主播大秀

Ella was only 9 years old when paramedics were unable to resuscitate her following an asthma attack.

Her mum Rosamund says she was an incredibly healthy child, and believes the sudden on set of severe asthma was due to the poor air quality from pollution from diesel engines.

5 live Investigates has found that thousands of diesel cars have had their pollution filters removed, and the test designed to catch them doesn't work.

Rosamund pleads with diesel drivers to make sure their filters are properly installed, saying "please try and think of the damage it is doing to young people".

A spokesman for the Driver and Vehicle Standards Agency said it planned to introduce changes which would make the tests more effective in May next year.

This clip is taken from 5 live Investigates: Diesel Filters on Sunday 29th October 2017.