© iStockphoto.com/Jim Jurica
Should I eat the vegetables I grow in my backyard? Measuring industrial contamination Industrialisation has left much of the urban environment contaminated with a variety of heavy metals, chemicals and pesticide residues. Research by a team from Macquarie University has produced a series of maps that plot the concentrations of metal pollutants across cities like Sydney and Darwin, and towns such as Mount Isa and Port Pirie.
esults of the survey indicate the spread
range of industrial and domestic materials. The high-power, high-performance, rugged unit allows in situ analysis in a wide range of harsh environments from remote mining and exploration sites to backyards in major urban centres.
of contamination in many ways reflected the growth
The latest model Delta unit offers increased
of major cities, with the highest concentrations in
speed and improved sensitivity. It also lowers the
older suburbs. The contaminant of most concern
limit of detection (LOD) for challenging elements
across Sydney backyards is lead. It would be
such as cadmium, barium, lead, mercury and tin.
expected that there would be contamination in a
According to Andrew Saliba, regional sales
major city explained the director of the Macquarie
specialist with Olympus, the traditional use of
team, Professor Mark Taylor. “We live in an
pXRF has been for alloy identification, grading
industrial environment. We have used lead-based
ore, mineral exploration, metallurgy and mine site
petrol and paint for most of the 20th century.”
remediation. “The technology has been refined and
One technique for measuring levels of
is now often used by environmental consultancies
contaminant metals that is key to the work
specialising in contaminated land remediation and
being conducted by the Macquarie team is X-ray
recycling companies needing to determine what
fluorescence spectrometry (XRF). Simple screening
materials are in waste products,” he said.
for toxic metals is performed by placing an analyser
Macquarie researcher Marek Rouillon has been
— such as the Delta Premium from Olympus —
working to evaluate the reliability and repeatability
directly onto soil or dust. The analyser provides
of XRF analysis on environmental samples.
detection of metals for site characterisation,
Professor Taylor and Rouillon regularly present
contamination tracking, remediation monitoring
their findings at seminars, outlining the spread of
and property evaluations.
heavy metal contamination in suburban gardens in
The latest portable X-ray fluorescence (pXRF) analysers, such as the Delta Premium, have been
addition to explaining the application and relevance of the pXRF instrument for this project.
developed specifically for complete environmental
Typical ‘natural’ or ‘background’ concentrations
investigations of metal contaminants in a wide
of lead for the Sydney region are in the range 20–30
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LAB+LIFE SCIENTIST - April 2016 | 29