Invisible pollution can be just as deadly

Just because the pictures from New Delhi are more shocking and obvious, it doesn’t mean Ireland’s air is actually clean. We must act now, write John Sodeau and John Wenger.            

Invisible pollution can be just as deadly

We breathe to live and to do so we inhale and exhale around 11,000 litres of air every day.

Increasingly, people throughout the world are becoming rightly concerned about how “clean” their air is.

While the UN declares access to clean water a fundamental human right, there is no such declaration for clean air. There should be. But to get to that point requires us to understand what we mean by clean air and what risks “dirty air” present to all forms of life on Earth.

The most obvious risks to human health became apparent last week in the reports on New Delhi where a toxic haze blanketed the city.

It was so severe that schools were closed and the chief minister of Delhi state said the city “had become a gas chamber”. That was obvious from the photographs.

We are unlikely to ever see conditions like that in Cork, Galway, or Dublin.

Although that does not mean the air there, or in small towns such as Enniscorthy or Killarney, is clean.

All it means is that we do not see the pollution with such dramatic imagery. Yes, we might see a few photos of the wafting smoke from village chimneys among relentlessly green landscapes but that does not mean the air in Ireland is clean.

Far from it, because the most toxic ingredients of air pollution cannot be seen by our eyes.

Some 99% of the air we breathe is made up of oxygen and nitrogen with varying amounts of water vapour. About 0.1% contains key atmospheric chemicals such as ozone, carbon

dioxide, methane, and nitrogen oxides.

There can be many hundreds more depending upon where you live.

And then there is particulate matter (PM) which is made of airborne particles so small that 500 of them could sit side by side in the width of a human hair.

PM can be particularly dangerous to us because not only can it get into our respiratory systems while carrying carcinogenic chemicals but also enter our arteries causing oxidative damage that leads to the build-up of plaque and then stroke or heart failure.

The smallest PM can even circulate in our blood stream and reach our brains.

The surprising thing to the general public is that air pollutants can have these very adverse effects on our health and wellbeing even when present in tiny amounts, ie parts per billion level.

It is only in the last 20 years or so that we have managed to develop technology to monitor these trace pollutants in real time rather than as historical records. (The difference between the two approaches is like comparing the streaming of a TV programme to sending an old-style camera film to be developed in the local chemists).

What we know now about Ireland’s air, because of real-time monitoring, might shock some people.

For example, burning wood in the fireplace can produce about twice as many small particles as burning smoky coal. Peat is not good either.

Actually, the ambient air in small towns such as Enniscorthy and Killarney is dominated by particles from solid-fuel burning with coal playing a smaller part than wood and peat.

We know this because measurements have been made in an Environmental Protection Agency (EPA) -sponsored project called Sapphire run at University College Cork by our research group in the Centre for Research into Atmospheric Chemistry (CRACLab).

One obvious policy conclusion from this science is that a blanket smoky coal ban may have only a limited effect on air quality if consumers simply move over to wood and peat.

It is clear then that the deployment of real-time air pollution monitoring systems is key to providing us all with early warning systems about the local health of our air.

Indeed, this has been the case in virtually all EU countries for many years now, although not in Ireland, as can be seen by looking at the current real-time air-monitoring networks around the world.

The resulting information is particularly useful to those suffering from respiratory diseases such as asthma and for people with cardio problems. However, most days now we read or hear ever-increasing lists of health problems like diabetes, Alzheimer’s, and abnormal foetal development that are made worse by air pollution.

Therefore, air-quality data is essential to support headlines such as ‘1,500 premature deaths per year attributable to air pollution in Ireland’.

It might be true but until a much more wide-ranging and comprehensive real-time air monitoring network is put into operation in Ireland then the statistics underpinning the numbers are suspect.

The EPA gave us all a very welcome good news story last week with the announcement of its AAMP (Ambient Air-quality Monitoring Programme).

It will provide Ireland, over the next five years, with a hugely expanded air-monitoring capability than it currently enjoys.

Roadside stations, urban sites, and rural locations are all included in the proposed network.

The EPA plans are rightly ambitious and will need local authorities and third-level institutions to help them run the activities.

UCC will get one of these stations and we are certainly on board to feed our data in to the new network co-ordinated by the EPA. The question is: Will local authorities prioritise human and financial resources to run the technology?

As required by the EU Café Directive, up-to-date information on the concentrations of all regulated pollutants in ambient air should be readily available to the public.

Some of the monitoring stations that provide this information are run directly by the EPA. Others are run by city and county councils because local authorities must take whatever measures they consider necessary to prevent or limit air pollution in their area.

But do they?

Galway City has some of the worst traffic jams in Ireland yet it does no real-time air monitoring. In Cork City, PM is measured in real time at only one site and there is no PM monitoring at all in the whole of Co Cork.

Clearly there are higher local priorities.

Unlike many other countries, Ireland has an Air Pollution Act rather than a Clean Air Act. The difference between them is dramatic and, even from a marketing point of view, the first gives a negative message whereas the second is much more positive.

But the important difference from an air-quality perspective is that the Air Pollution Act is focused on legislative pollution limits (set by the EU) for a range of pollutants like PM and nitrogen dioxide. However, a Clean Air Act puts the health of the public front and centre.

In Ireland, a new Clean Air Act should be framed so that local authorities prioritise air monitoring in their budgets. It could allow more stringent air-pollution limits set by the World Health Organisation to be adopted without question.

It would also educate our citizens about the benefits of clean air to our wellbeing and climate. To do this a new or existing independent body should be resourced appropriately to provide us with a fully connected policy on clean air, clean energy, and climate change.

In the meantime we should all approach our local councillors and demand that we get to know if our air is clean with real-time information passed on to us so that we can make appropriate life choices.

Let them know that we know there is something in the air.

John Sodeau is professor emeritus of chemistry at UCC. John Wenger is professor of chemistry at UCC.

Both work in the Centre for Research into Atmospheric Chemistry in both the Environmental Research Institute and School of Chemistry at University College Cork.

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