An ad campaign by the US cotton industry has been banned by the Advertising Standards Authority for making misleading claims promoting the material as an environmentally-friendly product.

The campaign, for the Cotton Council International trading as Cotton USA, consisted of a magazine and poster ad. The ad used the line "Soft, sensual and sustainable, it's Cotton USA!".

Advertising regulators received three complaints challenging the term "sustainable", arguing that cotton is a "pesticide- and insecticide-intensive crop" that could "seriously deplete" groundwater supplies where it is grown in the US.

However, CCI argued that US cotton production met "reasonable and generally accepted" definitions of sustainability.

The organisation quoted definitions given by the United Nations, the US Environmental Protection Agency and the US Congress arguing that in each the "basic principles" were the same: economic viability, protection for the environment and social responsibility.

CCI said that pesticides today were "more targeted, less toxic and less persistent" in the environment and that cotton had been "wrongly cited as a water-intensive crop".

The US trade body also said that the "undeniable difficulties" of cotton farmers in west Africa were the result of many factors including "corporate monopolies and the rejection of genetically modified cotton by farmers".

CCI provided a range of research and information to back up its sustainability claim, maintaining that the cotton was a natural, renewable, biodegradable and sustainable fibre.

The ASA noted CCI's research but also said that there was "reputable scientific opinion" that was concerned about the longer term impact.

Advertising regulators added that there was a "division of informed and scientific opinion" as to whether cotton was a water intensive crop.

The ASA said that in relation to the complaint that US subsidies hurt cotton farmers in the developing world, it noted that the World Trade Organisation had opposed these payments in 2005.

There was not, the regulator said, "universal acceptance" that the US cotton industry had no negative impact on economies on developing countries.

The ASA concluded that because there was no universally agreed definition of sustainability and there appeared to be "a significant division of informed opinion as to whether cotton production in the US could be described as sustainable" the ad should not continue to run.

It said that in this context the term "sustainable" was likely to be ambiguous and unclear to consumers and that the CCI had not justified the claim.

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