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.


Worried Guildford will be destroyed by Chinese trains? Then you might not be very nice

A South West Train at Waterloo. Image: Getty.

Despite the collapse of everything else that more-or-less worked in 2008 Britain, before the Hunger Games years began, some things remain constant. One of the things that’s near-mathematical in its constancy is that, when a new train contract is let, people on both sides of the political spectrum will say extremely stupid things for perceived partisan advantage.

This week saw the award of the contract to run trains to the south west of London, and unsurprisingly, the saying stupid things lobby was out in force. Oddly – perhaps a Corbyn-Brexit trend – the saying of egregiously stupid racist lies, rather than moderately stupid things, was most pronounced on the left.

As we’ve done to death here: rail in Great Britain is publicly run. The rail infrastructure is 100 per cent publicly owned, and train operators operate on government contracts, apart from a few weird anomalies. Some physical trains are owned by private investors, but to claim rail isn’t publicly run would be like claiming the NHS was the same as American healthcare because some hospital buildings are maintained by construction firms.

Every seven years or so, companies bid for the right to pay the UK government to operate trains in a particular area. This is the standard procedure: for railways that are lossmaking but community-important, or where they are within a major city and have no important external connections, or where there’s a major infrastructure project going on that’ll ruin everything, special measures take place.

The South Western England franchise is not one of these. It’s a profitable set of train routes which doesn’t quite live up to its name. Although it inherited a few Devon and Dorset routes from the old days, its day job involves transporting hundreds of thousands of Reginald Perrins and Mark Corrigans from London’s outer suburbs and Surrey, Hampshire and Berkshire’s satellite towns to the grinding misery of desk jobs that pay a great deal of money.

(If your office is in the actual City of London, a fair trek from the railway’s Waterloo terminus, then you get the extra fun of an extra daily trip on the silliest and smelliest Tube line, and you get even more money still.)

Anyway. The South Western concession went up for auction, and Scottish bus and train operator First Group won out over Scottish bus and train operator Stagecoach, the latter of which had run the franchise for the preceding 20 years. (Yes, I know 20 isn’t a multiple of 7. Don’t ask me to explain, because I can and you wouldn’t enjoy it.)

First will manage the introduction of a bunch of new trains, which will be paid for by other people, and will pay the government £2.2bn in premiums for being allowed to run the service.

One might expect the reaction to this to be quite muted, because it’s quite a boring story. “The government does quite a good deal under which there’ll be more trains, it’ll be paid lots of money, and this will ultimately be paid back by well-paid people paying more train fares.” But these are not normal times.

First Group has decided for the purposes of this franchise to team up with MTR, which operates Hong Kong’s extremely good metro railway. MTR has a 30 per cent share in the combined business, and will presumably help advise First Group about how to run good metro railways, in exchange for taking a cut of the profits (which, for UK train franchises, tend to be about 3 per cent of total revenue).

The RMT, famous for being the least sensible or survival-oriented union in the UK since the National Union of Mineworkers, has taken exception to a Hong Kong company being involved in the railways, since in their Brexity, curly sandwich-eating eyes, only decent honest British Rail has ever delivered good railways anywhere in the world.

“A foreign state operator, in this case the Chinese state, is set to make a killing at the British taxpayers’ expense,” the RMT’s General Secretary Mick Cash said in a press release.

This is not true. Partly that's because a 30 per cent share of those 3 per cent profits is less than 1 per cent of total revenues, so hardly making a killing. Mostly, though, it’s because it’s misleading to call MTR “state-owned”. While it’s majority owned by the Hong Kong government (not the same body as the central Chinese state), it’s also partly listed on the Hong Kong Stock Exchange. More to the point, this a really odd way of describing a transport authority controlled by a devolved body. I wouldn’t call the Glasgow subway “UK-state owned” either.

So this fuss is intensely, ridiculously stupid.

There’s an argument – it’s a bad argument, but it exists – that the entire UK rail system should be properly privatised without government subsidy.

There’s an argument – it’s a slightly less stupid argument, but it exists – that the entire UK rail system should be returned to the public sector so we can enjoy the glory days of British Rail again.

The glory days of British Rail, illustrated in passenger numbers. Image: AbsolutelyPureMilk/Wikipedia.

But to claim that the problem is neither of these things, but rather that the companies who are operating trains on the publicly run network are partially foreign owned, makes you sound like a blithering xenophobe.

In fact, if you think it’s reasonable for a Scottish company to run trains but not for a Hong Kong company to run them, then that's me being pretty bloody polite all things considered.

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