Blood lead levels among children in the South Australian city of Port Pirie have risen to their highest since the current testing regimen began, alarming new government data shows.
The city, 230 kilometres north of Adelaide, is home to the Nyrstar lead smelter, and children are regularly tested to monitor their exposure to the toxic metal.
In 2020, the average blood lead level in tested two-year-olds reached 7.3 micrograms per decilitre (100ml) of blood.
The result was the highest level recorded since 2011 when a new testing program was introduced.
The state’s Department for Health and Wellbeing (DHW), which published the results on Monday, said the latest figures showed deterioration in all but one of the reported blood lead indicators.
But DHW director of scientific services David Simon said the results correlated with the plant’s activity.
“While these new results are very disappointing, they were not unexpected given the upward trend in average lead-in-air levels reported by the Environment Protection Authority through 2020 compared to 2019 when the smelter was shut down for extended periods of time,” he said.
“The increased lead-in-air contributed to the amount of lead-contaminated dust deposited in homes and public spaces across Port Pirie during the year, meaning more people were likely exposed.
“As a result, the improvements we saw in the first half of 2020 were not sustained and continued to plateau for the rest of the year.”
The World Health Organisation (WHO) says there is no safe level of blood lead concentration, and even readings as low as five micrograms/decilitre can be linked to decreased intelligence in children as well as behavioural difficulties and learning problems.
Leaded petrol was completely phased out in Australia in 2002 due to its effects on human and environmental health.
Nowadays, federal health advice says any blood level above five micrograms/decilitre should be investigated and reduced, particularly if the person is a child or a pregnant woman.
In Port Pirie, just 39.2 per cent of children tested had levels of five or below in 2020 – a 4.4 per cent decrease compared with the same time in 2019.
The number of children with levels at or above 20 micrograms/decilitre increased from 13 in 2019 to 16 in 2020.