Starbucks and Caffè Nero have launched investigations
Several coffee chains say investigations have been launched after a probe found ice from three firms contained bacteria from faeces.
A BBC Watchdog investigation, which aired on Wednesday night, said samples of iced drinks from Costa Coffee, Starbucks and Caffè Nero in the UK contained "varying levels" of the bacteria.
Cleanliness of tables, trays, and high chairs at the chains was also tested at 30 British branches.
Seven out of 10 samples of Costa ice were found to be contaminated.
Three out of 10 samples tested at both Starbucks and Caffe Nero contained the bacteria known as faecal coliforms.
Caffè Nero said in a statement to Newstalk: "At Caffè Nero we take the cleanliness and safety of our stores very seriously. We have a team dedicated solely to ensuring that all aspects of safety are maintained and our stores have detailed and timely cleaning schedules to ensure that they are kept up to standard.
"These standards are regularly audited by our operations team.
"Our food safety standards and procedures are signed off by our Primary Authority Partner, Eastleigh Borough Council who also work with us to continuously improve our high standards.
"All of our staff are trained on these procedures and 99% of our stores are rated as very good, good or satisfactory by their local EHO - making us one of the most highly rated businesses on the high street.
"We are concerned to read the findings in BBC Watchdog's recent report and a thorough investigation is now underway and the appropriate action will be taken."
A Starbucks spokesperson told Newstalk: "We want to reassure our customers that we take hygiene and cleanliness extremely seriously.
"We have moved quickly to conduct our own investigation into the claims.
"All employees nationwide have received updated training on our high standards of hygiene including ice handling.
"Nothing is more important to us than the safety of our customers."
Costa told the BBC it had updated its ice-handling guidelines and was in the process of introducing new ice equipment storage.
Dr Lisa O'Connor is chief specialist in biological safety at the Food Safety Authority of Ireland (FSAI).
She told Newstalk Breakfast not all of the bacteria found is necessarily directly from faeces, it is a general indicator test.
"It's an indicator - it doesn't mean that faeces is in the food", she said.
"We've done surveys similar with the environmental health officers in the HSE, they're the people who inspect these type of premises.
"They would routinely take samples in a premises if they were concerned.
"But every year, we also do these targeted surveys where we get large numbers of samples."
Dr O'Connor says their last ice test here found 2% of samples taken had E. Coli present.
"When we give advice about how to handle ice hygienically, one of the first things is to advise on storing the ice bucket in the machine itself.
"So for example when the ice is being transferred from the ice machine into the bucket that the hands that come in contact with that have been cleaned before".
She also says where there is a lot of meltwater present, more likely to find these organisms.