Public health priority: Routine.
Public Health Unit (PHU) response time: Respond to confirmed cases within 3 working days. Enter confirmed cases on NCIMS within five working days
Case management: Ascertain source where possible, and recommend risk reduction measures. Notify SafeWork NSW, where appropriate, of cases from occupational exposure.
Contact management: Consider identification of other persons affected by the same source or the transfer of contaminant to other household members.
A confirmed case requires a person with a venous blood lead level of ≥5 µg/dL (0.24µmol/L).
Elevated blood lead level is to be notified by laboratories on diagnosis (electronically or by routine mail to the Public Health Unit).
Only confirmed cases should be entered onto NCIMS.
Lead is a naturally occurring metal found in the Earth’s crust. It has a wide variety of uses in manufacturing due to its properties of being soft, malleable and corrosion resistant. Australia is one of the world’s major lead-producing countries.
Most people in Australia live in places where there are very small amounts of lead in food, drinking water, air, dust, soil and consumer products. Exposure to higher than background levels of lead may occur in areas where there are industrial sources of lead or through exposure to lead-containing paint. However, people’s exposure to lead has substantially reduced in recent decades due to national initiatives which have restricted the addition of lead to paint and petrol, and the use of lead in consumer goods (e.g., toys, cosmetics and cans). In addition, lead management programs in endemic areas, such as Broken Hill, have resulted in a steady decline in blood lead levels in children.
Lead and lead compounds are not beneficial or necessary for human health and can be harmful to the human body.
Elevated blood lead levels usually derive from the ingestion of lead-containing substances, the inhalation of lead-containing dust and transfer from mother to foetus. Less commonly, some forms of the metal can be absorbed through the skin. Young children (under 5 years) and pregnant women are especially vulnerable to environmental exposure to lead, but adults engaged in particular occupations and hobbies are also at risk.
The average blood lead level among Australians is now estimated to be below 5 micrograms per decilitre (5 µg/dL or 0.24 µmol/L). A blood lead level greater than 5 µg/dL (0.24 µmol/L) suggests that a person has been, or continues to be, exposed to lead at a level that is above what is considered the average ‘background’ exposure in Australia.
Note that in communities that are at risk of known excess lead exposure due to industry (such as Broken Hill), Public Health Authorities run specific programs to monitor and reduce lead exposure.
Health effects as a result of lead exposure differ substantially between individuals. Factors such as a person's age, the amount of lead, whether the exposure is over a short-term or a longer period, and the presence of other health conditions, will influence what symptoms or health effects are exhibited. Lead can be harmful to people of all ages, but the risk of health effects is highest for unborn babies, infants and children under 5 years.
It is well established that blood lead levels equal to or greater than 10 µg/dL (0.48 µmol/L) may have harmful effects on many organs and bodily functions. Effects such as increased blood pressure, abnormally low haemoglobin, abnormal kidney function, long-term kidney damage, behavioural problems, cognitive impairment and abnormal brain function have been observed at blood lead levels between 10µg/dL and 60 µg/dl (0.48-2.89 µmol/L) in adults and children.
Encephalopathy—which is characterised by irritability, agitation, poor attention span, headache, confusion, uncoordinated walking or movement, drowsiness, convulsions, seizures or coma—can occur at blood lead levels of 100–120 µg/dL (4.82-5.79 µmol/L) in adults and 70–100 µg/dL (3.37-4.82 µmol/L) in children. In extreme situations, irreversible brain damage or even death can occur at these blood lead levels.
A comprehensive review of the health effects of lead by the National Health and Medical Research Council (NHMRC) in 2015 found an association between blood lead levels below 10 µg/dl (>0.48 µmol/L) and health effects in some population groups. However, there was insufficient evidence to conclude that lead at this level caused any of the health effects observed.
Within 3 working days of notification of a confirmed case, begin follow-up investigation.
Within 5 working days of notification, enter confirmed cases on NCIMS.
The response to a notification should be carried out in collaboration with the case's health carers and/or SafeWork NSW. Regardless of who does the follow-up, PHU staff should ensure that action has been taken to:
[For endemic areas, refer to existing local protocols and programs for managing lead notifications in children].
The protocol outline below is for new notifications. If the notification relates to follow-up from a previously notified blood lead level within the last 12 months (BLL), the PHU response can be modified according to the circumstances of the case.
Under 5 years
If non-occupational exposure, provide lead fact sheet on risk identification and management to the requesting doctor or case as appropriate.
Work-related exposures: Suggest case or treating doctor advise the patient to discuss BLL with their employer in the case of occupational exposure. Inform SafeWork in case of a cluster of cases.
Risk management: Offer counselling/home risk assessment to the case as appropriate.
Blood tests: Household contacts may need to be tested, particularly young children and pregnant women.
The main treatment for adults and children involves:
The case or relevant caregiver should be informed about the effect of the blood lead level and the likely causes. In particular, emphasis should be placed on minimising the exposure of young children and pregnant women to sources of lead.
Information for community members and health care professionals is available at Lead exposure in children and adults, the Office of Environment and Heritage Pollution, or by telephone on 131 555.
Other information on lead is also available from the NSW Environment Protection Authority
The case or relevant caregiver should be asked about sources of lead contamination, such as:
Further information on occupational sources of lead can be obtained from SafeWork NSW on 13 10 50.
None
If the source of the exposure is not clear after the initial investigation has taken place, the PHU should arrange for an environmental assessment of the residential area if the case's blood lead level is in excess of 25 µg/dL (1.2 µmol/L) and/or the implicated source may affect the broader community.
The Public Health Unit response to any exposures identified will need to be tailored to the specific risks identified. General advice can be provided by telephone or the provision of information such as factsheets, or advice on managing lead paint in the home (for example, refer to Lead Safe Blitz video).
In some instances, an EHO may provide an assessment through a home visit. Householders (or the landlord of the property) may also be advised to engage the services of an independent assessor or remediator to advise or assist with exposure risk reduction.
Contacts can be defined as all persons exposed to the same source as the case (see case definition), or who have secondary exposures (e.g., children of persons who bring lead dust home on their clothes).
Blood lead testing should be recommended for:
Advise susceptible contacts (or parents/guardians) of the risk of elevated blood lead levels. In particular, emphasis should be placed on minimising the exposure of young children and pregnant women to sources of lead.
Multiple notifications relating to individual workplaces should be referred to SafeWork NSW for further follow-up and management. Further advice can be sought from the Environmental Health Branch, Health Protection NSW.
In circumstances where there appears to be geographical clustering of non-occupational cases, excluding known lead endemic areas (especially in children aged under 5 years), and the source is unknown, further investigation may be warranted. Further advice can be sought from the Environmental Health Branch, Health Protection NSW.