AS Muslims observe Ramadan, the Food Standards Agency and Lancashire Trading Standards are warning people about fake bottled water described or labelled as Zam Zam water.
Tests have shown that Zam Zam water sold in the UK, or brought into the UK for personal consumption, contains high levels of arsenic or nitrates.
Zam Zam water is sacred to Muslims and comes from a specific source in Saudi Arabia. It cannot be exported under Saudi law. As a result, any water on sale in the UK that is labelled as Zam Zam is of uncertain origin.
Tests carried out on water described as Zam Zam in the UK over the past few years, including water brought into the country for personal consumption, have indicated the presence of arsenic at almost three times the legal limit. Drinking water that is contaminated with arsenic could contribute to an increased risk of cancer.
County Councillor Albert Atkinson, deputy leader of Lancashire County Council, said: "If people see Zam Zam water on sale in Lancashire then please report it to our Trading Standards team. We'd also recommend that people avoid drinking any water described as Zam Zam that is on sale in the UK.
"There is no completely safe level of arsenic in water and the more arsenic consumed the greater the risk. However, if anyone has occasionally drunk small amounts of this fake Zam Zam water, the risk to health for adults and older children would be very low."
Due to the level of nitrate that could be present, infants may also be sensitive. Trading Standards do not recommend that they are given this water to drink.
The FSA has consulted on this issue with its Muslim Organisations Working Group, which advises the agency on appropriate foods for Muslim faith groups.
If consumers find any water on sale in the UK that is labelled as Zam Zam, they should contact Consumer Direct on 08454 040506 for Trading Standards to investigate further.