Air pollution more harmful to children in cars than outside, warns top scientist

Exclusive: Walking or cycling to school is better for children's health as cars are 'boxes collecting toxic gases' says David King

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Children are at risk of dangerous levels of air pollution in cars because exposure to toxic air is often far higher inside than outside vehicles, a former government chief scientific adviser has warned.

Prof Sir David King, writing for the Guardian, says walking or cycling to school would be much better for children's health. The warning comes as the UK government faces a third legal defeat for failing to tackle the country's illegal levels of air pollution. Air pollution is known to damage children's developing lungs but recent research also indicates it harms children's ability to learn at school and may damage their DNA.