Air pollution - health impacts: summary research findings

1 Background

The scope of the work commissioned under this specific request arises from the Cleaner Air for Scotland 2 (CAFS2) Strategy. One of the actions from the CAFS2 Strategy is to assess the evidence on health impacts of low-level air pollution in countries with levels of ambient concentrations comparable to Scotland. To review and assess the evidence of health impacts in such countries, a robust, rapid semi-systematic literature review was undertaken. This review aims to collate and discuss the evidence on:

• The health impacts of air pollution at low levels comparable to Scotland
• Reasons for an absence of association between air pollution and cardiovascular disease in Scottish studies.

This review covers research published between 1 January 2020 and 1 January 2024^[1] and builds on a mapping review by Dominski et al. (2021) ‘Effects of air pollution on health: A mapping review of systematic reviews and meta-analyses’, herein referred to as the Dominski review. To define countries as comparable to Scotland, data on the population-weighted mean exposure in either 2017, 2018 or 2019 (pre-COVID-19) was collected with a PM_2.5 annual mean threshold of 12 µg/m³, as the United Kingdom (including Scotland) mean is approximately 10.2 µg/m³ (based on the State of Global Air 2017-2019 data) (Health Effects Institute, 2020).

This report presents a summary of the research findings from this review. For further detail on the methodology, including the search terms and limits, please see RESAS/020/20 – Final Report.