The Cillit Bang commercials, created by JWT and styled like an informercial product demonstration, claimed the ability to turn old 1p coins shiny again and dissolve solid lumps of calcium.
Reckitt Benckiser claimed in the television spot "limescale is simply calcium that sticks. And if solid calcium dissolves this fast, imagine how Cillit Bang works on taps and sinks".
In the JWT ads, visuals show limescale on a sink and taps being sprayed with the product, which is then cleaned by a cloth, with on-screen text indicating that the spotless effect would be achieved in 15 seconds.
The Cillit Bang ads, the name for which comes from the Cillit crystal like bath salts or caustic soda, also show an old penny looking as good as new after a brush with Cillit Bang. A penny is held in a tank with the product as the presenter says: "Look how it gets this old penny as good as new."
The ad was criticised by 20 viewers for being misleading by claiming that calcium was so reactive it would dissolve as quickly in water as it did in Cillit Bang and also that limescale is made up of calcium compounds and was less reactive than calcium.
One viewer objected that the ad portrayed the product as a fast fighting cleaner, which in his experience was not the case, and five viewers believed it took longer than claimed to get a discoloured penny shiny and new looking.
The BACC thought that although the claims about limescale "were worded in a scientifically naive way", the demonstration was fine. However, the ASA upheld the complaint saying that the demonstration showed the dissolution of calcium carbonate, not calcium.
The watchdog found the advertiser substantiated the claim that Cillit Bang would effectively remove limescale in 15 seconds, however the evidence of before and after photographs to support the discoloured penny were not found to be adequate.
"We recognised that using the product on coins was unlikely to be what most viewers would use the product for. None the less, it was designed to give an impression of what the product could do and the evidence did not support what was an exaggerated claim," the ASA said.
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