What is SPRI?

The Scottish Pollutant Release Inventory (SPRI) is a publicly accessible electronic database of releases of pollutants to all environmental media and transfers of waste that will:

  • deliver the system by which Scotland will comply with the requirements of a Community Regulation on the implementation of a European Pollutant Release and Transfer Register;

  • help facilitate discussion and public participation in environmental matters and decision making;

  • aid delivery of data for policy makers, academics and the public;

  • support the prevention and reduction of pollution;

  • allow comparison of releases within industry and with other types of releases in Scotland, the UK and Europe e.g. road traffic and domestic heating, where such data is available; and

  • provide generic information on the pollutants.

SEPA intends that as far as practicable the Pollutant Release Inventory be the principle means by which information on Scottish pollutant releases and waste transfers is collected and made public. Wherever possible such information will be collected and presented by this one system.

SEPA also intends that it will, as appropriate, consult and inform in advance those required to submit information and to provide guidance on the requirements of the system. It is recognised that the requirements for information to be collected may be changed from time to time due to the addition or removal of pollutants or changes to reporting thresholds etc as more information becomes available or European reporting requirements change.

Within the UK, SPRI provides data to the National Atmospheric Emissions Inventory (NAEI) and the UK Pollutant Release and Transfer Register. Internationally, the data is also used to fulfil the reporting requirements of several treaties, obligations and conventions, for example, the Kyoto Protocol, the European Pollutant Release and Transfer Register (E-PRTR) and the Large Combustion Plant Directive. Most European and many international countries have similar databases (see links) to SPRI allowing comparison of Scottish data at the international level.

How to use SPRI

For members of the public the best use of SPRI is to find out what industrial activities are operating in your area (postcode or map search). This will enable you to see what pollutants are being released by industry in your area. It will also help you ask informed questions of the operator and SEPA. Please note that these releases are mass emissions and not concentrations. Therefore, they cannot be directly linked to health, air or water quality standards. SEPA regulates these releases ensuring they are within health and environmental standards.

Another use of SPRI data is to see if the releases are going up or down over time, for example, in the green house gas pollutants. However, these releases often fluctuate from year to year as industrial output fluctuates with demand for the product. Improvements or degradation in the efficiency of releases may be masked by production related fluctuations. For example, between 1996 and 2006, Scottish power plant emissions of sulphur dioxide decreased by 45% and emissions of nitrogen oxides increased by 2%. The trend for sulphur dioxide is negative between 1996 and 2006 because of the introduction of desulphurisation equipment on many of the power stations since 1996. Releases of nitrogen oxides decreased by 27% between 1996-2005 only to sharply rise by 40% in 2006. This large increase was due largely to the increased use of coal instead of gas. There are two main reasons for this phenomenon, the high price of gas in 2006 made coal cheaper to use and the closure of two UK nuclear power stations switched the demand to other non-nuclear plants. Sulphur dioxide emissions increased in 2006 by 22% for the same reasons. The price of gas is expected to remain high for the next couple of years so it is likely that nitrogen oxides and sulphur dioxide emissions will maintain their 2006 levels for the next couple of years. Indeed, given the current trend in oil and gas prices it is possible that emissions will continue to rise over the next couple of years.

Who has to report? (SPRI Activities)

Operators of certain activities above specified capacity thresholds are obliged to report to SPRI. There are 67 activities covering 10 major sectors that must report to SPRI. The activities and thresholds are largely determined by European reporting requirements but some thresholds have been lowered to be relevant to pollutant releases in the UK and Scotland. Below is a brief summary of the SPRI activities and thresholds:

  • All marine caged fish farms (no capacity limit). There can be up to 400 sites reporting;

  • All nuclear installations (includes plants undergoing decommissioning) and all non-nuclear installations holding or using open radioactive sources and disposing of radioactive waste. There area about 10 nuclear installations and 170 non-nuclear sites;

  • Municipal sewage treatment works with a design population equivalent of 15,000 population equivalent or greater (where population equivalent has the meaning given in the Urban Waste Water Treatment (Scotland) Regulations). There are about 70 sites reporting;

  • All industrial wastewater treatment plants with a capacity to treat at least 10,000m3/d

  • All Part A processes and thresholds defined in the Pollution Prevention and Control (Scotland) Regulations. These are the bigger industrial activities covering the energy, mineral, metal, chemical, waste management, food and drink, pulp and paper and intensive farming sectors. There are some Part B sectors included, for example, treatment of timber. There are about 450 sites reporting;

  • All sites having a waste management licence with a capacity to accept at least 50 tonnes/day of non-hazardous waste where the waste is destined for recovery or disposal.

The number of sites varies year to year due to sites closing or new ones opening. Some sites, like the marine fish farms, do not operate every year so will not return data for any years they do not operate.

There are changes at sites that can lead to a significant change in future data returns from previous data returns including:

  • Existing sites merging (for example due to a company takeover) and perhaps changing name.
  • An existing site has been split into two separate sites, run by two different operators (for example due to a company selling part of its business), with one or both sites changing names. 


The most notable impact of these types of changes in SPRI will be noticed in the amounts of waste transferred, the number of pollutants and the magnitude of their releases, in the most recent returns reported and compared to previous returns. This is called a “step change”. In these cases SPRI will maintain a history of the changes and the details are held in the "Voluntary Information" Section G of the site’s return data (only available to the operator making the return).

The releases and transfers data reported by the “new” site(s) may be notably different from the previous returns because of changes to the site. For example, a new site that resulted in a merging of two sites may report twice the release of carbon dioxide than reported previously by the individual sites. This does not represent a doubling in releases from one site but the summation of the two releases from the historically separate sites.

What information is reported?

In general, 215 pollutants to air, water, sewer and land are reported. Further off-site transfers of waste are also reported. Reporting thresholds are set to capture 95% of all industrial pollutant releases in the UK. SPRI reporting requirements have changed over the years to keep pace with the changes in European reporting requirements. Details of the current reporting requirements can be found here pdf link (353k).