Greening The Garden
An effective way to reduce lead exposure in your garden.
Gardening in Port Pirie
Lead has been present in the homes and gardens of Port Pirie for a number of decades.
It is only in more recent years that we have been aware of the harm that can be caused when this lead is absorbed into our bodies.
Young children are most at risk. They are also the group who play in our gardens and outside areas most frequently.
Landscaped gardens are a requirement for all new buildings in Port Pirie.
Landscaping may include removal of contaminated soil, covering (vegetating with drought tolerant plants, shrubs or trees, mulching or gravel) or sealing with pavers or concrete.
Bare soil, particularly in areas where children play should be covered to provide a barrier between potentially lead-contaminated dirt and children.
An effective way to reduce lead exposure in your garden, and to keep your garden free of dust and loose soil that can blow around and into your home, is to fully cover soil that may be contaminated.
It’s important to water the garden regularly, especially paths, roofs, walls and pergolas to suppress the dust.
A drip system can be a cost effective way to water your garden, but you will need an everyday hose to water the walls, paths etc.
Sweeping, dry dusting or using outdoor blower vacs should not occur in outside areas because they redistribute lead-contaminated dust and encourage entry of dust indoors.
Ways you can reduce your exposure to lead in the garden include:
The easiest and most effective method of reducing lead exposure is to remove the source. Unfortunately this is not always possible.
An alternative is to place a “barrier” between the source (in this case, tiny lead particles in the soil) and yourself. In the garden this can be achieved in a number of different ways.
A barrier over contaminated soils can consist of:
- plants, ground covers, or grass
- natural materials including mulch or pine or bark chips
- man-made substances can include gravel, crusher dust, pavers or concrete etc.
Bark chips and mulch will need to be replenished to keep an adequate barrier in place.
Mulch is an excellent barrier when used correctly.
It is important to cover the entire desired surface, and the mulched area should be “topped up” when the material starts to thin out over time.
Natural materials such as lawn clippings or fallen leaves are some of the best types of mulch and can often be obtained at little or no cost.
In general, the rules applied to the general garden can be applied to the vegetable garden and vice versa.
Pregnant women and young children should avoid eating home-grown/locally-grown produce, including eggs and honey, from Port Pirie.
Food grown or produced in Port Pirie may contain lead.
Below are some additional actions that can be followed when growing vegetables:
Research indicates that some leafy vegetables collect lead-bearing dusts more readily from the environment than other vegetables (lettuce, silverbeet, cabbage, broccoli and cauliflower example).
Because these vegetables are difficult to clean and remove all lead particles, they’re not recommended for consumption by young children or pregnant women.
Always remember to thoroughly wash all fruit and vegetables prior to storage and eating to remove any surface dirt which may contain lead.
It can be assumed that all soils in Port Pirie contain some level of lead contamination – therefore vegetable beds should be raised and good clean soil is recommended.
Compost and mulch are excellent natural ways of improving the nutrient content of your veggie beds. They can also be very cheap.
Compost provides organic matter – which helps to reduce the amount of accessible lead in the soil of vegetable beds. Increased soil quality will also promote vegetable growth.
Horse manure should be used with caution as it can often contain lead if collected from the Port Pirie area. This may then contaminate your “clean” soil.
After working in the garden, wash well and change into clean clothes, keeping your “gardening clothes” separate.
It is particularly important that the shoes you have worn are removed or cleaned prior to entering your home, as they can walk lead-bearing dirt onto your clean floor and into your carpets.
Children who play in the garden should always take their shoes off prior to coming indoors for the same reason.
This will also reduce your housework, as less dirt is brought into the home. Their hands will need to be well washed and dried after being in the garden.
Play equipment and toys that are left or kept outside should be hosed down or wet wiped regularly.
Sandpits should be covered when not in use.
Children need safe areas in which to play. Plans for your garden should include:
- barriers over bare soil, such as grass, ground covers or bark chips
- separate areas used by adults for hobbies or activities that may generate sources of lead exposure (for example, stripping down old furniture or spray painting cars)
- make sure that painted surfaces accessible to children are kept in good repair
- keep a cover over the sandpit, particularly if your garden is visited by furry friends.
The importance of washing your hands after being in the garden cannot be emphasised enough.
Dirt from under your nails and ingrained dirt should also be washed off – no quick rinses under a tap!
Children need to accept washing their hands as a normal way of life, particularly after playing or helping outside. Remember there are a number of germs in all soils.
Always wash your hands after being in the garden.
Although rainwater is a precious natural resource in our dry environment, it should be assumed to be contaminated by lead dust in Port Pirie.
Lead dust from roofs and gutters settle in tanks and will contaminate the water.
Rainwater can be used for watering non-edible gardens and irrigating lawns, however mains water should be used for watering home-grown produce.
Rain water should not be used to water edible fruit or vegetables.
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.
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.
You should assume that all rainwater in Port Pirie contains lead.
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.
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.
Tanks should be examined for accumulation of sludge at least every two years.
- In relation to domestic water conservation measures, plumb rainwater to toilets only and avoid plumbing rainwater to laundry taps.
- It is important to reduce the risk of consumption because rainwater collected in Port Pirie is highly likely to contain lead.
- Rainwater should not to be used for preparation of food or for drinking in Port Pirie — including making baby formula, cordials or sterilising baby bottles.
Boiling rainwater concentrates the lead within it.
Contact the Port Pirie Environmental Health Centre on (08) 8638 4100.
Address: 117 Gertrude Street Port Pirie South Australia