Two thirds of UK citizens don’t know that if they sign up for a free email service their messages could be scanned for advertising opportunities.

Of the 1,580 UK adults surveyed by GMX, a free email provider, 56% said they were concerned by the practice and 19% professed to be anxious. One in four felt they should be allowed to opt out of having their emails scanned.

Strangely, recognition of scanning practices has fallen. In 2008, 40% of the UK adults surveyed knew nothing of the practice, compared to this year’s figure of 65%.

This negativity towards the practice was even more pronounced when it came to children’s email accounts. Almost half the respondents felt that parents should be informed if scanning was happening and similar numbers felt it should be banned for all children’s accounts.