Science Questions

What in WD40 kills spiders?

I caught a three inch long spider in my house with a special miniature vacuum cleaner designed to catch spiders. I didn’t know how to kill it so I coated it liberally with WD40. it took about five minutes to die, which I hope wasn’t too painful, so what was in the WD40 that killed it? James, Derby

Chris & Kat discussed this question in the studio with Ray Marriott...

Kat:  I think it’s probably blocked its breathing apparatus or something like that.  That’s a horrible thing to do. You should let it out, let it run free!

Chris:  Ray, what do you reckon?

Ray:  Probably a solvent which is actually carrying the penetrating oil probably asphyxiated it first and then it blocked its spiracles afterwards.

Chris:  Because most volatile things can act as general anaesthetics so when people inhale lighter fluid and things, they’re actually putting all that gas into their brain. It seems to cause brain cells to decrease their activity so it could be that it anaesthetised it and then, as you say, asphyxiated it.

Kat:  Maybe it died high as a kite?

Chris:  You never know.

October 2007