Main content
![](https://ichef.bbci.co.uk/images/ic/640x360/p01lcr93.jpg)
Suspect
A scientist is convinced that leaks from a chemicals plant are responsible for an increase in childhood asthma, but he receives an anonymous threat to keep quiet.
Last on
Sat 16 Feb 2008
13:30
Broadcast
- Sat 16 Feb 2008 13:30