Background Exposure to outdoor air pollution is a well‐established risk factor for a range of adverse health conditions. No previous study has quantified the extent to which children with intellectual disability (ID) may be exposed to outdoor air pollution.

Methods Secondary analysis of data extracted from the UK's Millennium Cohort Study, a nationally representative sample of over 18 000 UK children born 2000–2002.

Results Averaging across ages, children with IDs were 33% more likely to live in areas with high levels of diesel particulate matter, 30% more likely to live in areas with high levels of nitrogen dioxide, 30% more likely to live in areas with high levels of carbon monoxide and 17% more likely to live in areas with high levels of sulphur dioxide.