Tuesday, 1 February 2011

Chemistry 2: A rant at pseudo-science adverts

"The only toothpaste with liquid calcium to strengthen your teeth"
"When a car brakes, some of the energy it produces is lost"
"Anti-perspirant with silver molecules"
"Contains pro-oxylane to give your hair extra shine"

Don't get me started on pseudo-science in television adverts.  The voice-over begins, sounding professional, authentic and a leading authority on all things scientific.  The picture zooms in with hexagons flying around all over the place, and stick-and-ball-model molecules start being absorbed into your hair, skin and teeth.

What is it with the hexagons anyway?  Do these chemicals contain honey from a honeycomb?  Do the treatments contain a hexagonal molecule, like benzene (causes cancer, leukemia and is fatal if absorbed in even small doses) or cyclohexane, say (harmful if inhaled or swallowed)?  Perhaps "hexagons" means "scientifically clever", and not "very dangerous".  Still, just watch a TV advert for the latest shampoo or face cream and count the hexagons.  Double your score if the hexagons are gold-coloured or shiny.

Liquid calcium, featured recently in a toothpaste advert (and an advert which thankfully has not been seen recently) is an interesting concept.  Calcium is a metal, and as is generally know, metals have high melting points; in the case of calcium, you have to heat it up to 842 to 848°C in order to melt it.  Now, if toothpaste actually contains liquid calcium, I wouldn't want to put it in my mouth - in fact I wouldn't want to hold the toothpaste tube (and I wouldn't even want to contemplate squeezing the tube, which would have to be made of something other than the typical plastic material).  Still, I'm glad the advert was taken off air.  The truth (a strange concept for advertising, I accept) is that it will contain a calcium compound in an emulsion.  It's a bit like saying that the sea is liquid salt:  interesting, but patently untrue.  Actually, a closer comparison would be to say that the sea is liquid chlorine: dramatic and thankfully untrue.

Next:  silver molecules in anti-perspirant.  Yes, some anti-perspirants contain some molecules that contain a silver ion in a larger molecule.  Here's an example of one such anti-perspirant and for those paying attention, please note the shapes on the front of the can.  The advert for the anti-perspirant features a silver truncated icosahedron - another scientific shape that's not relevant here - that strongly suggests that the product contains a molecule composed entirely and uniquely of silver atoms.

Silver molecule?  Or just a football?

The truth about 'silver molecules' is much more prosaic; the compound in question is probably a variation of the molecule silver sulfadiazine, which, incidentally also contains sulphur - again, not something you'll hear in  advert.  Here's silver sulfadiazine - I figured it was time for a diagram with some genuine scientific basis.  The silver ion is shown by the Ag+ as the chemical symbol for silver is Ag (from the Latin argentum, which also provides the French argent).

Next time, I'll look at made-up scientific names - if only for the fun of it.  Pro-xylane, AHAs, nutrileum, pentapeptides and the rest of it.  In the meantime, should advertisers use proper science?  Probably not.  Will they?  No.  Why not?  Because they're not worth it.


  1. Ah but where would we be without Kryptonite

  2. @Tim - that's a good question. We'd probably better off, Superman would for sure, but I'm not telling him that I've got a pocketful!