Scottish Air Quality Advisory Group advice note 2, March 2026
Expert advice from the Air Quality Advisory Group on the potential air quality impacts of policies within Scotland’s Climate Change Plan 2026 to 2040.
Are the draft CCP policies presented to the Group likely to make a significant contribution to further emissions and concentrations reductions for the main air pollutants of concern?
Taken together, the package of policies offers the potential to improve overall air quality. To assess this improvement objectively, it will be necessary to distinguish between progress towards achieving air quality standards and progress towards reducing the human health burden of air pollution, as well as environmental impacts on sensitive habitats and designated nature conservation sites (particularly from atmospheric nitrogen inputs), whilst at the same time mitigating any unintended disbenefits. There are also co-benefits that could be optimised further.
In order to better understand the health benefits, there should be a greater research focus on all air pollutants known to affect human health, together with the individual components of fine particulate matter and also on different size fractions, most importantly ultrafine particles (UFPs). The fact that the impacts of primary and secondary particulate matter (PM) emissions manifest at different scales (both temporally and spatially) is another factor to be considered. Given the technical complexities of monitoring particulate matter at very low concentrations, modelling will play an important role, also in predicting the impacts of different policy scenarios that alter emissions. Detailed modelling should be commissioned to assess not only the changes in air pollution, but the potential impact on health and the resulting health gains/losses as well as environmental impacts, for comparison with the cost implications of implementing the proposed climate change interventions.
Taking into account the transboundary contribution to PM concentrations in Scotland, the limits of what can be achieved by domestic policy and the importance of co-operation across the UK and Europe should be borne in mind. Caution should also be exercised in relying on climate change policies to deliver air quality benefits, as certainty of implementation cannot necessarily be guaranteed beyond the current political cycle.