The EU have passed a bill that makes the use of Particulate filters mandatory on new diesel cars from 2009. Exististing diesel cars will have to be retrofitted with particulate filters before January 2011.
Particulate matter have been found to cause Lung cancer, asthma and cardiovascular problems which can all result in premature death. It is aproximated that particulate matter kills somewhere between 20.000 and 50.000 people each year, in the US alone.
Particulate filters can remove as much as 99% of the particulate matter emmited by a diesel car.
Only 10% of all particulate matter comes from cars.