[LUM#12] Using plants to clean up pollution

Published on July 21, 2020 in Science-Society

Pauline Adler is at the bedside of polluted soils, healing them with... plants. Her research work on the frontier between chemistry and ecology has earned her the "l'Oréal young talent prize for women in science"..

These are barren, raw lands. Nothing remains of the plant cover after an industry razed the land to the ground to exploit its precious minerals. Nothing left... or almost nothing. " On these former mining sites, you can actually find certain plants growing on soil that is toxic to most of their congeners," explains Pauline Adler.

Phyto-extraction

At the Bio-inspired Chemistry and Ecological Innovations Laboratory, the young researcher works with Claude Grison to study these special plants, known as metallophytes. "These plants are also known as heavy metal hyperaccumulators: they are capable of extracting and storing substances such as nickel, manganese and zinc. This is known as phyto-extraction.

Pauline Adler considers these properties to be invaluable. " We use them to restore these former mining sites, where they are useful in two ways. On the one hand, these plants help to revegetate these bare soils at the mercy of erosion and stabilize them to prevent wind and rain from dispersing these toxic particles. "On the other hand, their hyperaccumulative properties literally depollute the soil of these heavy metals.

Ecocatalysts

Because zinc, manganese and nickel, once captured by plants, remain trapped in their leaves. This is where the chemists come in. "What' s special about our work is that we are able to recover these heavy metals in order to valorize them, for example, by using them in the chemical or pharmaceutical industries, where they serve as catalysts for numerous chemical reactions ", explains the researcher. These " eco-catalysts " have a bright future ahead of them in today's circular economy.

Pauline Adler and her colleagues are now tackling a new challenge: water decontamination. " Certain aquatic plants also have phytoaccumulative properties, and we're counting on them to decontaminate aquatic systems, as in New Caledonia, where rivers are polluted by nickel from mining sites ".   

Key words : Chemistry, Ecology, Environment, LUM#12, LUM Magazine, Research, Science