A new study emphasises the health risk of metal contaminated soils and the importance of including soil assessments in environmental approval processes for new developments.

Researchers from Edith Cowan University’s School of Science and School of Medical and Health Sciences have found that soils containing even small amounts of metals such as lead, manganese or aluminium contained strains of antibiotic resistant bacteria, considered one of the world’s most pressing health issues.

Though previous studies carried out overseas had shown a link between high levels of metal contamination in soil and antibiotic resistant bacteria, researcher Dr Annette Koenders says their study conducted in Western Australia correlates even low concentrations of metals with increased antibiotic resistance in bacteria.

According to Koenders, this antibiotic resistance in bacteria is part of a naturally occurring response to protect from pollutants or stress, especially toxic metals.

The ECU research was based on soil samples collected from 80 sites on residential properties around Western Australia, and analysed for the presence of 14 different metals. The DNA of the bacteria in each soil sample was further analysed for the presence of genes associated with antibiotic resistance.

These results also underline the importance of including soil assessments in environmental approval processes for new developments, especially that of aged care facilities or schools and childcare centres and where people grow their own food. In addition to being more vulnerable to bacterial infection, children and older people are more likely to be in contact with soil; while children may crawl and play on the ground, older people spend a lot of time in the garden.

The study, ‘Relationship between antibiotic resistance genes and metals in residential soil samples from Western Australia’ was recently published in Environmental Science and Pollution Research.

Download the research here.