Rotenone - the active ingredient obtained from the crushed root of the derris tree - has been linked to the progressive brain disorder Parkinson's disease, and a subsequent investigation by the Pesticide Safety Directive (PSD) has led to the decision to withdraw all derris-based sprays and powders.
All I know is that my father made frequent use of this 'natural' pesticide and did indeed develop Parkinsons in his late seventies, and subsequently died from the disease.
I would suggest there are better ways to control pests without the danger.

I have bio liquid derris plus, 8g/L Rotenone.
It says 5ml to 1.1 Litres.

All insecticides if used incorrectly I guess would have the potential to cause harm, but on the bit of evidence on rats being injected with it I would have no qualms about using up what I have left.

Depends on how we define 'incorrectly'. It's interesting how what is 'safe' one year is unsafe under new regulations a year later. Most of the common pesticides that were used by gardeners from Victorian times onwards are now banned because of what we now know.
What is important is to balance what you want to achieve in your garden against the possible risks to health. As there are many organically safe methods to use in controlling pests, all I question is whether it is a good idea to use something where considerable evidence suggests a lot of harm can result to the user.

Politics is probably the best answer as to what is safe one year but not the next. Derris was not banned for health reasons, it was a licensing thing, ie, the cost of re licensing wasn't worth it.
So it's because of the EU that the older products aren't available to the average gardener. They are still available commercially in a more potent form.

All the same I guess Bertiefox won't be using it!

I think that's a banker bet.

It's up to soobydoo what he/she does with the information given.
I like to vary insecticides, (not on veg as I don't use anything on them unless absolutely essential and then it would be something simple) to prevent resistance building up. Thanks to the EU that is becoming increasingly difficult for the average gardener.

Malathion is another example, available in America but not here. Yet half the population under the age of 10 have probably used it on their head at least once.