Lead: Frequently Asked Questions

Lead is a metal which, because it is cheap and useful, is found in many products and in many places in the environment.

Lead entering our bodies may cause serious long-term health problems, especially for young children and pregnant women. Lead can affect children by causing learning and attention problems, hearing loss, slowed growth and behaviour problems.

Lead can affect adults too. Low levels of exposure can cause joint and muscle pain, high blood pressure and infertility. Higher levels can cause memory loss, nerve problems and, at very high levels, fits or even death.
Lead gets into our bodies when we breathe in lead dust or fumes in the air or if we eat food or drink water that contains lead.

Why are children at risk?

Lead can be damaging to both the unborn child and children less than five years. This is because:

• Their developing brain and nervous systems are more fragile.
• Children absorb much more lead than adults do if it is eaten - up to 50% in children compared to 10% in adults.
• Normal activity in children (eg putting fingers in mouth, crawling, and chewing on objects) makes them more likely to find and swallow lead.
• Children who eat non-food substances (eg dirt) are at even greater risk.

Why is there lead in soil?

All soils contain lead in varying amounts, depending on their geological source. Factors which affect the amount of lead in soil include:

• Age and building material used in house. Most houses built before 1970 contain lead-based paint. After 1970 lead levels in paint dropped, but old paint may be unsafe if disturbed during renovations. Slag, containing lead, has also been used in parks and gardens and homes as infill and to provide drainage.
• Proximity to emissions. Homes near industries that produce or use lead may have lead dust fall into their homes or gardens.
• Homes near heavy traffic may have higher levels of lead in soil due to exhaust from lead petrol, although this has decreased with the use of unleaded petrol.
• People may bring lead into their homes and yards as a result of their work or hobbies (eg lead solder, furniture restoration, lead sinkers).

A level of 300 parts per million (ppm) of lead in soil has been set as a level for further investigation by the National Health and Medical Research Council (NHMRC) and the Australian and New Zealand Environment Conservation Council (ANZECC).

How do you know soil lead levels?

The only way to know soil lead levels is to arrange a soil test with a consultant. Usually four separate areas in the yard will be tested. A written report will be given to the home owner on the levels within each area and the average level across the block. The report will then say if the soil lead levels are above or below the soil lead level set by the NHMRC and ANZECC.

What can be done?

The NSW Interdepartmental Lead Taskforce, Environmental Protection Authority, 1994 document NSW Lead Management Action Plan sets the following levels for remediation which could be used as guidelines for a site specific / child specific residential property.

• < 300 ppm - no action
• 300 - 1,500 ppm - grass cover or other appropriate barrier
• 1,500 - 5,000 ppm - top dress with 50 mm clean soil and grass cover
• > 5,000 ppm - soil replacement (top 200mm)

Management strategies should recognise that there is a difference between contaminated land that is a direct and immediate health risk and that which does not pose a health risk (but should still be recognised as a potential hazard).

What can the homeowner do?

Homeowners who think they may have lead in their soil should get advice from the NSW Department of Environment and Climate Change (formerly EPA), local government or Hunter New England Population Health on reducing soil lead levels.

It is recommended that all homeowners have good grass cover in their yards. Exposed soil in gardens should be covered with a groundcover such as mulch, pinebark or gravel that will provide a barrier and reduce possible exposure to available lead in the soil.

Where else may lead come from in the home?

Paint

Nearly all cases of acute lead poisoning in children admitted to children's hospitals in recent years have been attributed to home renovation activities.

Most houses built before 1970 contain lead paint. After 1970, lead levels in paint dropped but old paint and flaking paint may be unsafe if disturbed during renovations. Unsafe renovations where old lead paint is removed or prepared for over-painting are the most common causes of lead poisoning.

Open-flame torches create dangerous fumes. Dry sanding without water creates lead dust. Fumes and dust can be breathed in, eaten or can contaminate the house, its contents and surrounding areas. You can renovate safely if you take simple precautions and use the right equipment.

Lead contaminated dust

Many older Australian homes and buildings have lead dust in their ceiling cavities, wall cavities and under the floor. This may have come from industrial pollution, exhaust emission from use of leaded petrol, unsafe renovations or demolitions. To reduce this hazard, it is recommended that cracks, ceiling roses and some vents be sealed to stop dust leaking into rooms