Pollution levels drop by two thirds

Levels of several major air pollutants in Scotland have dropped by more than two thirds since 1990, new figures show.

The largest drop was recorded in lead, which fell by 99 per cent between 1990 and 2015, followed by a 92 per cent drop in sulphur dioxide over the same period, and an 83 per cent fall in carbon monoxide.

Nitrogen oxide levels are down 71 per cent over the 25 years and a group of chemicals called nonmethane volatile organic compounds (NMVOCS), which include benzene, ethanol and formaldehyde, have dropped 66 per cent. The level of tiny particles of pollutants known as PM10 has fallen 63 per cent.

Ammonia has fallen the least since 1990, with a 10 per cent drop.

The latest figures in the National Atmospheric Emissions Inventory report to 2015 showed little change from the previous year - ammonia increased from 36 to 37 kilotonnes (kt) in that period, while carbon monoxide dropped from 113kt to 112kt and nitrogen oxides fell by 4kt to 84kt, driven by improvements in the energy industries.

Sulphur dioxide showed the largest change year on year, falling from 30kt to 23kt, also due to a drop in energy industries.