I got a bizarre email (actually about three years ago, and then again this morning, from different people) of the kind that propagates urban legends and potentially dangerous chemical disinformation. The email claims that well-known greasy spray lubricant and foe of water and rust WD40 is mainly fish oil. Of course, it is not fish oil, it’s a petrochemical product, the fish oil link is one of those stupid urban legends that do the rounds periodically.
The safety data sheet has the full skinny on WD40 here: http://www.wd40company.com/files/pdf/msds-wd494716385.pdf
It boils down to WD40 being mostly mineral oils and solvents (hexane), it’s a bit like a lighter version of gasoline or petrol, in other words.
The email had a long list of about 43 household tips for using WD40 around the home. The manufacturer, however, does not recommend its use for about half of those “tips”. WD40 is for the workshop, not the kitchen (unless you’re lubricating a cookerhood fan or something).
WD40 really is not something you should be splashing around the house just because some random email tells you to. Breathing it in can cause pneumonitis, lung damage and in extreme cases can kill. Admittedly, effects are dose dependent (they always are), but as a chemist, I hate this kind of chemical disinformation, it can be seriously dangerous.
Thankfully not listed is the tip that WD40 is good for arthritis, it’s not, any repeated application to your skin is likely to give you contact dermatitis, which you really don’t want.