Sweden's Air Pollution: Causes And Concerns

Air pollution is a pressing issue in Sweden, causing an estimated 6,700 premature deaths annually. While the country enjoys relatively good air quality compared to other European nations, certain areas, particularly urban centres, experience elevated levels of harmful pollutants. These pollutants, primarily nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5), are largely attributed to traffic emissions, energy production, and industrial activities. Sweden has implemented various measures to tackle air pollution, including emission reduction incentives and the development of sustainable infrastructure, reflecting its commitment to mitigating the health and environmental impacts associated with poor air quality.

Traffic, industry, and wood burning

Sweden has enjoyed high-quality air since 2019, achieving the World Health Organisation's (WHO) target figure of 10 µg/m³. However, air pollution remains a concern, especially in urban areas, where traffic, industry, and wood burning are significant contributors.

Traffic, particularly in busy cities like Gothenburg, is a major source of air pollution in Sweden. The city's central location and large port mean that vehicles travelling to and from the port pass through low-lying areas, emitting high levels of nitrogen dioxide (NO2) from their diesel engines. Similar issues are observed in Sundsvall, which is situated between two mountains, trapping polluted air and causing it to stagnate.

The Swedish Environmental Protection Agency has reported a sharp decline in emissions of sulphur dioxide (SO2), nitrogen oxides (NOx), volatile organic compounds (VOCs), particulate matter (PM2.5 and PM10), and heavy metals since 1990. However, the rate of decline has slowed in recent years, and certain areas, such as Gothenburg, Södertälje, and Visby, continue to struggle with air pollution.

Industry and energy production also play a role in Sweden's air pollution. While the country has made strides toward carbon-negative energy production, such as Stockholm's target for a positive carbon footprint by 2040, the combustion and industrial emissions that contribute to fine particulate matter and nitrogen dioxide levels remain a challenge.

Wood burning, particularly small-scale burning, is another source of air pollution in Sweden. During the cold winter months, the combination of combustion and the use of studded tires can lead to increased levels of harmful particles and ground-level ozone.

Addressing these issues is a priority for Sweden, with initiatives such as the Swedish National Environmental Quality Objectives, which include the goal of clean air to protect human health, animals, plants, and cultural assets. Continuous monitoring, emission reduction strategies, and the transition to electric vehicles are all part of the country's efforts to improve air quality.

High levels of nitrogen dioxide

Sweden has been concerned about air pollution since the 1970s, and the country has one of the National Environmental Quality Objectives to maintain 'Clean air'. However, air pollution still poses a significant threat to human health, with over 5,000 people dying prematurely each year due to air pollution in Sweden.

One of the main causes of air pollution in Sweden is high levels of nitrogen dioxide (NO2). This is largely due to local traffic emissions, especially from diesel vehicles, which account for a large proportion of the vehicles on the road. The problem is particularly acute in Gothenburg, which has the largest port in Scandinavia. As a result, a significant number of vehicles travel through the low-lying central areas of the city, emitting large amounts of nitrogen dioxide from their diesel engines. The city's topography, surrounded by hills and ridges, also creates conditions for stagnant air, allowing air pollutants to accumulate rather than being vented away. This has led to Gothenburg exceeding the limit value for nitrogen dioxide for 21 days.

Stockholm, the capital of Sweden, has also struggled with high levels of nitrogen dioxide, exceeding the limit value for 29 days. Similar to Gothenburg, the high levels in Stockholm are attributed to road traffic, specifically emissions from diesel vehicles, heavy traffic volume, and queuing. The introduction of a congestion tax and environmental zones has been implemented to address the issue.

To combat the issue of high nitrogen dioxide levels across the country, Sweden has introduced fuel and purification equipment requirements, reduced the use of studded tires, and implemented a ban on studded tires in certain areas. These measures, combined with the increasing adoption of electric and hybrid cars, have contributed to a decrease in nitrogen dioxide emissions from passenger cars.

Despite these challenges, Sweden's air quality has improved over the last two decades, and the country continues to work towards meeting the World Health Organization's targets for air quality.

Particulate matter

Sweden has a strong commitment to clean air, with the Swedish National Environmental Quality Objectives stating that the air should be clean enough to pose no risk to human health, animals, plants, or cultural assets. The country has made significant progress in improving air quality over the last two decades, and its air quality is among the best in Europe. However, air pollution remains a concern, with an estimated 6,700 premature deaths occurring in Sweden each year due to poor air quality.

Traffic, especially diesel vehicles, is a major source of particulate matter in Sweden. The combustion of diesel fuel and the wear and tear on roads contribute to the presence of particulate matter in the air. Additionally, the use of studded tires in the spring can resuspend particulate matter, increasing its concentration in the air. To address this issue, Sweden has implemented a ban on studded tires in certain areas to reduce particle levels in the air.

Industry is another contributor to particulate matter in Sweden. Emissions from combustion and industrial processes can contain high levels of particulate matter, which can travel long distances and affect air quality in Swedish cities. While large combustion plants have effective emission reduction strategies in place, smaller plants may lack the necessary technology for continuous monitoring and reduction of emissions.

To combat particulate matter and improve air quality, Sweden has introduced equipment requirements and fuel standards. Additionally, the country is promoting the use of electric vehicles and carbon-negative energy production, with Stockholm aiming for a positive carbon footprint by 2040. These initiatives demonstrate Sweden's commitment to reducing particulate matter and improving the health and well-being of its citizens.

Ground-level ozone

Ozone at ground level is particularly harmful to children, the elderly, and people of all ages with lung diseases such as asthma. It can trigger a variety of health problems and is one of the six common air pollutants identified in the Clean Air Act. While ozone in the upper atmosphere forms a protective layer that shields us from the sun's harmful ultraviolet rays, ground-level ozone contributes to poor air quality and can cause serious health issues.

In Sweden, emissions of NOx, VOCs, and other air pollutants have fallen sharply since 1990, resulting in improved air quality over the last two decades. However, certain areas of the country, such as Gothenburg and Sundsvall, still struggle with high levels of NOx and PM10, which can be attributed to busy traffic routes, diesel engines, and the use of studded tires. To address these issues, Sweden has implemented measures such as environmental zones for heavy traffic, bans on studded tires in certain areas, and the introduction of fuel and purification equipment requirements.

The Swedish government is actively working to reduce ground-level ozone and other short-lived climate pollutants through initiatives like the Climate and Clean Air Coalition. They have provided funding to the Coalition's secretariat and the UNEP's fund to finance programs aimed at reducing these pollutants. Additionally, Sweden is home to innovative companies like Ozoneair, which specializes in ozone cleaning and offers high-quality purification products for various spaces, including houses, apartments, and vehicles.

While Sweden has made significant progress in improving air quality and reducing ground-level ozone, continuous efforts are needed to ensure that air pollution levels do not pose risks to human health and the environment.

Sulphur dioxide emissions

Sweden has enjoyed high-quality air in recent years, with the country achieving the World Health Organisation's (WHO) target figure of 10 µg/m³ in 2019. However, air pollution remains a concern, with certain pollutants, including sulphur dioxide (SO2), posing risks to human health and the environment.

The acidifying effect of sulphur dioxide can harm plants and animals, both terrestrial and aquatic. Acidification leads to the leaching of essential nutrients from the soil, potentially hindering forest growth. It also results in the release of metals into the ground, which can be harmful to decomposing organisms, birds, and mammals higher up in the food chain.

Additionally, sulphur dioxide emissions can have direct impacts on human health. Increased concentrations of SO2 in the air have been associated with a rise in hospital visits for heart disease and an increase in the number of deaths. SO2 can affect the respiratory tract and lung function and cause eye irritation. Recognising these health risks, Sweden has implemented SO2 policy instruments aimed at reducing emissions and mitigating their environmental and health impacts.

Despite these efforts, sulphur dioxide emissions remain a challenge. The complexity of various overlapping factors makes it difficult to attribute the reduction in emissions to specific policy instruments. As a result, additional measures may be required to address the issue effectively and ensure that Sweden meets its SO2-related environmental policy targets.

Frequently asked questions