Despite the nationwide phase-out of leaded petrol from service stations over 30 years ago, leaded fuel remains a health concern in New Zealand due to its ongoing use in aviation and motor sports. A recent study by University of Otago public health researcher Professor Nick Wilson and independent researcher Dr John Horrocks highlights the continued presence of leaded petrol in many piston-engined light aircraft, some helicopters, and motor racing vehicles, exposing people to the toxic metal.
The researchers estimate that approximately 9 million litres of aviation gasoline (Avgas) imported into New Zealand during 2024 contained nearly five tonnes of elemental lead. Avgas in New Zealand contains lead concentrations significantly higher than those found in petrol before unleaded fuel became standard in 1996.
In a briefing from the Public Health Communication Centre, the authors urge New Zealand authorities to develop a formal strategy to phase out leaded fuels in aviation and motor racing, advocating a transition to unleaded alternatives. This approach mirrors regulatory developments in the United States, where the Environmental Protection Agency (EPA) has identified aviation gasoline as the primary source of lead emissions in the atmosphere and is advancing a plan to eliminate leaded aviation fuels.
Lead is widely recognized as a potent neurotoxin with no safe level of exposure. Children are especially susceptible to neurological damage, which can manifest as developmental delays, learning difficulties, irritability, and a range of other physical and cognitive symptoms. Adults exposed to lead face increased risks of cardiovascular problems, kidney damage, reproductive issues including miscarriages and premature births, as well as neurological impairments such as memory loss and mood disorders. At high levels, lead poisoning can be fatal.
Dr Horrocks emphasized the urgency of addressing lead exposure, noting the New Zealand government’s recent directive requiring all new plumbing products that come into contact with drinking water to be lead-free. Professor Wilson pointed out that individuals who handle leaded fuel, work on aircraft engines, or reside near airports servicing piston-engined aircraft may be particularly vulnerable to lead exposure. Supporting this, research from the United States has shown elevated blood lead levels in children living close to airports used by similar aircraft.
The researchers recommend that New Zealand adopt a precautionary approach similar to that of the United States, including the implementation of a phased plan to eliminate leaded aviation fuels, stronger health and safety protocols for those handling these fuels, and robust oversight to manage the transition to unleaded alternatives.