The acting Director of Public Health, Dr Mark Veitch, said today that water tests had revealed lead levels of between 16.1 micrograms a litre and 1370 micrograms a litre.

The safe drinking water guideline is 10 micrograms a litre.

The stainless steel rainwater tanks were made and sold by Kingston Sheetmetal between March 2010 and January this year.

Dr Veitch said that people should not use water from the affected rainwater tanks for drinking, brushing their teeth or preparing food.

"Water from the tanks is safe to use for cleaning and washing clothes and dishes, and for showering or bathing," Dr Veitch said.

"If you have been using a Kingston Sheetmetal stainless steel rainwater tank for household drinking water, you should stop using it immediately, and use an alternative drinking water supply.

"If you have been using one of these tanks for your drinking water you should discuss blood lead testing with your general practitioner."

The tanks were made using stainless steel panels joined by 50 per cent lead and 50 per cent tin solder, Dr Veitch said.

Australian Standards require jointing materials coming into contact with drinking water to contain no more than 0.1 per cent lead, and not to have a lead concentration in water over 10 micrograms a litre.

About 120 of these tanks have been sold since March 2010, mostly to people in southern Tasmania.

Dr Veitch said plants watered from the affected tanks were unlikely to have absorbed significant quantities of lead.

"People should not use water from these tanks as drinking water for pets or livestock."

Dr Veitch said prolonged exposure to high levels of lead in drinking water could increase blood lead levels and cause a range of health problems.

"The risk is greatest for young children and pregnant women."

Dr Veitch said that boiling the water does not remove the lead.