The latest report on air pollutants in Scotland has been published by Scotland's Chief Statistician.

The main findings of the report include:

• Over the long term there have been reductions in emissions for all the pollutants.

• Since 1990, there have been decreases of 12 per cent for ammonia, 64 per cent for PM10, 65 per cent for NMVOCs, 67 per cent for PM2.5, 72 per cent for nitrogen oxides, 84 per cent for carbon monoxide, 94 per cent for sulphur dioxide and 98 per cent for lead. Between 2015 and 2016, there were reductions in emissions for 6 of the 8 pollutants (sulphur dioxide 34 per cent, nitrogen oxides 12 per cent).

• There were small increases in emissions of ammonia (+3 per cent) and NMVOCs (+1 per cent).


The 1990-2016 figures in this Statistics Release are from the NAEI report "Air Quality Pollutant Inventories for England, Scotland, Wales and Northern Ireland: 1990 – 2016", produced by Ricardo Energy and Environment for the Scottish Government, the UK Department for Environment, Food and Rural Affairs, the Welsh Assembly Government and the Northern Ireland Department of Environment.

Emissions from the offshore oil and gas exploration sector are not attributed to a specific country but are reported within an "unallocated" category.

There are uncertainties associated with all estimates of pollutant emissions. The uncertainty rating are "high" for PM10, PM2.5 and Lead, "moderate" for ammonia and carbon monoxide and "low" for nitrogen oxides, sulphur dioxide and NMVOCs. (Low refers to the uncertainty of a particular pollutant being relatively low when comparing to the other pollutants and vice versa). However, although for any given year considerable uncertainties may surround the emission estimates, it should be noted that trends over time are likely to be more reliable.

Air pollutant emissions are reviewed every year, and the whole historical data series is revised to incorporate methodological improvements and new data.