Using a statistical model, it is possible to make reliable predictions concerning the degree to which substances are removed in the water treatment for the production of drinking water. This is a conclusion of research done by KWR Watercycle Research Institute. In the QSAR (Quantitative Structure Activity Relationship) model, a relationship is established between substance properties, such as molecular weight and water solubility, and the degree to which the substance is removed during treatment. QSARs are already frequently used in chemistry, but their application in water technology is new. “It’s a solution for the water companies, which can’t possibly test, during the water treatment itself, for all the hundreds of new substances that are discovered in water every year,” according to researchers Bas Wols and Dirk Vries.
Vries presents the conclusions of the research on 20 September during the IWA World Water Congress & Exhibition in Busan, South Korea. He expects a lot from the application of QSARs. “New methods of analysis are leading to the discovery of more and more chemicals in water – take, for instance, pharmaceuticals or pesticides. To prevent these substances from getting into the drinking water, they have to be removed during water treatment. But it is not feasible to carry out experiments for all substances. A model makes it possible to predict how well a treatment process – such as nanofiltration or oxidation using UV light – works for a new substance, because one uses data on substances that are similar to it.”
Partners sought for follow-up research
Thus, during the course of the research it turned out that metformine, an anti-diabetic drug, was not properly removed through UV/H2O2 oxidation (transformation through UV light and hydrogen peroxide). And this the QSAR had predicted, thanks to the dataset used, in which substance properties could be linked to the degree to which a substance was removable. Vries affirms that follow-up research is required to learn more about the similarities between particular substances and the process characteristics of different treatment technologies. He is therefore also seeking collaboration partners to closely scrutinise both the prediction value of QSARs for other treatment processes – such as filters with activated carbon – and a collection of substances. “The EU and governments are currently hammering away at the fact that we need to have more data about the toxicity of substances in water. QSARs now can make an essential contribution to the European regulation on chemicals, REACH. Such a conviction was still lacking, however, regarding one crucial step in the water cycle, namely, water treatment.”
Presentation IWA Busan 2012
Dirk Vries makes his presentation, “Modelling the water treatment efficiency of emerging contaminants by QSARs”, on Thursday, 20 September, at the IWA World Water Congress & Exhibition in Busan, South Korea. You are warmly invited to attend this presentation. For more information, please contact Hans Ruijgers (0031 – 6 218 228 12)
There will also be a workshop, Towards a global platform for the prediction of the removal of emerging substances from water. This will be a two-day workshop from January 31 until February 1, held at Nieuwegein, The Netherlands. For more information, see the leaflet or contact Dirk Vries.