Background Legionella bacteria – the cause of Legionnaires' disease – are classified as a public health risk of environmental origin. The bacteria are found in natural aquatic environments and is most common in warm countries such as those of the Mediterranean. Some of these waters are used as a source for drinking water in cities, which means that the bacteria enter the water distribution systems. Legionella is frequently found in public water supplies as well as irrigation water. It can even enter hospital water supplies – if it is not treated first – and any systems reliant on water, including those that transfer a mass of water within an air current. One of the reasons the bacteria are so dangerous is that they reproduce rapidly given the right conditions. Legionella is a particular problem in the textile sector, where it can proliferate quickly due to the ideal humidity and warmth offered by textile factories. Inhaling the bacteria can lead to legionellosis, a serious problem for human health. This disease is most prevalent in warm regions, in particular, Alcoy, where several deaths have been recorded. The main focal points of aerosols in the Alcoy area are the refrigerator towers of the textile industry. For this reason, the AITEX (textile institute) developed the project Texlegio to provide a solution to the sector. Objectives The LIFE TEXLEGIO project aimed to resolve the Legionella pneumophila bacteria problem by validating and demonstrating in the textile sector a new technique for its eradication. It attempted to attack the root of the problem by preventing the bacteria from reaching those buildings where they can reproduce easily (with moisture and heat). Specifically, it focused on those that produce aerosols or those that transfer water mass through aerial currents, as they provide a source of infection for humans. The project would use a green bio-technology to develop advanced purification and disinfection systems to treat the water to be used in those installations and clean it of exogenous micro-organisms, particles in suspension and the organic matter that can be used by micro-organisms as food and support for the formation of biofilm. It hoped to show, through monitoring of the water input, that the process can reduce the presence of Legionella pneumophila in the water supply below 50 cfu (colony-forming units) per litre and control its proliferation below 100 cells. Preventing the bacteria from reaching the installations will reduce health risks and also the costs and environmental risks associated with later cleaning and maintenance of infected installations. Another objective of the project was to ensure the compatibility of the equipment used for disinfection with conventional bactericides such as chlorine. The expected result of the project was the development of a proposal for legal regulations within the EU that enable national administrations to reduce and eventually eliminate Legionella pneumophila bacteria in the textile sector. Results Current legal regulations oblige the use of chlorination-based prevention methods, which are harmful for the workers and for the environment, as well as corrosive for the equipment. The compulsory analysis was found to be incomplete as they do not guarantee zero-risk. The project carried out laboratory tests, the design and construction of a prototype, the testing of the prototype in a refrigerator tower of a textile company, the analysis of the existing regulations and the proposal of a new regulation. The new prototype uses a combination of UV with ozone to eradicate the water that is going to supply the risk equipment (refrigerator tower). The tests carried out proved that the solution is technically viable for the elimination of the legionella bacteria. It is, moreover, compatible with the current chlorination-based prevention and control systems as well as being much more effective and safer. The effectiveness of the treatment was monitored through the control of the bacteria at cell trace levels using PCR and RT-PCR techniques. These techniques can detect the units of cells while the analysis established by the regulation only requires a limited detection of 50cfu/L (colony-forming units per litre). The analysis of costs showed that the solution proposed is more economical. However, the main barrier found to the wide use of this method is the legal framework, which obliges the owners of the risk equipment to implement a chlorination treatment – they can be fined if they do not carry out the treatment, even if the analysis shows that the water is not contaminated with legionella. So, the Texlegio treatment, at this moment, can only be used in combination with chlorination. In parallel to the technical activities, all legal regulations concerning legionella were studied The results showed that few countries have regulations on this bacteria. The analysis of the existing legislation and the results on the study made in the technical tasks allowed the project to draft a proposal for regulation. The document set outs the main topics to be covered by a rigorous regulation. The project team has contacted the relevant authorities to present the results obtained with the prototype as well as the legislative proposal. No positive feedback has yet been obtained as the issues related with the public health need to be highly secure. The project results are highly transferable to other sectors (hospitals, industry in general) and also to other countries where specific regulation is not found. Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).