Email adverts for cheap Viagra and get-rich-quick schemes are costing UK businesses £50,000 a year each, according to research by email security company MessageLabs.
Spam email clogs-up email servers and wastes expensive internet bandwidth, according to the study of 200 UK businesses. If found, a third have problems dealing with unwanted email.
This findings are backed by a survey by analysts Gartner.
MessageLabs said an average worker on £25,000 a year spends ten minutes per day ridding their inbox of superfluous messages at a cost of £2 per employee to the company.
For a company of 100 employees, this amounts to £47,000 of wasted time per year.
But Jos White, founder of MessageLabs, criticised companies for not taking the problem of spam seriously.
"At the moment, little is being done to seek a remedy. Even in the US, where spam is a huge problem, less than half the businesses have measures in place to filter out unsolicited email," he said.
He said that even fewer businesses in the UK bothered with filtering, despite two-thirds of the respondents believing that spam should be regulated.
But these findings contrast with research done by DoubleClick, a US internet advertising company. It found that more than 82 per cent of internet users bought online at least once after receiving an email advert.
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