Dozens of native birds and flying foxes have been killed by “acute” lead poisoning in the South Australian regional town of Port Pirie, with contamination fears in the town that is home to one of the world’s largest lead smelters.
Earlier this year locals in the 17,600-person town raised the alarm when they began to find dead native birds and flying foxes in large numbers in parks and green spaces, with subsequent testing of several animals showing they died from acute lead poisoning.
Pictures of dead and sick animals had been posted to social media asking for more information, with some initially speculating it may have been the result of bird flu. Some users reported they had buried the animals after they found them.
A post by the Port Pirie regional council on Instagram in August advised anyone who found three or more dead or dying birds in a single location to report the find to the Animal Disease Hotline for investigation.
It is unclear how many animals were affected but a spokesperson for the Department of Primary Industries and Regions, South Australia (PIRSA) said there were 14 reports of sick and dead birds in Port Pirie between 24 July and 14 September.
Two lorikeets, a honeyeater and three grey-headed flying foxes were sent for laboratory testing that ruled out avian bird flu or any other virus and confirmed the animals died from lead poisoning.
“Subsequent testing determined acute lead toxicosis as the cause of death of these animals,” the spokesperson said. “Further analyses concluded the animals likely had direct access to a source of lead causing an acute process, rather than a slow accumulation that developed over time.”
Having ruled out disease, PIRSA informed South Australia’s Environment Protection Authority about the results for “potential investigation into sources of lead attributable to this case”.
An EPA spokesperson said PIRSA notified the agency in October about the deaths but it had not opened its own investigation into the source of the contamination.
“The EPA was made aware of this incident by PIRSA, in supporting PIRSA’s investigation the EPA has been unable to determine the source of the lead identified in the birds,” they said. “The EPA is unaware of any further cases.”
Wayne Boardman, an associate professor of wildlife, biodiversity and ecosystem health at the University of Adelaide, said the matter should be fully investigated.
“The fact that so many animals died and the fact there has been acute lead toxicosis, that’s really a canary in the coalmine from my perspective,” Boardman said. “For me, it could be a significant public health issue.”
Boardman said it could be possible to identify the potential source of the contamination, as the animals affected were nectar-feeding birds and flying foxes.
“It seems to me, to get acute toxicity, which is rare – very rare – these days in Australia, they would have to ingest quite a lot of lead quickly, over a short period of time,” he said. “And what about the sub-acute toxicity? We see a few dead, but there are probably more with lead in their system that aren’t dying yet.”
The Port Pirie council was contacted for comment.
Testing of lead levels in the blood of children living in Port Pirie in 2021 found the highest concentration on record in a decade.
An exclusion zone along the coast has been in force since 2020 to prevent people fishing in the area after testing of fish, crabs and shellfish identified high levels of lead. A permanent ban on taking razorfish, crabs and mussels was introduced in 2022 owing to the health risks.
Port Pirie is home to a major lead refinery operated by the Belgium-based Nyrstar that serves as the major employer in the town. It has been in continuous operation since 1889.
A Nyrstar spokesperson said the company is “aware of reports of wildlife deaths in the Port Pirie region, and the subsequent investigation by PIRSA.”
“It is our understanding that the source of lead has not been able to be determined. As a member of the community, we will remain in close consultation with PIRSA to understand if there are any further developments.”
The refinery has frequently been the subject of controversy over its environmental record and lead contamination among the local community.
In 2019, documents obtained under freedom of information revealed there had been two chemical spills. The first involved 700 litres of sulfuric acid being discharged into First Creek in January, and a second cadmium leak that occurred in 2017.
Cadmium is a highly toxic metal that forms as a byproduct during the smelting process for other metals.
The sulfuric acid leak spread through a kilometre of human-made waterways until it entered nearby creeks and mangroves where it may have contributed to a fish kill.
Nyrstar was fined $35,000 in a civil penalty by the environment, resources and development court in August 2021 over its role in the spill.
