Syria and climate change are the most common – and duration – the dust storms are much more frequent than they used to be.
Though scientists concede there are unknowns, essentially the facts are straightforward. Climate change is certainly a factor, the war in Syria is almost certainly not. And while the dust ‘episodes’ do last longer than they used to, the amount has not risen. It is the increased number of official announcements on dust levels that is the main source of the belief that they have got worse. Put simply, the public is now better informed.
In Cyprus, desert dust from the Sahara is the main cause of the high levels which descended in recent weeks.
The dust is always in the atmosphere, usually in the higher altitudes, but a number of factors determine whether it will come low enough so we breathe it in, which is what the department of air quality at the labour inspection department is concerned with. Factors can be wind speed, wind directions and the pressure system in the area.
Actually, the labour inspectors don’t like to talk about simply dust.
“We report particles of an aerodynamic diameter smaller than 10 µm,” labour inspection officer Chrysanthos Savvides who is in charge of air quality explained.
These are indeed really small, as 1 µm equals 1 millionth of a metre or 1 thousandth of a millimetre. A human hair has a diameter of 50 µm, meaning five particles would fit on the width of it. This means people don’t filter them by breathing and they end up deep in the lungs and we get more of them because they can travel over longer distances than bigger particles.
What they consist of is not simply dust, but a number of liquids and solids. “There are thousands of chemicals present in them, of which we measure some according to EU guidelines,” Savvides told the Sunday Mail.
Apart from real-time monitoring equipment at the 14 stations around Cyprus another method, called gravimetric is used. This requires the analysis of special filters in a scientific laboratory and provides more specific information.
With these measurements the department can also determine where the particles come from, and, what is important for the European Union, whether the causes are human activity or the physical location of a place. More about this later.
“Some of it comes because we are close to African countries and deserts,” Savvides said. The phenomenon is, he said, not due to the war in Syria, at least there is no evidence for this popular idea.
“There are never absolute zero levels [of various chemicals], but they may be so small that they are recorded as zero.”
Marina Neophytou, associate professor in environmental engineering at the University of Cyprus, says the dust from the Sahara is so difficult to deal with once the particles are on the move.
“During the last couple of years an intensity has been observed,” she said, blaming climate change.
Savvides confirmed that the lack of rain in the African region over the past decade has worsened the situation, and activities by people which stir up the sand, such as car races in the desert, also mean more of the light dust goes into the air.
Once there it can travel far, as Russia’s orange snow shows.
Like Savvides, Neophytou said there is little evidence that the war in Syria is having an impact on dust levels. Most of the problematic dust originates in Africa. She said with the wind sometimes coming from the east, it could not be completely ruled out that some chemicals in the air come from Syria but evidence would be hard to obtain.
“We can’t see the chemicals, and we don’t know which ones might be used in the area so we can’t measure them,” she said, “but we can see the desert dust.”
What is sure, she added, is that the particles impact people’s lives, they can cause respiratory problems, and they carry bacteria which can give rise to infections.
Not only are they a problem for human health, but for life in general, as the dust also settles on water reservoirs, in plants and on solar panels.
With climate change and desertification, the EU is looking for a solution to mitigate the effects and the University of Cyprus is taking part in the life-Medea project which aims to find strategies, hopefully in the near future.
Although dust episodes last longer than they used to, there are actually as many episodes – with PM10 levels higher than 50 μg / m3 – as there were years ago.
In 2015 the air quality department decided to issue regular announcements when the safe level is surpassed, a move that contributed a lot to the general view that there is now more dust while they are mainly just better informed.
Before 2011 no announcements at all were made, and while five were issued in 2012, by applying today’s criteria there would have been 14 during that year.
European Union directives now specify a number which is the limit for ‘good’ air, and EU countries are not allowed to exceed this level more than 35 days a year. In Cyprus, the 50 μg / m3 of PM10 particles exceeds 70 to 100 days each year.
How does Cyprus get away with exceeding the 35-day limit?
This is where the anthropogenic factor comes in. The 35 days are calculated by how many are mainly caused by deserts and salt, physical factors, and those caused by human activity in the country in question.
The EU, knowing that southern European countries cannot help being affected by their proximity to deserts, takes into account how harmful human activity in each country is. Here, Cyprus has actually improved. From 35 days in 2010 the days with an hourly average of more than 50 µm gradually decreased to less than 15 in 2016.
The inspectors can tell which the factors are by analysing the content of the particles. Only dust coming from deserts contains aluminium and iron, whereas sea salt includes sodium, magnesium and chlorine.
The remaining which don’t have these metals have anthropogenic sources.
Of the human activities, 50 per cent of pollutants come from industry, mainly from cement and electricity production. Other sources are transport with 20 per cent, agriculture (25 per cent) and heating and fireplaces (5 per cent).
To see if the composition of the particles smaller than 10 µm has changed over the years, the department keeps statistics, which show that it hasn’t, at least not in recent years. From 2013 to 2016, desert sands account for 30 per cent of the content, sea salt 5 per cent and human activities 65 per cent.
Since the human element is largely constant any changes are caused by the desert dust.
Though there was a really bad day in September 2015 when dust levels were not just in the hundreds but in the thousands, contrary to what many believe summer is not the main season for high dust levels. “A big proportion of them are in January to April,” Savvides said.
In terms of how to mitigate the effects of dust, the good news is that any mask is effective, even a wet cloth held over the nose will work, he added.
What exactly a mask can achieve is not clear though.
“There are no data on the effect of various recommendations that people comply with,” practising physician and professor of paediatrics Panayiotis Yiallouros commented.
He said people should remain calm as the latest reports have caused a lot of anxiety.
“Now everybody is focusing on dust, patients are saying I had an asthma attack because of the dust, without considering other factors like infection.”
One can say high dust levels cause more cardiovascular and respiratory problems, but the reasons for such health problems cannot be isolated.
He is not the only one who thinks the particles have attracted a little too much attention.
During the hour I spent interviewing Chrysanthos Savvides, the head of the air quality department, he answered the phone a dozen times, every one of them to explain to concerned kindergartens, schools and sports organisers that the level of 60 µm did not mean they should keep children inside at all times and cancel sport events, but only that they should keep an eye on those who have health problems such as asthma.
He said he sometimes wondered whether it was a good move to issue all their warnings, as people tended to overreact.
As soon as I went back to the office, by now convinced by the expert that this was just one of the many days when dust levels are very slightly elevated, I spoke to a friend on the phone.
“All this dust is killing me today,” she said.
