Her mission: Clean water

Regina Sommer contributed to the development of national and international standards that are applied worldwide. One of them, an Austrian ÖNORM standard, was even made mandatory by the French legislator.

ao. Univ.Prof. Dipl-Ing. Dr. Regina Sommer
ao. Univ.Prof. Dipl-Ing. Dr. Regina Sommer

Regina Sommer just received an award: She was honoured as the FEMtech expert of the month of August 2013 by the Federal Ministry for Transport, Innovation and Technology. An independent, interdisciplinary jury made up of high-level representatives of the economy, science and human resource management awarded this title to Regina Sommer. The hot month of August was a fitting data since Regina Sommer also focuses on the topic of "bathing" in her work – from whirl tubs to fun pools. The 52-year old food scientist and biotechnologist is "the" hygiene expert for water.

The internationally renowned scientist heads the accredited testing and inspection body for hygiene at the Institute for Hygiene and Applied Immunology at the Medical University of Vienna, chairs the Codex Commission on Drinking Water, serves as the president of the Austrian Society of Hygiene, Microbiology and Preventive Medicine, co-heads the Interuniversity Cooperation Centre for Water and Health Interuniversity Cooperation Centre (ICC) for Water and Health (a cooperation project of the Medical University of Vienna and the Vienna University of Technology) and, last but not least, she is a member of the Presidential Council of Austrian Standards. Here, she works in various committees on water and hygiene and chairs the ISO working group on "Clostridia" (ISO/TC 147/SC 4/WG 5). In parallel, she participates in several international research projects.

In spite of all those time-consuming activities, she takes ample time for her students. The author of this article was able to witness this himself. A diploma exam delayed the interview planned with the hygiene expert. The candidate – an obviously nervous young man – had defended his diploma theses before a jury including Regina Sommer and waited in the corridor of the Institute for the result of the jury's deliberations. Finally, Regina Sommer opened the door and asked the candidate to join the jury for a final round of questions and, finally, a new university graduate entered the medical community.

Pathogens join us for a swim

One thing is certain: Regina Sommer does not like contaminated water – neither drinking nor bathing water. The fight against unclean water has become the mission of the scientist who completed her habilitation in this discipline at the Medical University of Vienna in 1999. When many people swim together in a pool, they invariably introduce pathogens into the water. Without any countermeasures, those bacteria, viruses and parasites would infect the swimmers. Another thing is certain, too: Regina Sommer knows what can be done against them: "For swimming pools, the all-purpose disinfectant still is chlorine," she says with conviction. The circulator pumps the pool's water to the treatment system where undesirable particles are coagulated and removed from the water by a filter. Finally, a small amount of chlorine is added to the water before it is returned to the pool. "Chlorine is the most effective disinfectant for pool water and reliably destroys microorganisms," explains Regina Sommer. It is important to know that the unpleasant odour of chlorine only arises if the pool's water is insufficiently filtered and contaminants react with chlorine.

"Applied according to ÖNORM"

Scientist and teacher: Regina Sommer during a course on drinking water hygiene at Austrian Standardswater
Scientist and teacher: Regina Sommer during a course on drinking water hygiene at Austrian Standards

And how do you disinfect drinking water? You would certainly not use chlorine because nobody would like to drink that. "That is a good question," replies Regina Sommer. "Here in Austria, drinking water is mainly disinfected by means of UV radiation." Austria classifies drinking water as a "foodstuff". Accordingly, legal requirements are rather strict. In particular, the biggest issue are pesticides, nitrate and fertilizers as well as pathogens introduced by floods. Austrian water utilities primarily use UV radiation when it is necessary to disinfect drinking water. The fact that this technology can be reliably used for drinking water disinfection is also owed to the work of the UV research partners of the "UV Team Austria" around Regina Sommer (Medical University of Vienna; University of Veterinary Medicine, Dipl.-Ing. Alexander Cabaj and Dr. Alois Schmalwieser; Austrian Institute of Technology, Ing. Georg Hirschmann). The principle is simple. Drinking water passes a UV light source in a radiation chamber and, in a split second, the microorganisms are deactivated and are no longer able to reproduce and infect humans. "The great advantage of UV radiation is that all pathogens, including bacteria, viruses as well as highly resistant parasites, are reliably deactivated." And how does that actually work? "UV light damages the genetic information of the microorganisms. Thus, their reproduction is prevented and the pathogens cannot infect people anymore," explains the hygiene expert. She adds: "Moreover, UV radiation does not change the taste because it does not change the substances contained in water – if applied in line with our ÖNORM standard. In contrast, chlorine is less 'smart'. It does not distinguish between microorganisms and the ingredients of water. As a result, it may give rise to by-products that are harmful to health."

Well, but why is UV radiation not used for pool water as well? "Guess why," says Regina Sommer. And yes: To inactivate the pathogens introduced by the swimmers into the pool, you would have to expose the water in the pool and, thus, the people to radiation. It is obvious that this would be harmful to health. Therefore, pool operators rely on good, old chlorine that develops its effect in the pool's water. The Bathing Hygiene Regulation defines the requirements for water quality and permitted treatment processes, while the specifications for technical systems are laid down in related ÖNORM standards.

Mandatory in France

Let us return to the UV disinfection of drinking water. Here, a technical problem relates to controlling the effectiveness of disinfection. After all, it is not so easy to expose the entire water flow to sufficient UV light. Tests performed on dyed water show that water does not flow regularly through the radiation chamber but generates distribution patterns. Together with the UV Team Austria, Regina Sommer developed a test method for UV disinfection systems and found a bacterium whose spores can be used to measure reliably the disinfection performance of any UV system. That was not easy – maybe this is why the bacterium's name is "bacillus subtilis"?
Not least thanks to the profound work of Regina Sommer, Austria is the only EU country which has a specific national standard on this topic. ÖNORM M 5873 – whose full title is "Plants for the disinfection of water using ultraviolet radiation – Requirements and testing" (parts 1 and 2) – forms the basis for a quality label of the Austrian Association for Gas and Water (ÖVGW) and for certification by Austrian Standards. Operators of those certified installations can be sure that full disinfection is achieved.
By the way, this ÖNORM standard did what Regina Sommer wants to prevent in the case of microorganisms in swimming pools: It spread. Translated into English, it was taken over in many countries all over the world. This evidences the quality of this standard as those countries voluntarily adopted the Austrian model. Just recently, France even went a step further: The French Ministry of Social Affairs and Health declared the standard to be binding at the start of 2013. This means that UV installations for drinking water disinfection have to comply with ÖNORM M 5873 in France.

No shadow without light

Water hygiene is not a theoretical ivory-tower topic. In 2010, a tourist died from a bacterial infection contracted in a whirl tub in Salzburg. "Stagnant water in the jet hoses of the whirlpool system formed a biofilm in which bacteria were able to flourish. When you turn on the jets, bacteria get into the tub," explains Ms. Sommer. In that case, the bacterium Pseudomonas aeruginosa caused organ failure and death. However, there is no shadow without light. "This tragic death raised awareness of the risks harboured by such whirl tubs. Now, their hoses have to be regularly disinfected before use." To put this into practice, ÖNORM M 6222-1 was developed for the operation of whirl tubs. For ever active Regina Sommer, these real-life aspects are of particular importance: "We investigate and study, but we do not research in an ivory tower. What we do should have a positive impact on people's everyday lives."

Her Department of Water Hygiene was the first accredited laboratory of the Medical University of Vienna. Ms. Sommer and her team prepare water hygiene expert opinions for healthcare facilities, water suppliers, specialized companies and others. A focal area of her work is to verify the effectiveness of UV disinfection systems. Internationally, there are only four test beds for the type testing of UV disinfection systems. One of them is located at Wasser-Technikum Wiental, a joint research centre of the UV Team Austria and Vienna Water.

When so intensively confronted with all kinds of pathogens in water, how does ao.Univ.Prof. Dipl-Ing. Dr. Regina Sommer herself use water: "Well, I am careful, but I do not overdo it," she admits. "In Austria, I naturally drink tap water, but on trips to countries that do not have a hygienically reliable drinking water supply it is necessary to use bottled water."

Author: Gerd Millmann


ÖNORM M 5873 Plants for the disinfection of water using ultraviolet radiation - Requirements and testing
ÖNORM M 6222-1
Requirements for the characteristics of bath water in whirl tubs - Operation, maintenance and inspection

PR-ID: 0671-2013-09-18 / clean_water