[LUM#12] Cleaning up pollution with plants

Published on July 21, 2020 in Science-Society

Pauline Adler is at the bedside of polluted soils, which she heals with... plants. Her research work at the frontier between chemistry and ecology has earned her the "L'Oréal Young Talents Award for Women in Science.".

These are arid, barren lands. Nothing remains of their vegetation cover after an industry that razed everything to the ground in order to access the soil and exploit the precious minerals it contains. Nothing left... or almost nothing. "On these former mining sites, we actually find certain plants growing on soil that is toxic to most of their counterparts," explains Pauline Adler.

Phyto-extraction

In the bio-inspired chemistry and ecological innovation laboratory, the young researcher is working with Claude Grison to study these unusual plants, known as metallophytes. "They are also said to be hyperaccumulators of heavy metals, capable of extracting and storing substances such as nickel, manganese, and zinc. This is known as phyto-extraction."

These properties make them valuable in Pauline Adler's eyes. "We use them specifically to restore these former mining sites, where they serve a dual purpose." On the one hand, these plants help to revegetate bare soil that is vulnerable to erosion and stabilize it to prevent wind and rain from dispersing toxic particles. "And on the other hand, their hyperaccumulator properties literally enable them to decontaminate the soil of these heavy metals."

Ecocatalysts

Because zinc, manganese, and nickel, once absorbed by plants, remain trapped in their leaves. This is where chemists come in. " What makes our work unique is that we are able to recover these heavy metals and repurpose them, for example in the chemical or pharmaceutical industries, where they serve as catalysts for numerous chemical reactions,"explains the researcher. These "ecocatalysts" have a bright future ahead of them at a time when the circular economy is gaining momentum.

Pauline Adler and her colleagues are now taking on a new challenge: water purification. "Certain aquatic plants also have phytoaccumulative properties, which we are relying on to decontaminate aquatic systems, such as in New Caledonia, where rivers are polluted by nickel from mining sites."   

Keywords: Chemistry, Ecology, Environment, LUM#12, LUM Magazine, Research, Science