SINGAPORE - It might be safer to give the right amount of money to food sellers, and not get back any change from them.
A local study has found two types of bacteria on currency notes and coins obtained from a local canteen.
The bacteria found are of the S. aureus and B. cereus species, which are among the most common bacteria types that lead to food poisoning.
The canteen cannot be named due to an agreement it has with the researchers.
Ten two-dollar notes, five one-dollar coins and five 10-cent coins were acquired from the canteen on a day in July for the Lifebuoy Germ Protection Study. Conducted by an independent microbiology laboratory, it found both the notes and coins had bacteria, though the amount was not measured.
The study aimed to identify the bacteria on money and determine the efficacy of Lifebuoy anti-bacterial soap, soap without anti-bacterial properties, and water on the bacteria identified.
S. aureus is usually found on a person's skin, hair, nose and throat. B. cereus is present in food left at room temperature for too long.
These were the second and third most common contaminants found in food and the environment from 2009 to last year, according to the Health Ministry's latest Epidemiological News Bulletin published last month.
However, these may not necessarily be the main causes of food poisoning because it may be difficult to identify viruses that can be triggers too, said Associate Professor Paul Ananth Tambyah, president of the Society of Infectious Diseases (Singapore).
The most common contaminant is E. coli, a bacterium found in human intestines. This was not found on the notes and coins in the study.
"What that tells me is the hawkers at that particular canteen wash their hands after they go to the toilet, so at least that's a bit reassuring," he said.
The bulletin also reported that most of the food establishments involved in food poisoning outbreaks from 2009 to last year were restaurants.
Hawker centres and foodcourts made up less than 15 per cent.
Proven food poisoning cases have increased significantly in the past few years, from about 100 in 2006 to about 250 last year.
These cases do not include those where complainants were uncontactable or did not seek medical treatment.
The findings of the Lifebuoy study were released yesterday to mark Global Handwashing Day next Monday.
The Health Promotion Board launched the Hand Hygiene Programme last month. It will be rolled out at all primary schools over the next three years.
"It is something our mothers taught us - always wash your hands before eating or preparing food. It is good this investigation reminds us of the importance of hand sanitation at eating places to protect ourselves from food poisoning and other illnesses," said Prof Tambyah.