Microplastics—tiny plastic pieces that pollute rivers, lakes and oceans—are hard to remove from water. A research team at the University of Missouri, led by professor Susie Dai at the Bond Life Sciences Center, is testing a new approach that uses genetically modified algae to capture these particles.
The scientists engineered the algae to produce limonene, a natural oil that gives oranges their scent. Limonene makes the algae water-repellent, so the algae attract similarly water-repellent microplastics. The algae and plastics form clumps that sink and create a solid biomass layer that is easier to skim and remove than dispersed particles.
The engineered algae can grow in wastewater, where it consumes excess nutrients and helps clean the water. In the lab the team grows algae in large tank bioreactors and has built a 100‑liter bioreactor called “Shrek.” Dai hopes to scale up systems like this for wastewater treatment and other pollution removal tasks. The study appears in Nature Communications.
Difficult words
- microplastic — very small pieces of plastic pollutionmicroplastics
- alga — a simple water plant or sea organismalgae
- limonene — a natural citrus oil with orange scent
- water-repellent — does not mix with or absorb water
- biomass — material made from living or once-living organisms
- bioreactor — a tank where biological growth is controlledbioreactors
- wastewater — used water from homes or industry
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think using genetically modified algae is a good idea for cleaning water? Why or why not?
- How might local wastewater treatment change if bioreactors like "Shrek" are used?
- What are possible benefits and risks of removing microplastics with algae?
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