Complete and utter rubbish, I’m afraid. I use this kind of thing every day. There are so many Health and Safety regulations in the entertainment industry and the fluid used in smoke and haze machines is very tightly controlled. Linseed oil is NEVER used, and if it was it would burn on the element and clog up straight away – the result would be very nasty when inhaled – and possibly truly dangerous. Burnt oil is nasty stuff. Linseed also stinks. Most modern smoke fluid is water based and usually glycol based. It does of course eventually settle and leave a slimy layer on the things it lands on, however, this is after weeks of intensive use.
You won’t find any major problems on your camera and lens – the fluid is quite neutral – after all as has been said, it isn’t uncommon nowadays, and if it damaged the kit – you’d have heard about it by now.
