McDonald's, Burger King and KFC are the latest popular high street chains found to be serving drinks containing faecal bacteria.
Three weeks after the BBC's Watchdog programme revealed faecal coliforms were widespread in ice served at some of the UK's favourite coffee chains, it has exposed the same hygiene issue at popular fast food outlets.
"The team tested ice from 10 random branches of each restaurant across the UK and found coliforms in ice at 3/10 branches of McDonald’s, 6/10 branches of Burger King and 7/10 branches of KFC," says Huffington Post.
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"Four of the samples taken at Burger King and five at KFC were described as having 'significant' levels of coliforms."
Government guidelines state the level of such bacteria in water for human consumption should be zero.
Tony Lewis, head of policy and education at the Chartered Institute of Environmental Health, who is working with Watchdog, told iNews the findings were "concerning".
He said: "When we're finding the sorts of numbers we're finding here, you have to look at the people making the ice, handling the ice, which they then transfer into customers' drinks.
"And then you also have to look at hygiene failure with potentially the machines themselves: are they being kept clean?"
McDonald's published a statement from Tom Humphrey, an independent professor of bacteriology and food safety, stating that E. coli - "the bacterium that is the most accurate and reliable indicator of faecal contamination" - was not found in any of its samples.
It acknowledged that "low levels of two other indicator bacteria, coliforms and enterococci, were found", but said these were not "reliable indicators of potential health risks".
The company added that it regularly reviews hygiene procedures, saying there were no "specific ice production standards in place" but it would be willing to work to industry bodies to develop an "agreed standard".
KFC said it was "shocked and extremely disappointed" at the findings and had shut down ice machines at affected stores to conduct inspections and cleaned and inspected machines at every other UK store.
Burger King said it is working with franchisees to "reinforce" its strict cleanliness and hygiene procedures.
Faecal bacteria found at Starbucks, Costa and Cafe Nero
Disease-causing bacteria found in faeces have been discovered in iced drinks being serviced at Costa, Starbucks and Cafe Nero.
A BBC Watchdog investigation into of ice samples and the cleanliness of tables, trays and high chairs at the three coffee chains found "seven out of 10 samples of Costa ice were found to be contaminated with bacteria found in faeces".
In addition, "at both Starbucks and Caffe Nero, three out of 10 samples tested contained the bacteria known as faecal coliforms".
These kinds of bacteria are "opportunistic pathogens - the source of human disease", said Tony Lewis of the Chartered Institute of Environmental Health.
"The level of contamination of faecal bacteria concerns me a great deal… These should not be present at any level - never mind the significant numbers found."
All three chains said they had already taken action.
A spokesperson for Costa said: "We were disappointed with the findings, especially as these stores are all rated 'very good' with a the top hygiene rating of five," reports the Daily Telegraph.
"Following these results we took immediate action to review our food safety procedures and have updated our ice-handling guidelines and are in the process of introducing new ice equipment storage across our estate."
Starbucks said they had "moved quickly" to launch their own investigation.
"All employees nationwide have received updated training on our high standards of hygiene including ice handling," added a spokesperson
Cafe Nero said it was carrying out "a thorough investigation" and that "99 per cent of our stores are rated as very good, good or satisfactory by their local [Environmental Health Officer) - making us one of the most highly rated businesses on the high street".
Watchdog is on BBC1 at 8pm tonight.
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