UP to 12,000 households and businesses in parts of Scotland have been warned not to drink or cook with tap water after "higher than expected" levels of aluminium were found.
Scottish Water broadcast vans toured affected areas in parts of Glasgow and Stirling yesterday, warning residents of the danger - while there were reports of panic buying of bottled water at some supermarkets.
One major retailer said it had diverted a lorryload of bottled water to the area to meet the sudden demand. There were long queues at outlets such as Morrisons at Anniesland in Glasgow. Other supermarkets, including some in Milngavie, East Dunbartonshire, reported that their stocks were beginning to run low.
Scottish Water said earlier yesterday it was giving priority for bottled water to hospitals, care homes and vulnerable customers. Last night, it announced it had set up seven distribution points for bottled water and would also be handing out water to some households in the affected areas, which include Milngavie, Bearsden, Strathblane and Blanefield, Mugdock, Faifley, Hardgate and Cochno.
Mr Geoff Aitkenhead, Scottish Water's asset management director, said: "We would like to reassure our customers in the area that this is a precautionary, temporary measure and we are doing everything possible to restore normal supplies as soon as possible. We would like to apologise to people in the affected areas."
The advice, issued in conjunction with the consultant in public health medicine at NHS Greater Glasgow and Clyde, is that the contaminated water should not be used for drinking, food preparation, making babies' feeds or brushing teeth. The water can still be used for washing clothes, baths and showers and for flushing toilets.
The high aluminium levels were detected in water analysed at the Burncrooks water treatment works, north of Milngavie. The works, which supply about 50,000 people in East and West Dunbartonshire and Stirling, were upgraded in 2009 in a 2.6 million project to improve the "security of supply".
Bearsden resident Margaret Watt, chairwoman of the Scotland Patients' Association, said: "Aluminium is very dangerous to the body and Scottish Water should be getting their finger out to make sure this gets dealt with as quickly as possible."
Dr Eleanor Anderson, consultant in public health medicine at NHS Greater Glasgow and Clyde, said: "It is unlikely that anyone who has drunk or cooked with the water will experience any immediate or long-term health effects.
"If, however, anyone from the affected areas develops gastro-intestinal symptoms within the next 24 hours, such as diarrhoea and vomiting and are concerned, they should contact their GP or NHS24."
A spokeswoman for the Scottish Environment Protection Agency (SEPA), said: "Water and discharge samples have been taken for analysis and a SEPA officer will inspect the burn again this evening and over the weekend.