Using ultrasound and algae against heavy metals
The combination of ultrasound and genetically modified algae is intended to remove heavy metals from contaminated sea sediments, according to American scientists.
Linda Weavers of Ohio State University and her colleagues had found that ultrasonic waves dislodged heavy metal compounds containing mercury from sediment grains. In order to get the free heavy metals out of the water, the researchers also made use of the natural ability of certain algae to absorb heavy metals. With the help of genetic engineering, the researchers were even able to increase this algae property many times over.
Laboratory tests showed that the combination of ultrasound and the genetically modified algae removed thirty percent of all mercury from the sediment within minutes. It was also shown that the algae used did not absorb all metals randomly, but specifically heavy metals.
This could lead to new solutions in environmental technology in the future. With appropriate filter systems, for example, the soil of shipping lanes contaminated by toxic ship paints could be cleaned without simultaneously extracting metals that are important for the ecosystem, such as sodium, calcium or iron, according to the scientists.
