The names and addresses of individual voters are being sold by councils to marketing companies for as little as half a penny, it emerged today.

Local councils are selling information from the electoral roll for £5 per 1,000 names under a little-scrutinised piece of legislation which allows the sale of such details for commercial purposes.

A report by the Information Commissioner and the Wellcome Trust today called for the provision - in operation since 2002 - to be abolished, saying it amounted to an unacceptable use of personal information and a breach of privacy.

The Representation of the People Regulations specify that councils may sell electoral roll details to companies for a variety of purposes. Typically, political parties and credit reference agencies have bought the information, but recently a booming industry has sprung up around direct marketing, much of it aided by the sale of names and addresses by councils.

Just over 3.5 billion pieces of "direct mail" -what most would think of as junk mail - are sent out in the UK each year, at a cost of £16 billion, according to the Direct Marketing Association (DMA).

Voters can tick a box on voter-registration forms - sent out in October each year - which removes them from the edited version of the electoral register that is put on sale. If they do not, their names and addresses are likely to be sold whenever a marketing company approaches the council.

The Data Sharing Review published today recommends the abolition of rules allowing the sale of such personal information. "We feel that selling the edited register sends a particularly poor message to the public that personal information collected for something as vital as participation in the democratic process can be sold to anyone for any purpose," the authors wrote.

One of the marketing companies mentioned in the report, B4U, received 1,600 complaints, including one from a police officer whose family's names and addresses along with a map to their house appeared on B4U's website.

B4U, which is based in Birmingham, was not available for comment.

The report also points out that although councils only sell names and addresses, "as more and more information enters the public domain in electronically accessible form" - for instance on social networking sites - the issues arising from services such as B4U's "go considerably wider".

One can imagine, for instance, a service that would cross-check electoral information with public profiles on sites like Facebook, so that they would know not only that a certain person lived at such an address, but that he was interested in golf, or travel to India, or a particular band, like Coldplay.

Neither the DMA nor the Local Government Association (LGA) could say how much money councils raise by selling such information but the LGA insisted it was not a revenue-raising activity. "Changing the law to prevent sales wouldn't make much difference to councils financially," an LGA spokesman said. "In fact not having to manage two separate registers - the edited and unedited one - would make things a lot easier."

The Direct Marketing Association disagreed with the Information Commissioner's proposals, saying that as long as voters are free to opt out of the register, the sale of such information should not be a problem.

A spokeswoman said that since 2002, 60 per cent of people had chosen to stay on the register that can be sold to companies, and that there was no evidence for the report's claim that "the language used (on registration forms) can be confusing."

That view is shared by 192.com, a company which sells electoral information to online retailers for anti-fraud purposes - allowing companies to check that an address entered by a customer is on the electoral roll.

"The Act gives people the right to opt out," Dominic Blackburn, product director at 192.com, said. "Consumers are asked every year if they want to. They can tick that box. There's no breach of privacy."

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