Plants take heavy metals like arsenic, lead and cadmium up from the soil and by consuming the vegetables we also consume those pollutants. If we want to establish a garden that can provide us with healthy veggies and herbs, it is important to deal with this risk.
Macquarie University’s VegeSafe program is surveying heavy metal pollution in private gardens. It appears that lead is the main problem. Lead was introduced into automotive fuel 1932 and withdrawn in 2002, it was also part of exterior paint until the 1970s.
The results show, that there is an increased concentration of lead close to main roads and in the vicinity of the drip lines of houses. After renovations, where paint has been stripped, the lead concentration in the soil close to these activities also often spikes.
If the soil in your garden is polluted with heavy metals, the recommendation is to:
- build gardens away from main roads
- cover polluted soil with clean soil
- build raised garden beds using clean top soil instead of old soil
- thoroughly wash fruit and vegetables
- wash hands after gardening
Testing for soil pollution
Visit the VegeSafe website to learn about their findings in regard of heavy metal soil pollution in your area.
You can also join the program and have your soil tested for heavy metals for free. Just collect some samples of soil from different areas of your property and send them to the research project. You will get a detailed report about the pollutants in your garden and some advice how to act on this.
All the necessary details can be found on the VegeSafe website as well.
Outlook: Macquarie University is planning to extend it’s research in future to also test for pollution by organic chemicals and pesticides in soil and for the accumulation of pollutants in the eggs of chickens that are living in private gardens.