Nanomaterials and typhoons
Yesterday was my first day in Busan. A typhoon landed here, bringing a lot of rain and wind. Inside the Busan Exhibition and Convention (BEXCO) centre it was dry and comfortable, but there was a typhoon on information and presentations. Too many to attend them all.
In two workshops nanomaterials were discussed. The first workshop addressed the risks involved in nanomaterials. Nanomaterials are applied in many consumer products nowadays: over 1300 different products have been registered. Nanomaterials have special properties related to their small size, which can be used beneficially. Water treatment techniques may also benefit from these properties.
Use of these products implies that they will be released to the environment. The same properties of these nanomaterials means that they are a potential risk to the environment and human health as well. The risk is of course determined by toxicity and by exposure, and these are both often unknown factors. Qilin Li (Rice University) presented an overview of stability and toxicity data of nanomaterials and Brita Forssberg (Sweden) presented the way that stakeholders could be involved to prevent the risks. Her approach is to inform all stakeholders about the problems that can occur if harmful compounds are present in drinking water sources and to convince them to look for alternative, less harmfull solutions. During the discussion the necessity of using nanoparticles in consumer products was discussed. Why do we need silver impregnated socks if washing your feet is equally effective against odours and the silver is gone after 10 times washing? The same goes for using nanotechnology in water treatment: is it really necessary, and should we use it if we do not know the risks on release of nano-particles to the drinking water? The important conclusion was that it is very important to investigate the (long term) effects of exposure to nanoparticles before they are applied.
The second workshop dealt with the application of membrane and nanotechnology for desalination and water reuse. The presentations on nanotechnology were mostly on nanoengineered membranes. These membranes are now commercially available and tested on several locations. Miguel Angel Sanz (Suez Enviremont) showed the development of energy consumption of RO systems over the last 20 years. With the new nanoengineered membranes, the energy efficiency is approaching the theoretical minimum. And in this workshop the same question about the risk of releasing nanoparticles to the drinking water came up: an important research question to investigate the coming time.