WQ98434 (e) Tabled on 20/03/2026

Will the Cabinet Secretary explain the rationale for reducing annual mean concentrations of fine particulate matter (PM2.5) air quality targets in ambient air to a level of 10 micrograms per cubic metre by 31 December 2035, rather than World Health Organization air quality guidelines of 5 micrograms per cubic metre?

Answered by Deputy First Minister and Cabinet Secretary for Climate Change and Rural Affairs | Answered on 27/03/2026

Welsh Government consulted on proposed PM2.5 target regulations from 17 November 2025 to 16 February 2026. Under the Environment (Air Quality and Soundscapes) (Wales) Act 2024, statutory targets must be achievable and Welsh Ministers must have regard to independent expert advice, scientific knowledge and WHO air quality guidelines. WHO guidelines are health‑based and not legal standards, as they do not consider feasibility or cost, but they have been used as benchmarks in developing the target proposals.

The proposals consulted on are supported by independent expert advice and a technical assessment of feasible air quality scenarios for Wales to 2040. The proposed target represents the lowest level, and earliest date, assessed as achievable. The proposed targets cut the allowed annual mean level for PM2.5 by more than half, aligning more closely with World Health Organisation recommendations.