In the modern world, we are constantly surrounded by little particles of pollution and chemical molecules – even in our homes. Some people use artificial air filters and purifiers, but what if there was – quite literally – a greener solution?
Scientists at the University of Washington have managed to genetically modify a common houseplant, devil’s ivy (Epipremnum aureum), so that it breaks down unwanted chemicals in the air. Their creation tackles molecules of chloroform and benzene, which are too small for air filters to take on. Tiny amounts of chloroform are found in chlorinated water, like the water we shower in, and benzene is found in gasoline, so it is often present in garages.
"People haven't really been talking about these hazardous organic compounds in homes, and I think that's because we couldn't do anything about them," said senior author Stuart Strand in a statement. "Now we've engineered houseplants to remove these pollutants for us."
The modified plants break down both benzene and chloroform and use them to grow. The team looked to a protein called P450 2E1, or 2E1 for short, which is found in mammals. It converts chloroform into chloride ions and carbon dioxide, and turns benzene into phenol – all substance that a plant can use. Plants use CO2 and chloride ions to make food and use phenol to build their cell walls. The research is reported in the journal Environmental Science & Technology.
The researchers implanted a synthetic version of the gene that leads to 2E1 production in rabbits into devil’s ivy. They placed the plants into glass tubes with either chloroform or benzene gas and measured how the concentrations of these gases changed over time. They conducted the same experiment using plants that hadn’t been genetically modified to see if the new gene made a difference.
When it came to these control plants, there was no noticeable difference in gas concentrations at the end of the study. However, the modified plants managed to reduce chloroform levels by 82 percent in just three days, with it being pretty much undetectable on day six. Meanwhile, they brought the concentration of benzene down by 75 percent in eight days.
To work efficiently, the plants need to be enclosed with air fanned past their leaves. "If you had a plant growing in the corner of a room, it will have some effect in that room," Strand said. "But without air flow, it will take a long time for a molecule on the other end of the house to reach the plant."
While the concentrations used in the study were much higher than what would be found in the average home, the researchers think their special plants will reduce domestic levels of the molecules by a similar proportion. The team are now hoping to get their plants to break down other unwanted molecules, like formaldehyde, which is found in certain wood products and tobacco smoke.
Perhaps one day we’ll all have tiny, toxin-eating greenhouses growing in our living rooms.