It’s no secret there is lead contamination in much of Broken Hill’s soil.
Over 100 years of mining lead does that.
Research papers, including Boreland 2002 and Yang and Cattle in 2015, have pointed out that we have high lead levels in the city, which diminishes the further from the Line of Lode you go.
Go 1000km away, in Sydney, and research just out reveals lead in eggs from backyard hens in the capital city have high lead levels.
Macquarie University’s Earth and Environmental Science department has been testing backyard chickens and their eggs for trace metal contaminants, with a particular interest in lead concentrations, as part of a project being run by PhD candidate Sara Yazdanparast.
A map produced recently as part of the study shows the closer you go to the centre of Sydney, the higher the lead in the soil.
Factors influencing Sydney could be historical remnant lead from old paint and lead from lead petrol which could have been dropped by exhaust fumes significantly when cars and trucks changed gears – think busy intersections and traffic lights.
In Sydney, they found levels of lead below 100 mg/kg, which is a safe level, and up to 697 mg/kg which is an unsafe level.
In Broken Hill back in 2015, Yang and Cattle found more than 1000 mg/kg of lead in soils 400 metres north and up to 800 metres south of the Line of Lode.
According to Yang’s research, most of the topsoil in Broken Hill in 2015 was above the safe level of 117mgs/kg.
Professor Mark Taylor, who has been overseeing the Macquarie University research, said, “If you have hens in Broken Hill, it would be a good idea to have the chicken run’s soil changed to fresh soil up to 10-15cms down and keep the chickens there.”
“The other thing to do is to ask the EPA to test the soil.”
He added if your yard has already been treated for lead, it should be ok.
Prof Taylor praised the local lead program, saying they had done a fantastic job of remediation in Broken Hill.
But the professor confirmed that only in the very outer blocks of land was the soil in Broken Hill suitable for having hens.
Luckily many Broken Hill people have had their soils treated and new soil put in.
The EPA is presently creating handouts for people in New South Wales to find out if their hens need new soil so you can eat your eggs knowing they are not lead-laden.
For a better understanding of lead in the environment over the last 25 years, go to https://www.youtube.com/watch?v=zEgLPiFKVm8 for a short doco by Prof Taylor.