SCIENTISTS in Hungary say cabbages could be used to monitor industrial pollution and accidental soil contamination.
While obviously very much cheaper than a commercially designed and installed electronic monitoring system, less predictably cabbages also appear to be more reliable.
Researchers from the Debrecen Agricultural University have recently completed an extensive study on 12 members of the Brassica family to assess which of them are the most effective bioindicators.
Varieties tested included red, savoy and white cabbage as well as cauliflower, Brussels sprouts and broccoli, as well as non-edible variants of ornamental cabbage.
The study was carried out in the small garden of a Hungarian cabbage fancier, which provided a ready made opportunity to assess element accumulation levels under the same conditions.
It measured accumulation of heavy metals and other elements caused simply by the use of organic fertiliser - the garden was not otherwise contaminated. Nevertheless, tests on the cabbages picked up cadmium, lead, arsenic, mercury, chromium, copper, iron, manganese and radioactive strontium.
'Since fertilisers accumulate not just the essential and beneficial nutrients but high amounts of contaminants, fertiliser can be considered a less harmful situation for modelling industrial contamination,' comment the researchers.
They aimed to find which cabbage proved the most sensitive and reliable indicator, and which part of the cabbage needed to be tested.
In some species only the stalk or roots absorbed detectable levels of the elements, whereas in others the elements could be detected in leaf samples, obviously preferably if the plant is used for long term monitoring.
In the trial all the species detected the majority of the elements identified in the fertiliser, although lead, arsenic and mercury were less reliably identified. Overall, non-edible cabbages were better at picking up these elements, while of the edible species broccoli and sprouts were marginally more sensitive than the various cabbages and cauliflower.
Chinese and savoy cabbage failed to detect lead, arsenic and mercury at the low level present in the fertiliser.
The researchers conclude that Brassica plants are efficient and cheap indicators of environmental conditions. They also point out that unlike the presence of a technician in protective overalls probing the ground with expensive looking equipment, a cabbage patch is unlikely to raise environmental concerns among a local community.