Reducing your lead exposure
Lead is a naturally occurring heavy, bluish-grey metal with a relatively low melting point (327°C). It is found naturally in the earth’s crust. The concentration of lead in soil is higher in mineralised areas. It is most commonly associated with other elements to form lead compounds. Galena is a typical compound, mined in Broken Hill and Mount Isa.
Main sources of lead are from mining, smelting, refining and historical contamination from old lead paint and petrol sources. Lead particles can be removed from the air by rain and by physical fallout into the surrounding environment. Once lead falls onto soil or water, it sticks strongly to soil and sediment particles, where it can remain for many years. The movement of lead into groundwater is highly unlikely unless rainfall is acidic.
People living near smelters, mines or transport routes can be exposed to lead by:
- breathing contaminated air
- swallowing dust, soil or drinking rainwater contaminated with lead
- living in older houses or using older painted furniture and toys.
People living in older houses or using older painted furniture and toys may be exposed to lead by:
- drinking water from old lead piping
- swallowing lead paint chips directly, or fragmented in dust and soil.
How lead enters the body
Lead can enter your body by breathing air containing very small particles, or by swallowing lead-bearing dust, soil or paint chips. Only very small amounts of lead on your skin can pass into your bloodstream, but if it is not washed off, it can be accidentally swallowed.
Once particles are swallowed or breathed in, the amount of lead that actually gets into your blood will depend on how old you are, when you last ate and how well the lead particles dissolve in the stomach or lungs.
Lead absorbed by a pregnant woman can also pass through the placenta to the baby. If exposure is ongoing, greater amounts of lead will accumulate in the body, especially in the bones.
How lead leaves the body
Shortly after lead is absorbed into your body, it travels in your blood to soft tissues and organs such as liver, kidneys, brain, muscles and heart. The lead can be either stored or excreted into your urine and faeces. The time it takes for most of the lead to be excreted depends on how long you have been exposed for.
If the lead is not excreted by the kidney or gut within a few weeks, the remaining lead moves to your bones and teeth. Some lead can be stored for up to 30 years in bone. This can move back into the blood during pregnancy, breast feeding, after breaking a bone, or due to osteoporosis.
Reducing your lead exposure
There are simple precautions you can take to reduce or prevent your exposure to lead. See the fact sheet on reducing your lead exposure (PDF 153KB) for tips on minimising your and your family’s lead exposure.
Further information
For further information on reducing your lead exposure, contact SA Health's Scientific Services on (08) 8226 7100.
How to reduce your exposure to lead
Visit the below pages for more information on how to reduce your exposure to lead: