The Greenest Countries: Leading The Way To Sustainability

Air pollution is a pressing issue, with 99% of the world's population living in areas where air quality exceeds World Health Organization (WHO) guidelines. It is a leading cause of non-communicable diseases, contributing to 16% of global deaths, and is responsible for more than 10% of all deaths worldwide. The most polluted countries are often poor, large countries with insufficient infrastructure to address air quality issues. Countries with the cleanest air are typically those with strong environmentally-friendly policies and initiatives, and some of the least polluted countries are small islands with relatively small populations. While it is difficult to definitively state which country causes the least pollution, this paragraph will explore some of the least polluted countries and their efforts to maintain clean air.

Island countries vs larger countries

The world's least polluted countries are a mix of countries and island nations. The top three least polluted countries are French Polynesia, Mauritius, and Iceland. These countries have low levels of PM2.5, but they are not the least populated areas on Earth. The least polluted areas are territories, which are islands with small populations.

Island countries face unique challenges when it comes to pollution, especially waste management. Due to their small size, limited disposal capacity, and high export costs, over 80% of mismanaged waste in small island developing states (SIDS) ends up in the ocean, according to UN reports. This leads to biodiversity loss, accelerated climate change, loss of tourism revenue, and health issues for the local population.

To address these issues, the UN Environment Programme (UNEP) and the Global Environment Facility (GEF) have launched the ISLANDS program, a $515 million initiative to help island countries prevent the release of toxic chemicals and marine litter. The program focuses on implementing sustainable, low-chemical development practices and includes participation from the private sector, with recycling training and increased access to global recycling markets.

When comparing island countries to larger countries, it is important to consider the differences in population size, industry, and infrastructure. Larger countries, especially those with emerging or developing economies, tend to have higher pollution levels due to larger populations, more vehicles, and older, less efficient technology. However, it is worth noting that larger countries may also have more resources and infrastructure to implement pollution control measures, such as investing in renewable energy projects, improving public transportation, and encouraging sustainable practices.

In summary, while island countries may have an advantage in terms of lower pollution levels due to their smaller populations and less industrialized economies, they also face unique challenges, such as waste management, that can have significant environmental and health impacts. Larger countries, on the other hand, often have higher pollution levels but may also have more resources to address these issues.

Territories with the least pollution

Air pollution is a critical global health problem, contributing to over 10% of worldwide deaths, with nearly 4.5 million premature deaths recorded in 2019. The World Health Organization (WHO) has set a target of 0-10 µg/m³ for air pollution, with a maximum of 5 µg/m³ for PM2.5 particles. However, only a handful of countries meet these guidelines.

The least polluted territories in the world are a mix of countries and island nations. As of 2023, the top three countries with the least air pollution are French Polynesia, Mauritius, and Iceland. These nations boast impressive air quality, with low levels of PM2.5 particles. Other territories with notably low pollution levels include Grenada, Bermuda, and Puerto Rico.

In 2025, a study by IQAir revealed that only seven countries met the WHO guidelines for PM2.5 particles. These countries included Australia, New Zealand, Estonia, Iceland, and some small island states. Notably, Estonia, Finland, and Sweden were also recognised for their higher air quality compared to other European countries.

While these territories have the least pollution, it is important to acknowledge that even small amounts of air pollution can have adverse health effects. Additionally, the impact of pollution extends beyond the numbers, affecting the environment and ecosystems. As such, territories with low pollution levels should not become complacent but continue to strive for even better air quality and environmentally friendly initiatives.

Countries with strong environmentally-friendly policies

While the world's least polluted countries are a mix of countries and island nations, with French Polynesia, Mauritius, and Iceland topping the list, it is important to acknowledge that some of these countries contribute to detrimental air quality in other places.

Switzerland

Switzerland has been ranked as the most sustainable country in the world and is regarded as one of the most eco-friendly countries globally. The country has high environmental health, sustainability, water sanitation, and water resources. Switzerland's public sector increasingly demands eco-friendly and resource-friendly products, and it is one of the top recyclers in the world. The country has strongly embraced renewable energy, with its largest transportation company, SBB, relying on electric trains—and, as of 2023, 90% of the trains’ electricity was generated via hydropower plants. Switzerland's Environmental Performance Index (EPI) score in 2022 was 81.5, placing it among the top countries globally.

Germany

Germany is a leader in environmental conservation and has some of the world's most efficient policies to reduce greenhouse gas emissions and prevent climate change. The country has an ambitious "Energiewende" (energy transition) policy, aiming to shift from fossil fuels to renewable energy sources. In 2020, renewable energy contributed to 46% of electricity consumption in Germany, and the country has invested tremendously in solar and wind power. Germany also has a robust recycling system, with 67% of recycled materials, considered one of the highest in the world.

Denmark

Denmark has been ranked as the most environmentally friendly country in the world, with high scores in almost all issues tracked by the EPI. The country stands out for its efforts in clean energy and sustainable agriculture, and it is one of the few countries on schedule to reduce net CO2 emissions to zero by 2050. Denmark also actively participates in protecting natural resources and promoting the sustainable use of the Earth's resources, with a strategic development vision for wind energy.

Sweden

Sweden has been a significant player in eco-friendliness, with a clear vision for a greener economy and sustainability. The country has set goals to reduce greenhouse gas emissions to zero by 2045, and more than 54% of its energy is generated from renewable sources, including wind, hydropower, and bioenergy. Sweden has a robust recycling system, with 98.7% of household waste being recycled or used for energy generation.

United Kingdom

The United Kingdom has the second-highest EPI score in the world, and between 2012 and 2022, it made the third-highest improvement of any country. The UK is also on schedule to reduce its net CO2 emissions to zero by 2050 and has posted perfect scores for sanitation and drinking water. The country also scores high for its management of solid household fuels and soil acidification.

The impact of war on air quality

The world's least-polluted countries are a mix of island nations and territories with relatively small populations. These include French Polynesia, Mauritius, and Iceland. However, it is important to note that even these countries may contribute to poor air quality in other regions.

War and armed conflict have devastating impacts on the environment and air quality. The use of nuclear weapons, for example, releases radioactive particles that contaminate land and water, as seen in Hiroshima and Nagasaki during World War II. Similarly, the 1991 Gulf War resulted in Kuwaiti oil fires due to the scorched earth policy employed by retreating Iraqi forces.

In the 21st century, conflicts such as the Russia-Ukraine war have highlighted the detrimental effects of war on air quality. The burning of human waste, munitions, plastics, and other chemicals in open pits during military engagements can release toxic smoke, impacting both military personnel and civilians. War activities in Ukraine led to an average increase of approximately 9.78% in PM2.5 and 10.07% in NO2, which are harmful pollutants. Additionally, the displacement of people during wars can put pressure on the surrounding ecosystem, leading to deforestation and degradation of natural resources.

The Afghanistan conflict, from the Soviet-Afghan War to the recent US withdrawal, has adversely affected the health of civilians and veterans, infrastructure, and social structures. The open-air burn pits used by the US Department of Defense produced hazardous emissions linked to chronic illnesses and even fatalities.

Overall, war has severe consequences for air quality and the environment, causing pollution, ecosystem disruption, and long-term health issues for affected populations.

The impact of tourism on air pollution

While the world's least-polluted countries are a mix of island nations and territories, such as French Polynesia, Mauritius, and Iceland, it's important to acknowledge that these countries can still contribute to detrimental air quality in other regions. The impact of tourism on air pollution is a complex issue that has been explored in various studies.

Several studies have found a significant relationship between tourism development and air pollution, particularly in terms of increased energy consumption, CO2 emissions, and other air pollutants. For instance, research on the Environmental Kuznets Curve (EKC) hypothesis and tourism-induced effects on PM2.5 emissions in China revealed that tourism's impact on air pollution varies depending on the mode of tourist arrivals and the geographical scale examined. At the national level, tourism's effect on PM2.5 emissions followed an inverted-U shape, while in eastern China, it exhibited a U-shaped impact.

While tourism can contribute to increased air pollution, it is essential to consider the modes of transportation and energy sources utilized by the tourism industry. For example, the adoption of renewable energy sources and sustainable practices within the tourism sector can help mitigate the environmental impact. Additionally, local governments can play a crucial role in monitoring and improving air quality, ensuring that tourism development is balanced with environmental considerations.

In summary, the impact of tourism on air pollution is multifaceted and varies across different regions and scales. While tourism can lead to increased energy consumption and emissions, it is also important to consider the economic benefits it brings to local communities. By addressing air quality issues and implementing sustainable practices, the negative impacts of tourism on the environment can be mitigated, contributing to a more positive overall effect on the region.

Frequently asked questions