30a Reunião Anual
Sociedade Brasileira de Química
:: Menu ::
:: Conferências Plenárias ::


Molecular Sciences, Key to Sustainability in the Water World

F. H. Frimmel
Universitaet Karlsruhe, Germany

Water is the basis for life. The limited availability is going to become a great challenge for human development. There is not only the regional problem of quantitative availability of water, but even worse the water quality issue due to growth of population, industrialisation and urbanisation. In 2050, more than 42 % of the world population will have no access to sufficient and safe drinking water. Besides the efficiency in energy utilisation, the need of sustainability in water management has grown to be the most important issue in the survival strategy of mankind.

The role of molecular sciences
The manifold usage of aquatic systems has led to a large variety of pollutants. Most of them are not visible directly and need advanced instrumentation for identification and quantification. Molecular sciences therefore have become an efficient tool not only for the characterisation of pollutants, but also for finding ways to keep them under control. This will be demonstrated by selected examples focussing on analytical, physical-chemical and engineering aspects.

Natural attenuation
The early years of industrialisation were and still are usually determined by strong economical activities and uncontrolled pollution of the environment. In the more mature phase, awareness of the essential role of resources and aspects of the quality of life gain importance: sustainability as care for the next generations and the basis for their lives begins to grow. The former mainly economical driving force gets an ecologically active component to form a socially compatible system. The basic questions: how much of ecological care is necessary and what does sustainability need are not easy to be answered. However, a good understanding of nature and its capacity to maintain its health and functions might help. Dumping areas, industrial deposits and untreated waste water are sources for toxic and poorly biodegradable substances like polycyclic aromatic hydrocarbons (PAHs), pesticides, heavy metals and their species. Analytical methods have been developed and standardised to investigate the occurrence, transport and reactions of these compounds under natural conditions including colloidal carriers.

The environment is normally much too complex for a comprehensive removal of pollutants. Therefore, priorisation is needed. Years ago detailed analytical investigations were the only way to assess the situation. In the meantime valuable methods for a bioeffect oriented evaluation have been developed, e. g. ELISA (Enzyme-Linked Immunosorbent Assay) for pesticides and their metabolites or biotests for endocrine active substances and genotoxic compounds have opened the door for a screening for biologically active compounds in all kinds of aquatic systems. In addition, the occurrence of special micro organisms and their functioning in water treatment can be monitored by FISH (Fluorescence In Situ Hybridization). These aspects add significally to an improved understanding of the fate of living and non living matter in aquatic systems and their technological use.

Pharmaceuticals as emerging pollutants
Due to broad application and partly high resistance against biodegradation, pharmaceutically active compounds have been found in surface and ground water recently. Many interesting questions on the ecological consequences arise from these findings. Iodinated X-ray contrast media can be used as tracer for leakages in sewer pipes. With respect to the water and waste water management, promising elimination methods based on advanced oxidation processes and membrane separation have been investigated. Hybrid systems with minimised resulting waste lead the way into sustainable technologies.

Sustainable water management
It is beyond doubt that sustainability must have top priority in water management. Molecular sciences can supply the necessary basis and tools for reliable diagnosis, effective treatment steps and successful concepts to safe that unique and non replaceable matter for life.

For more information: http://www.wasserchemie.uni-karlsruhe.de/