VTT and Aalto University have developed a solution for capturing pharmaceutical substances from water. It is an affordable wood-based cellulose fiber yarn that absorbs hormones, such as ethinylestradiol in contraceptive pills, that would otherwise end up in rivers, oceans, or other bodies of water.
How It Works
- The researchers chemically bond cyclic sugar onto the surface of cellulose fiber yarn. Also, cyclodextrins are coupled to the surfaces and cavities of the fiber to enrapture pharmaceutical compounds.
- The sugars form pockets. Hydrophobic pharmaceutical substances seek to enter such enclosures to get away from water. When they do, the pharmaceutical compounds become bound to cyclodextrins.
- The entire process takes only a few minutes.
- They tested the material’s capacity and found that one gram of fiber yarn can capture around 2.5 milligrams of the hormone.
VTT’s Senior Scientist Hannes Orelma said:
Hormone capture would be most effective in wastewater treatment plants and hospitals since the wastewater in these facilities contains a higher concentration of the compounds. We are developing a wood-based affordable material that could be thrown into a tank in a wastewater treatment plant or used as a filter in a pipe connected to the tank. After some time, the material is collected mechanically. It is disposed of by incineration, but it is also possible to separate the pharmaceuticals and reuse the material.
VTT developed a method for manufacturing the wood-pulp-based fiber yarn by using deep eutectic solvents (DES), a new class of organic solvents. The type of DES these researchers employed is an environmentally friendly one.
At the moment, the material has only been tested out on a small-scale. Orelma said:
It would be interesting to test how effectively the cellulose yarns can capture hormones and pharmaceuticals from wastewater at a larger scale.
It has not been a major topic of discussion. Still, hormones and other pharmaceutical agents ending up in bodies of water is a big problem, especially in Central Europe and the USA. The reported concentrations of estrogen hormones in these regions has reached up to 0.83 micrograms per liter. The hormones in the contraceptive pills are known as endocrine disruptors. They affect the gender of a fish resulting in male fish turning into females.
Wastewater treatment plants can’t capture such small substances efficiently enough. The EU has already identified pharmaceuticals in water as a problem and a challenge that has to be solved. Wastewater treatment plants do capture a portion of the compounds utilizing activated sludge tanks, but a part of it escapes the tanks and ends up disrupting natural ecosystems. This research has the potential to finally change that.
