Legal target: cut exposure by 30% from 2018 by 2030, and by 35% by 2040. The straight path needed 8.32 µg/m³ by now.

What it means: PM2.5 are tiny particles from burning fuel and wood, vehicle brakes and tyres, and farming. They are the air pollutant most harmful to health. The measure averages concentrations across England, weighted by where people live. A falling line is good.

Source: Defra, air quality statistics: PM2.5 targets; Environment Act targets set in 2023.