Rainwater in Port Pirie
Drinking rainwater is a source of lead exposure which, together with other exposure sources around Port Pirie, can cause elevated blood lead levels. Testing of rainwater in Port Pirie has found lead levels up to 10 times the Australian Drinking Water Guideline.
Rainwater samples in Port Pirie often exceed the Australian Drinking Water Guideline maximum level of lead in drinking water of 0.01 milligrams per litre (mg/L). Lead can be harmful to people of all ages but the risk of health effects is highest for unborn babies, infants and young children.
It is recommended that you do not drink rainwater in Port Pirie.
The following recommendations explain how you can avoid health risks from rainwater in Port Pirie:
- Drinking, cooking and food preparation
- Bathing and showering in rainwater
- Using rainwater in the garden
- Water filters
- Maintaining a rainwater tank
- Rainwater testing
Why you need to be careful using rainwater in Port Pirie
Rainwater in Port Pirie contains lead. Studies have shown that contamination can be at levels high enough to cause serious health concerns or poisoning if drinking rainwater or using it in any circumstance where the end product is consumed. This risk can be easily avoided by drinking and using mains or bottled water.
Drinking contaminated rainwater is one of the ways lead can enter your body. Together with other exposure sources around Port Pirie, consuming rainwater can cause elevated blood lead levels, often above the National Health and Medical Research Council (NHMRC) recommended exposure investigation level of five micrograms per decilitre (μg/dL).
Pregnant women and young children should not use or drink rainwater collected in Port Pirie.
For more information on how lead enters your body and the effects lead exposure can have on you or your unborn child, see the Lead page.
It is recommended that you do not drink rainwater in Port Pirie, particularly if mains water is available. This includes use for teeth brushing, as rinse water is often swallowed, particularly by children.
Rainwater should not be used for any purpose where the end product is consumed (by either eating or drinking). This includes using rainwater for:
- preparing baby formula
- baby foods
- the sterilization of baby equipment
- tea and coffee
- making ice cubes.
Human skin does not absorb much lead, so it is acceptable to use rainwater for bathing and showering. However, young children may drink bath or shower water so it is recommended that rainwater is not used for these purposes.
Rainwater can be used for watering non-edible gardens and irrigating lawns, but it should not be used to water edible fruit or vegetables. Mains water should be used for watering home-grown produce.
Poultry and other animals should not be given rainwater for drinking or be provided grass cuttings to forage on from lawn that has been watered with rainwater.
Dusty outdoor hard surfaces such as paved pathways, patio areas, cement driveways and veranda's can be hosed down with rainwater.
Brass or chrome plated brass plumbing fittings in Australia contain lead and have been a source of drinking water contamination. Water sitting in taps and pipes, particularly overnight, can leach lead from fittings into drinking water. This predominantly impacts the water that comes out when the tap is first turned on.
If these fittings are used with rainwater, the possibility of lead leaching into water may be slightly higher compared to mains water due to the softness of rainwater (which makes it more corrosive). Lead leached from fittings can generally be avoided by flushing the first few litres of water that has been sitting in the taps and pipes overnight or for extended periods of time.
To ensure products that come into contact with drinking water do not leach lead into water, it is recommended that they meet the ‘Australian Standard 4020 (AS/NZS 4020)’. Plumbing suppliers and professionals should be able to provide advice on this matter.
Although taps containing lead can be a source of water contamination, lead-contaminated dust, along with lead paint and lead flashings, account for most of the rainwater contamination in Port Pirie.
Rainwater is suitable for plumbing into toilets.
There are many filters and filtration systems available, including those purchased from supermarkets claiming to remove lead from drinking water. Many of these claims are based on removing lead from water that already has low lead levels near or below the Australian Drinking Water Guideline (0.01 mg/L).
These filters are not designed, tested or certified to remove the high levels and ‘type’ of lead that is found in rainwater in Port Pirie.
If there is no alternative to using rainwater in your home, there are a small number of specialised filters that may be suitable for reducing lead from highly contaminated rainwater. Even with these filters, complete removal of lead from rainwater may not always occur.
Boiling water does not eliminate lead from rainwater; in fact, because some of the water evaporates during the boiling process it can actually increase the lead content in the water.
You should assume that all rainwater in Port Pirie contains lead. Lead levels will vary considerably depending on the age of the house and tank, type of tank, rainfall, maintenance of tank, collection surface and the location of the house in relation to the smelter and the railway line.
It is recommended that tanks are fitted with a first flush diverter and SA Health’s rainwater tank and maintenance guidelines are followed. Guidelines include:
- not collecting water from sections of roof that have lead flashings
- not collecting water from roofs painted with pre-1980s’ paint
- minimising the amount of leaves and organic matter that can enter the tank.
Tanks should be examined for accumulation of sludge at least every two years. Water that is in contact with contaminated sludge can have considerably higher lead levels than water in the rest of the tank. De-sludging and cleaning may help to remove some of the lead from your tank, but will not guarantee a lead-free water supply and the tank will get re-contaminated. It is also important that the material removed from your tank during de-sludging and cleaning is not used on the garden as it will contaminate the soil.
Rainwater can be tested for lead contamination, but sampling is unreliable for measuring ongoing lead levels because levels can change quickly after rain events and during long dry periods. Therefore, testing cannot be used to determine if rainwater is safe to drink due to the variability and seasonal fluctuation in smelter emissions, rainfall and lead dust movements.
For more information on general rainwater testing, see the Rainwater page.
For further information on lead safe practices, contact the Environmental Health Centre or SA Health's Scientific Services. Additional information on reducing your exposure to lead is also available on the following pages: