UCL Faculty of Laws


Professor Eloise Scotford co-authors UNEP guide helping countries tackle harmful air pollution

7 September 2023

The report, 'Guide on Ambient Air Quality Legislation’, aims to give policymakers the legal and governance tools to improve air quality governance.

Eloise Scotford

A new United Nations Environment Programme (UNEP) report - an interdisciplinary collaboration between two lawyers, Professor Eloise Scotford (Dean of UCL Laws) and Professor Delphine Misonne (Université Saint-Louis Brussels, and atmospheric scientist Professor Alastair Lewis (University of York) - aims to help countries to create the legal and governance frameworks that are needed to address harmful levels of air pollution.

Air pollution, identified by the World Health Organisation (WHO) as the world’s largest environmental health risk, is estimated to have caused 4.2 million premature deaths globally in 2019.

A previous UNEP report – also co-authored by Professor Scotford – found significant gaps in most countries’ governance of outdoor air quality. For instance, only 33% of countries imposed obligations on institutions to meet legally mandated standards – a key feature of effective air pollution governance.

The ‘Guide on Ambient Air Quality Legislation’ aims to give policymakers the legal and governance tools to improve air quality governance, with a checklist of questions to consider and case studies of frameworks from around the world.

Professor Scotford said: “For a long time, air pollution has been seen as a scientific and technical problem. However, it is now increasingly understood as a problem of policy and governance.

“Addressing air pollution in a meaningful and long-term way requires a co-ordinated response cutting across policy areas and government departments – it must be a collective endeavour in the same way as tackling climate change. The goal of clean air has to be embedded throughout the administrative and legal landscape.

“This latest report provides a blueprint for everything policymakers need to consider in order to build an air quality governance system that promotes clean air for all – a fundamental public good.”

Co-author Professor Delphine Misonne said: “Ambient air quality standards are not self-executing; they must be legally constructed within national systems and the new report is meant to literally guide towards more robust systems of air quality governance.” 

The guide does not recommend specific legislation to be adopted by all countries, as legal contexts and the types and levels of pollution vary widely. Countries may have high or low levels, and may need to address pollution caused by natural events such as forest fires and dust storms, or pollution originating from beyond their borders.

A core feature of air quality governance is ambient air quality standards, which set a value for a minimum acceptable quality of outdoor air. To be effective, the guide says, these standards must be “embedded within a comprehensive legal architecture”, with mechanisms for monitoring, accountability and enforcement.

Questions for policymakers to consider include “Are air quality laws drafted in such a way that they are enforceable?” and “Is there a clear delineation of government responsibility for monitoring?”

The guide notes that a minimum acceptable standard of air quality on its own risks sanctioning pollution under a certain level and legislation should include “processes for moving towards a higher level of ambition over time”.

For countries with currently high levels of air pollution, the guide says, “legal frameworks for phased improvement of air quality will likely be important.”  

The earlier 2021 UNEP report, entitled “Regulating Air Quality: The first global assessment of air pollution legislation”, found that:

  • In at least 34% of countries, ambient air quality was not yet legally protected.
  • Institutional responsibility for attaining standards was weak globally – only 33% of countries imposed obligations to meet legally mandated standards.
  • Monitoring, critical to knowing if standards are being attained, was not legally required in at least 37% of countries.
  • Although air pollution knows no borders, only 31% of countries had legal mechanisms to address cross border air pollution.

In 2022, the United Nations declared that a clean, healthy and sustainable environment was a universal human right, with explicit recognition of the potential role of air pollution in interfering with this right.