Air pollution is damaging the environment and is a significant determinant of human health. The UK is currently failing to comply with EU law that sets out limits for air pollution, and few countries perform as poorly as the UK in terms of the number of areas that are non-compliant, and the length of time this is likely to remain the case. Without major policy changes, most of the UK will remain in breach of legal limits for air pollution into 2025 and beyond.
Here is the report from IPPR, followed by their own summary:

In this briefing, we set out why the scale of the air pollution problem in the UK requires a bolder and more holistic approach, which involves moving away from diesel vehicles (in favour of petrol and, ultimately, hybrid and electric alternatives), as well as a shift from private car ownership to car sharing schemes, public transport, walking and cycling. Not only could these shifts save thousands of lives, they could also drive improvements in two of the government’s other transport objectives: a reduction in congestion, and a reduction in road-based CO2 emissions.