Uk's Pollution: What's The Main Culprit?

Air pollution is a significant health issue in the UK, causing diseases such as asthma, lung disease, stroke, cancer, and heart disease, and costing the health service, society, and businesses over £20 billion each year. Outdoor pollution alone is estimated to cause 40,000 early deaths each year, with 9,000 of these in London. The UK's air pollution problem has a long history, dating back to the Industrial Revolution when coal-burning made the country the world's leading source of carbon-based air pollution. While the UK has since worked to reduce its reliance on coal, air pollution remains a serious issue, with the country frequently exceeding safe levels of nitrogen dioxide. So, what are the main causes of the UK's air pollution today?

Transport emissions

The UK government has recognised the need to transition to cleaner forms of transportation and has set targets to phase out high-polluting vehicles. By 2040, the government aims to end the sale of new conventional petrol and diesel cars and vans. However, critics argue that this target is not ambitious enough and more urgent action is needed to address the transport sector's contribution to air pollution.

To accelerate the transition to cleaner transportation, the Committee on Climate Change (CCC) has recommended more stringent targets. They suggest that by 2030, 60% of new cars and vans should be ultra-low emission vehicles. Additionally, they urge the government to promote walking, cycling, and the use of public transportation.

The introduction of the Ultra Low Emission Zone (ULEZ) in London in April 2019 is a significant step towards reducing transport emissions. This initiative involves charging older diesel and petrol cars and buses that emit higher levels of pollutants. The ULEZ is expected to reduce road traffic emissions by 20% and has already led to a decrease in the number of highly polluting vehicles entering the zone.

Air pollution is a critical issue in the UK, causing approximately 40,000 premature deaths each year and costing the nation over £20 billion annually. It contributes to various health problems, including asthma, lung disease, stroke, cancer, and heart disease. Therefore, addressing transport emissions is crucial to improving air quality and protecting public health.

Industrial emissions

The UK's steel industry, primarily located in South Wales and the Humber, is a major emitter of industrial emissions, contributing about a fifth of the nation's industrial emissions and 3% of its total CO2 emissions. Cement manufacturing, largely used for concrete production, is also a significant contributor, responsible for around a tenth of the UK's industrial emissions and 2% of its total emissions. These two industries, along with iron and chemicals, were the major emitting subsectors in the UK's transition from a secondary (manufacturing) to a tertiary and service-based economy.

To address industrial emissions, the UK government has set ambitious goals, aiming to cut emissions from industry by two-thirds by 2035 and by 90% by 2050. However, the Industrial Decarbonisation Strategy, published in early 2021, was criticised for lacking new spending or policy initiatives, raising questions about how the UK plans to achieve these targets. One proposed solution is the Clean Steel Fund, announced in 2019, although the specifics of this fund are yet to be disclosed.

To achieve complete decarbonisation, a shift to alternative fuels is necessary. Hydrogen, produced through environmentally friendly methods, and electrification of certain industrial processes, such as glassmaking, are potential solutions. Additionally, improving resource and equipment efficiency, minimising waste, and promoting recycling can also contribute to reducing industrial emissions. Market competition and fuel substitution can also play a role in driving down emissions, as evidenced by studies on the relationship between market concentration, industrial emissions, and innovation.

While the UK has made progress in reducing industrial emissions, particularly through the decline of coal use, there is still a long way to go to meet its emissions targets and mitigate the health and environmental impacts of pollution.

Domestic heating systems

Gas central heating is a common method of heating homes in the UK, with most homes relying on gas from the grid or a tank. However, gas is a major source of pollution, both in the production of heat and the operation of gas systems within homes. Gas central heating loses around 25% of its heat as it travels through radiators, requiring more heat and fuel to warm each room, leading to increased pollution and inefficiency. Additionally, gas systems can emit carbon monoxide, a colourless and odourless poisonous gas that can be deadly. Faulty gas appliances and boilers can release carbon monoxide, which, when combined with other pollutants, forms 'bad' ozone, detrimental to both health and the environment.

In areas without access to the gas mains, homes may be heated using oil, which also has pollution implications. Poorly maintained oil storage tanks can leak, contaminating groundwater and harming local ecosystems. Pipe issues leading to shared tanks can also result in significant pollution that is challenging to remediate.

To combat the pollution caused by domestic heating systems, several alternatives and solutions have been proposed. Smoke control areas have been established by the government, prohibiting the burning of coal or wood for home heating. Instead, residents in these zones can use 'smokeless' coal, environmentally friendly alternatives to logs, or invest in sustainable 'wood-burning stoves'. Electric storage heaters are another option, offering efficient heating without the need for fossil fuels, thus reducing air pollution. These heaters have been installed in numerous homes across the UK, with users reporting increased comfort, better control, and reduced heating bills.

By adopting cleaner heating systems, improving appliance efficiency, and making informed choices, individuals can play a crucial role in reducing air pollution across the UK and safeguarding public health and the environment.

Coal burning

Legislation, such as the Alkali Act of 1863 and the Public Health Act of 1875, were enacted to mitigate the health and environmental impacts of coal burning. However, it was not until the 1950s that the UK began to significantly reduce its reliance on coal. The discovery of North Sea gas and the decline of steam railways, along with increasing globalisation and deindustrialisation, contributed to this transition. As a result, the coal mining workforce decreased significantly, and by 1990, coal mining jobs had dropped to less than 50,000.

Despite these efforts, coal burning continued to be a significant contributor to air pollution in the UK. In 2010, the European Commission (EC) threatened the UK with legal action due to successive breaches of PM10 limit values, which are dangerous airborne particles that can harm human health. The Greater London Built-up Area, in particular, struggled to meet the EC's air quality standards, with high levels of PM10 concentrations estimated to cause 3,000 deaths per year within the city.

To address these concerns, London implemented the Ultra Low Emission Zone (ULEZ) in April 2019, which involved charging older diesel and petrol cars and buses for entering the zone. This initiative successfully reduced the number of polluting vehicles entering the zone and improved air quality in central London. However, coal burning for electricity generation remained a challenge until recently.

In October 2024, the UK achieved a significant milestone by ending its 142-year reliance on coal power. The closure of the Ratcliffe-on-Soar power station near Nottingham marked the last coal-fired power plant in operation, and the UK became the first major economy and G7 member to phase out coal power. This transition is expected to push coal demand to levels not seen since the 1600s and significantly reduce the UK's contribution to climate change.

Nitrogen dioxide

NO2 is a significant contributor to air pollution in the UK, particularly in urban areas. Between 1992 and 2002, annual mean NO2 concentrations in urban areas decreased by an average of 2.7 µg/m3 annually. This positive trend was likely due to reduced nitrogen oxide emissions in the UK and Europe. However, from 2002 to 2006, these concentrations fluctuated without a clear trend, despite continued emission reductions. This period coincided with increased coal use in power stations and a rise in diesel car popularity, which offset the gains made previously.

From 2006 to 2019, urban NO2 concentrations decreased again, this time by an average of 0.9 µg/m3 per year. By 2019, only a few monitoring sites in the UK experienced 'Moderate' NO2 pollution levels, defined as concentrations exceeding 200 µg/m3. One such site was London's Marylebone Road, which recorded 853 hours of 'Moderate' or worse pollution in 2005 but no more than one hour per year from 2019 onwards.

Road transport is a major source of NO2 pollution in the UK, particularly in congested areas surrounded by tall buildings that prevent the dispersion of pollutants. Diesel cars produce more nitrogen oxide emissions than petrol cars, and the introduction of the Ultra Low Emission Zone (ULEZ) in London in April 2019 targeted these high-emitting vehicles. The ULEZ charges older diesel and petrol cars £12.50 per day to enter the zone, leading to a 20% reduction in road traffic emissions and significantly fewer polluting vehicles entering the zone.

The health impacts of NO2 pollution are significant. Short-term exposure to high concentrations can cause airway inflammation and increased susceptibility to respiratory infections, particularly for those with pre-existing lung or heart conditions. Long-term exposure is even more concerning, with an estimated 5,900 premature deaths in London in 2010 attributed to NO2. When combined with the effects of another pollutant, PM2.5, the total number of equivalent premature deaths in London that year rose to 9,400.

Frequently asked questions