Africa has an air pollution problem – but lacks the data to tackle it

Another smoggy day in Abidjan. Image: Getty.

The World Health Organisation (WHO) recently launched BreatheLife, a campaign to make people more aware about the fact that air pollution – which it calls the invisible killer – is a major health and climate risk.

“Invisible” may refer to the lack of awareness that air pollution is a major health risk. In fact, air pollution levels exceeding the WHO air quality guidelines are often very visible, particularly in developing countries. This is especially true for billions of people living in close contact with air pollution sources. Those who, for example, cook on inefficient stoves with fuels such as coal. Or live in an industrial area.

The WHO has air quality programmes for most of the world’s regions. These review the effects of air pollution on health and help countries develop sustainable air quality policies. But none exists for sub-Saharan Africa. It is not clear why. A possible explanation may be that environmental health risk factors are overshadowed by other risks like malnutrition, HIV, tuberculosis and malaria.

Despite this, we do know something about the continent’s air pollution levels. In the first major attempt to estimate the health and economic costs of air pollution in Africa, an Organisation for Economic Co-operation and Development report found that air pollution in Africa already causes more premature deaths than unsafe water or childhood malnutrition. It warned that this could develop into a health and climate crisis.

But how bad are air pollution levels in Africa? Which countries have the worst air pollution levels? What are the main sources and drivers of air pollution? Are the main sources and drivers of air pollution different from those on other continents?

The answers to these questions are severely hampered by a lack of data as well as poor regulation and laws in African countries. The only country on the continent that has ambient air quality standards enforced by air quality laws and regulations is South Africa. Other countries have either ambient air quality standards or air quality laws and regulations, or none at all.

What’s known

Air pollution is a complex mixture of many components.

The WHO’s air quality guidelines, as well as country-specific laws, have identified a few air pollutant components: particulate matter smaller than 2.5 micrometer (PM2.5) and 10 micrometer (PM10) in aerodynamic diameter, sulphur dioxide (SO2), ground-level ozone (O3), carbon monoxide (CO), benzene, lead and nitrogen dioxide (NO2).

The most dangerous are PM2.5 and ultrafine particles (UFP); the latter are smaller than 100 nanometer in aerodynamic diameter. PM2.5 and UFP penetrate deeper into the lung alveoli and may pass into the bloodstream. PM10 and PM2.5 are important indicators of long-term air quality and of health risks.

Based on data of ground measurements conducted in 2008-2015, Africa’s PM10 levels are not the highest in the world.

The database is the largest of its kind and covers over 3,000 human settlements – mostly cities – in 103 countries. The number one spot belongs to the Eastern Mediterranean region, followed by the South-East Asia region and then Africa. But the WHO acknowledges numerous limitations to the data sources. Fewer sites globally measure PM2.5, hence the focus is on PM10.

The PM2.5 data based on the WHO air quality model show that the number one spot again belongs to the Eastern Mediterranean region, followed by the South-East Asia region and then Africa. Given the lack of PM2.5 ground measurements in Africa, the PM2.5 data derived from the WHO air quality model for Africa should be viewed with caution.


Where is the air worse in Africa?

It is hard to say what the real picture is. The modelled PM2.5 data supplements the data from ground monitoring networks, especially in regions with no or very little monitoring, as is the case in Africa.

The PM10 data, based on ground measurements conducted between 2008 and 2015, show that all African countries with PM10 data exceeded the WHO annual guideline of 20 microgram/cubic meter (µg/m³).

Onitsha in Nigeria had the highest yearly PM10 level of 594 µg/m³ globally, nearly 30 times higher than the WHO annual guideline. But the quality of the data is questionable. The level for Onitsha is based on PM10 data collected only in 2009 and only at one site. The database also does not mention on how many days the 2009 yearly level is based as missing data can lead to a distorted yearly level. The lowest yearly PM10 level was recorded at Midlands in Mauritius (20 µg/m³). But this is based only on 2011 data collected again at only one site without mention of how many days in 2011 were measured.

It is also difficult to know exactly what the contribution of different sources of air pollution are in Africa.

The amount of air pollution in any given location is affected by a combination of local, regional and distant sources. It is also affected by the dispersion of pollutants, which in turn depends on numerous weather conditions such as wind direction, temperature and precipitation.

A recent review indicated that very few studies in Africa conducted source apportionment of PM2.5 and PM10. The review concluded that (based on the few studies) 17 per cent, 10 per cent, 34 per cent, 17 per cent and 22 per cent of PM2.5 levels in Africa are due to traffic, industry, domestic fuel burning, unspecified source of human origin and natural sources - such as dust and sea salt. For PM10 the corresponding source distribution is 34 per cent, 6 per cent, 21 per cent, 14 per cent and 25 per cent, but should be viewed with caution due to the few studies.

Based on the limited number of PM10 and PM2.5 source apportionment studies in Africa, these tentative conclusions can be drawn. Traffic is a major source of PM10 levels in Africa as in many other global regions. The other two major sources of PM10 in Africa are domestic fuel burning and natural sources. In other regions of the world, industry and the ambiguous “unspecified source of human origin” contribute more.

Domestic fuel burning is the major source of PM2.5 in Africa, followed by traffic and natural sources such as dust. In other regions of the world, traffic, industry and the ambiguous “unspecified source of human origin” contribute more to PM2.5 levels.

Air quality interventions

Regardless of the exact global source contributions, the main sources of air pollution should be tackled globally in management plans and interventions.

Obvious interventions include clean energy technology such as solar power, to minimise domestic fuel burning and emissions from coal-fired power plants. Other initiatives include clean public transport, bicycle lanes to cut traffic emissions, recycling and controls on industrial emissions.

Air pollution does not stop at country or continental borders. It is a major risk factor for climate change. A disregard for air pollution levels in Africa may have a major impact on global climate change in the years to come.The Conversation

Janine Wichmann is associate professor at the University of Pretoria.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

The Thessaloniki dig problem: How can Greece build anything when it’s swarming with archaeologists?

Archaeological finds on display in an Athens metro station. Image: Gary Hartley.

It’s fair to say that the ancient isn’t much of a novelty in Greece. Almost every building site quickly becomes an archaeological site – it’s hard to spin a tight 360 in Athens without a reminder of ancient civilisation, even where the city is at its ugliest.

The country’s modern cities, recent interlopers above the topsoil, serve as fascinating grounds for debates that are not just about protecting the ancient, but what exactly to do with it once it’s been protected.

The matter-of-fact presentation that comes with the many, many discoveries illustrates the point. Athens often opts to display things more or less where they were found, making metro stations a network of museums that would probably take pride of place in most other capitals. If you’re into the casual presentation of the evocative, it doesn’t get much better than the toy dog on wheels in Acropolis station.

That’s not even close to the extent of what’s available to cast an eye over as you go about your day. There are ruins just inside the city centre’s flagship Zara store, visible through the glass floor and fringed by clothes racks; Roman baths next to a park cafe; an ancient road and cemetery in an under-used square near Omonia, the city’s down-at-heel centre point.

Ruins in Zara. Image: Gary Hartley.

There is undoubtedly something special about stumbling upon the beauty of the Ancients more or less where it’s always been, rather than over-curated and corralled into purpose-built spaces, beside postcards for sale. Not that there isn’t plenty of that approach too – but Greece offers such sheer abundance that you’ll always get at least part of the history of the people, offered up for the people, with no charge attached.

While the archaic and the modern can sit side by side with grace and charm, economic pressures are raising an altogether more gritty side to the balancing act. The hard press of international lenders for the commercialisation and privatisation of Greek assets is perhaps the combustible issue of the moment – but archaeology is proving something of a brake on the speed of the great sell-off.

The latest case in point is the development of Elliniko – a site where the city’s decrepit former airport and a good portion of the 2004 Olympic Games complex sits, along the coastal stretch dubbed the Athens Riviera. With support from China and Abu Dhabi, luxury hotels and apartments, malls and a wholesale re-landscaping of several square kilometres of coastline are planned.

By all accounts the bulldozers are ready to roll, but when a whole city’s hovering above its classical roots, getting an international, multi-faceted construction job off the ground promises to be tricky – even when it’s worth €8bn.


And so it’s proved. After much political push and shove over the last few weeks, 30 hectares of the 620-hectare plot have now been declared of historical interest by the country’s Central Archaeological Council. This probably means the development will continue, but only after considerable delays, and under the watchful eye of archaeologists.

It would be too easy to create a magical-realist fantasy of the Ancient Greeks counterpunching against the attacks of unrestrained capital. The truth is, even infrastructure projects funded with domestic public money run into the scowling spirits of history.

Thessaloniki’s Metro system, due for completion next year, has proved to be a series of profound accidental excavations – or, in the immortal words of the boss of Attiko Metro A.E., the company in charge of the project, “problems of the past”.

The most wonderful such ‘problem’ to be revealed is the Decumanus Maximus, the main avenue of the Byzantine city – complete with only the world’s second example of a square paved with marble. Add to that hundreds of thousands of artefacts, including incredibly well-preserved jewellery, and you’ve a hell of a haul.

Once again, the solution that everyone has finally agreed on is to emulate the Athens approach – making museums of the new metro stations. (Things have moved on from early suggestions that finds should be removed and stored at an ex-army camp miles from where they were unearthed.)

There are other problems. Government departments have laid off many of their experts, and the number of archaeologists employed at sites of interest has been minimised. Non-profit organisations have had their own financial struggles. All of this has aroused international as well as local concern, a case in point being the U.S. government’s renewal of Memorandums of Understanding with the Greek state in recent years over protection of “cultural property”.

But cuts in Greece are hardly a new thing: lack of government funding has become almost accepted across society. And when an obvious target for ire recedes, the public often needs to find a new one.

Roman baths in Athens. Image: Gary Hartley.

Archaeologists are increasingly finding themselves to be that target – and in the midst of high-stakes projects, it’s extremely hard to win an argument. If they rush an excavation to allow the quickest possible completion, they’re seen as reckless. If they need more time, they’re blamed for holding up progress. 

Another widely-told but possibly-apocryphal tale illustrates this current problem. During the construction of the Athens Metro, a construction worker was so frustrated by the perceived dawdling of archaeologists that he bought a cheap imitation amphora in a gift shop, smashed it up and scattered the fragments on site. The worthless pieces were painstakingly removed and analysed.

True or not, does this tale really prove any point about archaeologists? Not really. They’re generally a pragmatic bunch, simply wanting to keep relics intact and not get too embroiled in messy public debates.

It also doesn’t truly reflect mainstream attitudes to cultural capital. By and large, it’s highly valued for its own sake here. And while discoveries and delays may be ripe for satire, having history’s hoard on your doorstep offers inconveniences worth enduring. It’s also recognised that, since tourists are not just here for the blue skies, good food and beaches, it’s an important money-maker.

Nonetheless, glass malls and shiny towers with coastal views rising from public land are good for the purse, too – and the gains are more immediate. As the Greek state continues its relentless quest for inward investment, tensions are all but guaranteed in the coming years. 

This is a country that has seen so many epic battles in its time it has become a thing of cliché and oiled-up Hollywood depiction. But the latest struggle, between rapacious modernity and the buried past, could well be the most telling yet. 

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