Graphene could strip polluting medicines from wastewater
The team from the Aristotle University of Thessaloniki have shown that graphene - a wonder material made up of sheets of carbon a single atom thick - can remove drugs that current wastewater treatment technologies cannot handle.
Pharmaceuticals are often excreted from the human body with little or no changes to their chemical structure, finding their way into wastewater and even in some cases drinking water supplies, according to the scientists.
A lot of the environmental concerns surrounding drugs in the environment centre around antibiotics and their potential to affect wildlife and precipitate antibiotic resistance, an issue which sparked protests at the this year's CPhI conference in Madrid.
There are a number of other drug classes that are challenging to remove and have environmental consequences, however, including beta blockers that have been shown to affect the life cycles of aquatic algae, plants and insects.
Using graphene oxide (GhO) as an adsorbent material within wastewater treatment plants, the researchers were able to show that two common beta blockers - atenolol and propranolol - could be removed effectively in a manner compatible with existing processes.
Importantly, the GhO could also be recycled and re-used, which could keep costs down, they note. The research is published in the journal Science of the Total Environment (15 December 2015).
Graphene is one of the thinnest and strongest materials known and is already finding applications in drug and gene delivery, biosensors and prosthetics, as well as a host of uses in materials science outside the pharma sector.
Seeking to tap into its potential, the UK recently formed a £60m ($95m) National Graphene Institute (NGI) based at the University of Manchester to provide a single hub for research into the substance.
The Green Lobby
In addition to tackling pollution of excreted drugs, the pharma industry has also come under fire from the green lobby for the release of environmentally-damaging compounds into water systems as a consequence of API production.
Three drug substances - two oestrogen hormones and an anti-inflammatory drug (diclofenac) - were added to an EU 'watch list' of possible surface water pollutants in 2013, the first time pharma compounds had been added to the monitoring list. Industry lobbying prevented them from being added to a priority list that would have introduced stricter controls.
It is feasible that graphene could also be applied within facilities to clean up effluent, although this was not addressed in the current study.
Some API producers - including DSM-Sinochem and GlaxoSmithKline - are taking other efforts to introduce processes that reduce the environmental impact of their operations, for example by limiting the release of toxic chemicals from facilities and phasing out the use of organic solvents.
