The first half yearly analysis of Port Pirie children’s blood lead levels for 2020 shows improvement in all reported blood lead level indicators.
The Department for Health and Wellbeing’s Director of Scientific Services, Dr David Simon, said the improvements in the first half of 2020 could likely be attributed to the lower average lead-in-air levels in 2019 reported by the Environment Protection Authority (EPA).
“As the smelter was shut down for extended periods of time, the lead-in-air has remained below the EPA’s license limits which means less lead dust reaches the community and our children,” Dr Simon said.
“This closure, combined with the recent improvements in how the smelter operates, has likely contributed to our improved results but it is too early to speculate whether this trend will continue.
“Decreases in lead-in-air do not immediately impact on children’s blood lead levels as there is a lag effect and once exposed, lead takes a long time to be expelled from the body.
“Most children are also only tested once a year so we will not necessarily see any impact of lead-in-air decreases on population blood lead levels until at least 12 months after sustained low lead-in-air.
“Lead-in-air is only one of multiple contributors to children’s blood lead levels and we must remain vigilant as to where children spend their time, dry and dusty weather conditions and old lead paint in homes which can all also have an impact.”
The percentage of children who tested above the national investigation level of 5 micrograms per decilitre (µg/dL), in the first six months of 2020 has decreased by 3.2 per cent to 61 per cent compared the same time last year.
The average blood lead of those children aged 24 months in the first six months of 2020 was 6.2 µg/dL compared to 6.8µg/dL at the same time last year. This measure is considered to be a robust indicator of trends in lead exposure for the whole population.
The first half report for 2020 has also seen a 50 per cent decrease in the number of children with blood lead levels equal to or above 20 µg/dL compared to the first half of 2019.
A new 12-month interim EPA licence came into effect from 1 July 2020. This licence is intended to provide greater surveillance of emission spikes by introducing a shorter three-month averaging period for some lead-in-air targets. The annual average lead-in-air limit has also been reduced by 20 per cent in the new EPA licence.
The Department continues to closely monitor the impact of these revised limits and targets on lead-in-air and lead exposure risk in Port Pirie.
The Department for Health and Wellbeing provides voluntary blood lead screening for the local community through the Targeted Lead Abatement Program, delivered by the Port Pirie Environmental Health Centre since 1984.
The blood lead levels are measured against the National Health and Medical Research Council, which advises that lead sources should be investigated then prevented or reduced at the exposure investigation level of 5 μg/dL and that blood lead levels above 10 μg/dL can have harmful effects on a number of body functions and organs in both adults and children.
The full report can be viewed on the Port Pirie Lead Implementation Program page.