These guidelines provide a resource document for public health units who are involved in the investigation and management of people who have been exposed to lead (from non-occupational sources).
Lead absorption from other than occupational sources is a condition which is notifiable to the Medical Officer of Health under the Health Act 1956. The levels of blood lead which are required to be notified in New Zealand are ‘lead absorption equal to or in excess of 0.24 micromoles per litre (µmol/l)’ or 5 micrograms per decilitre (µg/dl).
While the guidelines are applicable for any age, there is an emphasis on measures for managing cases of lead-exposed children. Originally published in 1998 and revised in 2007 and 2013, the 2021 revised guidelines were updated to take into account developments in the management of lead exposure in New Zealand and internationally.
The guidelines assist public health units to identify all contributory lead hazards and (open) exposure pathways using a combination of interview, visual observation, and laboratory testing. A management plan, typically incorporating both behavioural (educational) and environmental (abatement) strategies, can then be developed in consultation with the family. It must be emphasised that the guidelines aim to provide a ‘lead-safe’ environment; this is not the same as a lead-free environment.
The guidelines have been revised to incorporate the 2021 reduction in the notifiable lead absorption level in the Health Act 1956, which was reduced from 0.48 (or greater) micromoles per litre (µmol/l) to 0.24 (or greater) µmol/l. An updated graded response protocol has also been included which provides recommendations on appropriate responses to the results of the most recent blood tests from affected persons. These recommendations are based on international and national standards, but for all individual cases public health units should also be guided by the medical practitioner.
Properly applied, the guidelines help with determining:
- the risk of a lead hazard
- appropriate advice on managing the risk, including risk communication.
These guidelines exclude places of work, and ambient (outside) air.