Liberal Democrat Manifesto: Environment

Published: 26th May 2017

“Air pollution in the UK is a killer. It contributes to 40,000 premature deaths a year and costs the NHS £15 billion.”

The number of premature deaths each year in which outdoor air pollution is a contributory factor is generally (although not universally) agreed to be around 40,000. As we’ve pointed out previously, that doesn’t mean that this number of people actually die prematurely every year because of air pollution, as it’s not the sole cause of deaths. Decreasing air pollution won’t prevent deaths, but it will increase longevity.

The cost to human health

  • A much-quoted report from the Royal College of Physicians and Royal College of Paediatrics and Child Health in February 2016 put the number of premature deaths in the UK linked to air pollution at 40,000.
  • The science behind the report is complex, and the findings have been challenged. In particular, it doesn’t mean that air pollution literally causes 40,000 deaths a year.
  • As the Committee on the Medical Effects of Air Pollutants has said previously: "it should not be interpreted as the number of individuals whose length of life has been shortened by air pollution, as this would only be true if air pollution were the sole cause of deaths. Rather, it is an estimate of the total mortality effect in the local population".
  • What this means is that air pollution makes a small contribution to those deaths. It’s  linked to a number of health problems, including cancer, asthma, strokes and heart disease.
  • Greenpeace quotes one expert as saying that the data going into the study has been “overinterpreted” and that “the basic data does not say that 40,000 people have died ... There is loss of life from air pollution but the discussion of deaths isn’t helpful”.  

We also checked the same claim in the Green party manifesto.

Costs to the NHS and the economy

  • Identifying and putting a figure on the health costs of air pollution isn’t straightforward either and there are no official estimates for the cost to the NHS - yet.
  • The estimates we do have (which may be calculated in different ways) generally take a broad view of the health and social costs of air pollution, going beyond the cost to the NHS. They vary quite widely.
  • The Liberal Democrats took their figure from a 2010 Department for Environment, Food and Rural Affairs report, which said that “air pollution causes annual health costs of roughly £15 billion to UK citizens”. A more recent (September 2015) version of this estimate is over £16 billion.
  • The report from the RCP and RCPCH estimated the social cost of air pollution from NO2 and particulates - the costs to health services and to business - at around £22.6 billion.
  • The World Health Organisation estimated that indoor and outdoor air pollution cost the UK 3.7% of GDP in 2010, or US$ 83 billion (£54 billion at the time).

Update 2 June 2017

We've added content on the cost to human health, and we've now written about this in our Green manifesto roundup as well.

This factcheck is part of a roundup of Liberal Democrat party manifesto launch. Read the roundup.

Liberal Democrat manifesto launch, factchecked

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