Lead-based paint in construction work

Workers in different trades and tasks can be exposed to residual lead based paint at construction sites. Instances include restoration of heritage buildings and demolition work where structures with a high percentage of lead based paint are present. Surface preparation for repainting or work such as welding on structures with lead paint can also expose construction workers to lead hazards.

Most buildings and homes decorated in Australia before 1970 contain lead paint. Old paint on metal bridges and plant may also contain lead. Deteriorating paint can peel off in large pieces, flake off in smaller chips or into a fine powder. Lead paint can be dangerous if it is peeling or breaking down. Old lead paint is not only confined inside the building, but may also contaminate other nearby areas, such as soil underneath the house or building. In addition to exposure in the workplace, workers can also carry small amounts of contaminants in their clothing and thus expose their families, particularly children, to lead.

Lead paint and lead contaminated dust is a major source of health risks to children and adults and control measures for the removal of lead dust or old paint are very important.

The hazards

Lead can harm virtually every organ in the human body, especially the brain, kidney and reproductive system.

Lead can enter the body through several routes, for example the respiratory tract, the gastrointestinal tract and through skin absorption. Lead gets into the body when you breathe in lead dust or fumes in air. If you swallow food or water that is contaminated by lead dust, small amounts of lead can gradually build up in the body and cause health problems.

Most people with increased blood lead levels are asymptomatic; adults may not display symptoms until blood levels reach 60 micrograms per decilitre (µg/dL) or 2.9 micromoles per litre (µmol/L) and above. Children generally do not show symptoms of lead intoxication until blood lead levels reach 45 to 55 µg/dL (2.7 to 2.64 µmol/L). Yet, some may be asymptomatic even when blood lead levels are as high as 60 to 70 µg/dL (2.89 to 3.38 µmol/L).

The National Health and Medical Research Council has set guidelines for permissable levels of lead in the blood and in ambient air in Australia. It set a specific goal "to achieve for all Australians a blood lead level of below ten micrograms per decilitre (0.48 micromoles per litre)."

Lead cannot be excreted. It stores in the body for up to 20-30 years in bone, from where it can be mobilized back into the blood. From a single exposure, lead is readily absorbed and quickly distributed to the following areas of the body: blood (1%), soft tissue (4%) and bones/teeth (95%). Anaemia can occur if lead accumulates in blood and in blood-forming tissues (bone marrow). Lead distorts the production of red blood cells in the body.

When symptoms first appear, people usually feel a headache or lethargy. Symptoms of moderate to severe exposure include irritability, abdominal pain or constipation, aggressiveness and colic leading to seizures and death. Lead poisoning in children may manifest as developmental delay, learning difficulties or other behavioral problems.

Protection

When a lead based problem is identified and/or known at a construction site, suitable measures must be taken from the beginning to prevent exposure. This is a mandatory process that must be complied with under the NSW OHS Act (2000). Following are guidelines to protect you during work by reducing the possibility of being exposed to lead dust or fumes.