Confidential details about customers are being put at risk because of the marketing policies in which some firms are engaging, a new survey has claimed.

The survey of 900 firms, carried out by data protection company StrongMail, revealed that 61 per cent of marketing executives admitted to losing personal details about customers over the past two years.

In 9 out of 10 cases where data has been lost or stolen, the customer involved was not told of the breach.

One reason for the lack of security around personal customer data is the growing habit among firms of outsourcing marketing and IT activities to third parties in an effort to win new business.

According to the survey, one in 14 firms admitted passing on details about customers’ sexual orientation; one in 10 shared information about customers’ religious beliefs; one in seven gave out details about ethnic background; and one in five conceded that they had handed on credit card details.

Paul Bates, managing director of StrongMail UK, said: “Businesses have a moral, ethical obligation to keep private, personal customer data safe and secure.

“They should not be handing it out to third parties in the hope of making a fast buck. If they choose to do this, and then lose customer data, then they should at least be obliged to admit it.”

Despite lapses, the majority of firms reported that they observed the rules on data privacy and security, with 87 per cent of data protection professionals and 69 per cent of marketers insisting that their organisations complied with the law.