Lead exposure

Lead can be found in:

• batteries
• cigarettes
• solder
• fishing weights or sinkers
• firearms and ammunition
• printing materials (printer ink, typesetting materials)
• ceramic cookware, glazes and glass; particularly when improperly fired and then used in cooking or to store acidic, hot or alcoholic foods
• some imported cosmetics and pigments (colours)
• paints (particularly industrial paints)
• plastics and protective coatings
• imported toys (may contain lead or be coated with lead-based coating)
• playground equipment (paint coatings may contain lead, particularly if older than 1998)
• imported herbal preparations
• petrol (leaded petrol is no longer used in Australia except under special license) and petrol additives.

When absorbed into the body, lead will circulate in the blood and can remain in the soft tissues and organs (e.g. kidneys, liver and brain) and is stored in bone and teeth. Lead absorption through the skin is very slow although repeated exposure to low levels of lead can cause it to build up in the body.

Lead interferes with the production of haemoglobin (a protein in the blood which transports oxygen) which can cause tiredness and shortness of breath during physical activity. Very high levels of lead are uncommon in Australia but can be fatal.

The levels of lead detected in the Australian population have been steadily decreasing.

How does lead exposure occur?

Eating food and drinking water

There are very small amounts of lead in food and drinking water, however in Australia the lead levels in water are very rarely above the limits set by the Australian Drinking Water Guidelines (external site).

The maximum levels of lead allowable in food are set out in the Australia New Zealand Food Standards Code (external site) (the Code) by Food Standards Australia New Zealand (FSANZ). FSANZ monitors the food supply in Australia to ensure that food regulatory measures are adequate to protect consumer health and safety.

Canned food is no longer a source of dietary lead; all cans used in Australia now have welded seams (instead of lead soldered cans).

In Australia, dietary exposure of lead from food is below the determined low risk level and has decreased over the past decade.

Environment

The inhalation of lead can occur when tiny lead particles and fumes from heating, welding or lead contaminated dust are released into the environment.

Some hobbies and past-times can generate lead dust and fumes which may contaminate air, food, water and soil, including:

• restoration of boats, homes, cars or furniture covered with a lead-based paint
• pottery (glazing and firing)
• lead casting (production of ammunition, toy soldiers and fishing sinkers)
• burning of materials containing lead or covered with a lead-based coating (wood or plastics)
• soldering
• recycling materials containing lead or coated with lead-based products (motor vehicle bodies, batteries, electronic equipment)
• smoking (elevated blood lead levels are consistently found in adults and children whose parents smoke)
• lead lighting
• electroplating
• using firearms.

Pregnant women need to minimise their exposure to lead because it can cross from the mother to the baby through the placenta. Small amounts of lead can also transfer into breast milk. Pregnant or breastfeeding women need to keep well away from areas which may be contaminated with lead and avoid activities which generate fumes or dust that is contaminated with lead.

Young children are more sensitive to the effects of lead and are likely to absorb up to 5 times more ingested lead than adults. Children can often place objects in their mouths, suck their fingers and may swallow dust and soil, making them more vulnerable to lead exposure. Give young children regular meals and snacks – a child with an empty stomach can absorb 7 times more lead than a child that has eaten.

People with iron and calcium deficiencies also tend to absorb more lead and are encouraged to eat a balanced diet with adequate levels of calcium, iron, vitamin C, zinc and magnesium. Good sources of iron include poultry, red meat, liver, fish, fortified cereal, cooked beans/lentils, and green leafy vegetables. Milk, cheese and yoghurt are good sources of calcium.

Symptoms of lead exposure can be difficult to recognise. Your GP or doctor should be consulted if lead exposure is suspected.

Very high levels of lead in the blood (70-100 micrograms per decilitre (µg/dL) or greater) can cause acute lead poisoning and may occur during situations where lead is handled inappropriately or unsafely.

The absorption of very high levels of lead into the body is considered a clinical emergency and symptoms can include:

• convulsions
• stomach pain
• vomiting
• loss of consciousness and even death.

These instances are now extremely rare in Australia and there is more focus on long-term effects of ongoing exposure to low levels of lead.

Some of the long-term effects include:

• general fatigue
• headaches
• anaemia
• blood circulation problems
• weakness in the fingers, wrists and ankles
• reduced fertility
• reduced kidney and brain function.

Exposure guidelines for lead and lead compounds

In May 2015 the National Health and Medical Research Council (NHMRC) recommended that all:

• Australians should have a blood lead level that is not higher than 5µg/dL
• children's exposure to lead should be minimised
• women are advised to minimise their exposure to lead both before and during pregnancy and also while breastfeeding.

In 2015, the Department of Health WA (DoH) adopted the NHMRC recommendations.