New research has found that Australians risk lead contamination from eating eggs from hens living in backyards.
Eggs from the home-kept hens contain, on average, more than 40 times the lead levels of commercially produced eggs, a Science Direct journal said.
The study found almost one in two hens had significant lead levels in their blood.
And around half the eggs analysed in the study contained lead at levels that could pose a health concern for consumers.
Even low levels of lead exposure are considered harmful to human health and can cause cardiovascular disease, decreased IQ and kidney function.
The study measured trace metals in garden soil across more than 7,000 homes.
More than 25,000 samples were collected with the study mapping the worst locations across Sydney, Brisbane and Melbourne for high lead values.
Veterinarian research indicate levels of 20 micrograms per decilitre or more may harm bird health.
In the Sydney study, 69 backyard chickens were analysed, finding 45 per cent had blood lead levels above 20.
The amount of levels depends on how much is in your soil, which vary depending on the Australian city.
Most lead gets into the hens as they scratch in the dirt and peck food from the ground (pictured, stock photo)
In older homes close to city centres, contaminated soils can greatly increase people’s exposure to lead through eating eggs from backyard hens (pictured, a graph showing lead in soil across Sydney
Analysis of homes in major cities showed most high levels of lead in the soil were in places close to the CBD.
Lead typically gets into the hens’ bloodstream when they scratch in the dirt and peck food from the ground.
And it has proven to be a major contaminant of more than 25,000 garden samples from Aussie gardens.
Research found potential contamination from drinking water and commercial-feed supplies in some samples but it was not a huge source of exposure.
Unlike humans, there are no guidelines for blood lead levels for chickens or other birds.
And there are no food standards for trace metals in eggs in Australia and globally.
Eggs from home-kept hens contain, on average, more than 40 times the lead levels of commercially produced eggs, the study showed (pictured, store-bought eggs)
It will come as a shock to Aussies who have turned to backyard food production, which has been on the rise over the past decade – spurred on by recent grocery price rises (pictured, a stock photo)
And it has proven to be a major contaminant of more than 25,000 garden samples from Aussie gardens (pictured, a graph showing Melbourne’s levels)
Deeper analysis of the data showed older homes were much more likely to have high lead levels across soils, chickens and their eggs.
It matches other studies that found older homes are most at risk of legacy contamination from the former use of lead-based paints, leaded petrol and lead pipes.
It will come as a shock to Aussies who have turned to backyard food production, which has been on the rise over the past decade – spurred on by recent grocery price rises.
Residents want to know where their food comes from, enjoy the security of producing food with no added chemicals and feel the closer connection to nature.
While urban gardening grows in popularity, the garden soil study shows it should be done with caution.
Contaminants have built up in soils over many years in Australia, especially in cities with an old industrial history.
These legacy contaminants can enter our food chain via honey bees, กินคลีน chickens and vegetables.
Hen owners in inner-city locations are advised to get their soils tested.
People can do this via community soil program VegeSafe or through a commercial laboratory, where problem soils can be identified and replaced and chickens kept to areas of known clean soil.
Hen owners in inner-city locations are advised to get their soils tested (pictured, a graph of Brisbane soil contamination)