Qualité de l’air en Uganda

Is the air in Uganda badly polluted?

Uganda is a country in Africa, located in the east-central region of the continent, being surrounded by other countries such as Sudan, the Democratic Republic of the Congo, Rwanda and Tanzania. It shares a portion of Lake Victoria with other neighboring countries, as well as residing within the Nile basin. Despite being landlocked, Uganda has a great many lakes and large bodies of water within it, with many important cities being located next to these places, including the capital city of Kampala.

In terms of economy and industry, Uganda has seen a consistent amount of growth in recent times, with large amounts of exports based around food produce such as coffee, fish and maize, as well as industrial items such as metals and oil. As the economy continues to grow, there is a subsequent rise in the population number, as well as an increase in urbanization, infrastructure and industrial facilities. This has the knock on effect of causing the country to have worsened levels of air quality, due to the increased amount of industrial activity and rise in anthropogenic activity. This in turn has led to some highly polluting practices occurring within the country, due to lack of stringent measures to protect against environmental issues, as well as a lack of adequate enforcement for major infractions that threaten the quality of the air, as well as pollution of the soil and water.

In 2019, the capital city of Uganda, Kampala, was recorded as having a PM2.5 reading of 29.1 μg/m³ as its yearly average, a reading that placed it into the higher end of the ‘moderate’ pollution bracket, which requires a PM2.5 reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such. PM2.5 refers to particulate matter that is 2.5 micrometers or less in diameter, going down to sizes as small as 0.001 microns and beyond. This incredibly small size, coupled with the constituents of what make up fine particulate matter, make it incredibly dangerous to human health when respired. This has caused PM2.5 to be used as one of the major components in the calculation of the overall quality of air, along with other prominent pollutants such as PM10, Ozone and nitrogen dioxide.

This placed Kampala in 465^th place out of all cities ranked worldwide, an extremely poor placing that shows that it is sitting in the upper echelons of most polluted cities around the world. Uganda itself as a country also came in with a PM2.5 reading of 40.80 μg/m³ in 2018, and then 29.10 μg/m³ in 2019, a reading that placed it in 22^nd place out of all countries ranked worldwide, coming in just behind other countries such as Ghana and Myanmar. This is highly indicative that Uganda could do much to improve the quality of its air, and to implement measures to drastically reduce pollution for the wellbeing of its citizens, which also requires people on an individual level to take responsibility for their actions.

Why is there air pollution in Uganda?

Uganda has many different sources of pollution, typically compounding each other as they all occur, leading to the heightened levels of PM2.5 on record. A majority of them would arise from combustion sources, and these along have many different causes, each with their own unique polluting footprint. Other issues stem from areas or sites that release large amounts of fine particulate matter, leading to massive buildups of dust and finely ground gravel or silica that can cause severe damage to the health of those who are exposed over lengths of time.

To start with the combustion sources, one of the main ones would be that of vehicle emissions, with the huge (and steadily growing) amount of cars, motorbikes and other small vehicles populating the roads, with countless numbers in use at any given time. These can put out large amounts of dangerous chemicals and hazardous particulate matter, and to compound the situation further, many of them often run on lower quality fuels.

Furthermore, the age and quality of the vehicles themselves are also questionable, with many ancient motors still in use on the road when they should have been retired long ago, but remain in use due to the economic situations many Ugandans find themselves in, as well as lack of stringent road rules in place to remove these offending vehicles. In regards to industrial transportation, the use of heavy duty vehicles is required, which includes lorries and trucks. These also run on diesel fuels and due to their great size and weight often put out far more pollution than a singular vehicle of a smaller size would, hence automobiles are a major contributor to air pollution in Uganda.

Other prominent causes that need mentioning are ones such as cooking stoves inside people’s homes, which often go through copious amounts of firewood and charcoal. This can lead to massive amounts of smoke being released when practiced on a large scale, as well as dangerous buildups of chemicals within households that can inadvertently lead to cases of death when adequate ventilation is not maintained. Other sources are emissions from power plants and factories, both of which would go through large amounts of coal, as well as giving off any industrial effluence related to whatever product is being manufactured. The open burning of waste and garbage is another major issue, and finally construction sites, road repairs and general accumulations of dusts on the road due to lack of sufficient tarmac layers all add up to create large clouds of dust that can be of great detriment to the health of those exposed. These are a number of the causes of air pollution present in Uganda.

When is air pollution at its worst in Uganda?

Using Kampala as the main example to go by, it can be seen that there are certain periods of the year where the air quality is particularly deteriorated and has higher readings of PM2.5 than the rest of the year. Whilst there are many more locations throughout Uganda that also have pollution issues, some of the most up to date and concise data about pollution levels are currently located in Kampala, and hence it will be used to determine air quality fluctuations for the country.

Over the course of 2019, there were some rather sporadic readings taken in Kampala, which differs from other cities around the world which often show a clear cut period of time in which the pollution level is at its worst, and when the air becomes cleaner (with winter colder periods often holding the title of being more polluted than their warmer counterparts).

Some of the most polluted months on record were January to March, and then June through to August, and finally the month of December. All of these months came in above 30 μg/m³, with the worst offenders being February, July and August, which had PM2.5 readings of 36.9 μg/m³, 39.9 μg/m³ and 37.4 μg/m³ respectively. These were all within the ‘unhealthy for sensitive groups’ bracket, with July being the most polluted month of the year with its reading of 39.9 μg/m³. These are the months of the year when the capital would have its air permeated by large amounts of smoke, haze and particulate matter, and whilst this is not truly indicative of the whole country, gives some insight into the sporadic nature of pollution spikes that occur in Uganda.

What are the main types of pollution in the air in Uganda?

With so many different sources of pollution present, there would be a wide variety of different contaminants in the air, many of which arise from the aforementioned combustion sources. The ones that find the majority of their release from vehicles include chemical compounds such as nitrogen dioxide (NO₂) and sulfur dioxide (SO₂), both of which can cause irritation to the lining of the lungs and respiratory tract, as well as contribute to instances of acid rain. Nitrogen dioxide is released so prevalently that areas that see a high volume of traffic will almost always have a high level of nitrogen dioxide in the air above it, to the point that they often have a correlation and can be used to calculate how much pollution is caused by vehicles alone.

Other pollutants include ones such as ozone (O₃), or smog as it is better known when it accumulates in large quantities. This is formed from the various oxides of nitrogen (NOx), which when exposed to solar radiation via sunlight, can undergo a chemical reaction and form ozone. Whilst this is a vital component of the upper atmosphere, when on the ground level it is a highly dangerous pollutant that can cause chest pain, severe coughing, throat inflammation and damage to the lung tissue.

Other pollutants include ones such as black carbon and volatile organic compounds (VOC's), both of which find their origin in the incomplete combustion of both fossil fuels and organic material. VOC's can also be found in a number of household products that contain varnish or adhesives, but in terms of the ones that are released from the combustion of certain materials, prominent ones include chemicals such as methane, propene, ethylene, methanol, benzene, formaldehyde and toluene.

Construction or demolition sites, road repairs as well as poorly maintained roads also have their part to play in the release of dangerous particulate matter (PM2.5 or PM10). These can include finely ground gravel, soil and silica dust, with silica dust being a known carcinogen when inhaled. Other pollutants released from construction or industrial areas include heavy metals such as lead, mercury or cadmium.

Other particularly dangerous pollutants such as polynuclear aromatic hydrocarbons and polychlorinated biphenyls can be released from open burn sites, often where synthetic material is thrown into fires. These are a number of the pollutants that would be found in the air across Uganda, all with their own wide reaching effects on both an individual’s health as well as the environment and ecosystem.

What are some health problems related to breathing polluted air in Uganda?

With a plethora of different pollutants available in the air, as well as subsequent high levels of PM2.5 readings being recorded, there would thus be a large amount of health conditions and ailments that can occur to those who are exposed to excessive amounts of pollution in their day to day lives. These include shorter term ones that usually cease to be a problem when exposure is halted, and include problems such as dry coughs, chest pains, headaches, nausea and vomiting, as well as skin rash breakouts and irritation to the mucous membranes. In terms of more chronic health issues, ones such as higher rates of cancer become apparent amongst the general population, with many cases presenting themselves in people, usually those who work or live in environments where there is high exposure to carcinogenic materials.

Other health issues would be ones such as ischemic heart disease, whereby the heart tissue fails to receive enough oxygen and sustains damage as a result. This can lead to higher rates of heart attacks, as well as other cardiac conditions such as angina and arrythmias. Due to the tiny size of fine particulate matter, it has the insidious ability to enter the blood stream via the lungs, finding its way in via the tiny air sacs, or alveoli. Once in the blood stream, damage to the blood vessels can occur, as well as the material making its way to the far reaches of the body, with the hepatic and renal systems also being at risk for damage (liver and kidneys), as well as reproductive health being affected.

Who is most vulnerable to air pollution in Uganda?

Whilst there are no groups that are fully immune to the negative side effects of air pollution present in Uganda, there are certain demographics that would be even more vulnerable or at risk for a number of different reasons, usually pertaining to age, health or individual disposition. These groups include people such as young children, the elderly, those with preexisting health conditions, as well as those who have compromised immune systems, or hypersensitivity towards certain chemicals, resulting in serious allergic reactions. Pregnant mothers are also particularly vulnerable as well, with overexposure having the possibility to cause instances of miscarriage, as well as babies being born prematurely or with a low birth weight.