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Buttercups at Chilton site, Oxfordshire

Odours occur in outdoor and indoor environments originating from a variety of sources that can be man-made (e.g. industry) or from natural sources (e.g. plants, animals, volcanoes).

‘Odorants’ are the chemicals present in the atmosphere and the term ‘odour’ is used to describe how odorants are perceived when we smell them, e.g. pure hydrogen sulphide gas smells of rotten eggs. Odours are frequently made up of numerous compounds, e.g. the smell of ‘coffee’ comprises in the region of several hundred compounds and it is the combination of these compounds that we smell.

Odours can arise from regulated sources e.g. landfill sites, composting facilities, food processing and agriculture. These types of activities are regulated to ensure that significant releases of odour are not discharged into the environment. In England and Wales the Environment Agency regulates releases to air, including odour, from major industries whereas local authorities regulate the less polluting industries.

Odour Incidents

Odours can also be released into the atmosphere during incdents at regulated sites or during chemical spills or gas leaks.

  • If you believe that odour from a regulated site is causing an odour incident, please contact the Environment Agency or your local authority.
  • If you smell gas then contact the National Gas Emergency Services on 0800 111 999.
  • If you believe that you can smell an odour from a chemical spill or leak, please contact the emergency services on 999

Information for the public

General information for members of the public regarding exposure to chemical odours

Information for professionals

Information and guidance for professionals responding to incidents involving odours