AquaMedix founder, Brady Benson.
Legionnaires’ disease is a killer but it was only identified as late as 1976 when 34 people died at an American Legion conference in Philadelphia. Then, in March 1999, an outbreak in the Netherlands saw 318 people became ill and at least 32 people died.
Up to 18,000 cases of Legionnaires’ disease occur each year in the United States, according to the Bureau of Communicable Disease Control. The legionella bacterium can thrive in water systems including air conditioning units, cooling towers, ice-making machines and showers and taps (faucets.)
According to the Centers for Disease Control and Prevention (CDC), treatment for waterborne diseases costs over $500m in the U.S. Monetary awards for gross negligence can run into hundreds of millions of dollars. For example, after exposure to legionella in the Las Vegas MGM Hotel, eight guests filed a $330m lawsuit in 2012.
Legionella was not detected from water samples collected from hand showers fitted with the filters over the course of 90 days.
It was in Europe that a lot of research has been carried out and, according to Brady Benson, founder of AquaMedix, the U.S. did not look at the issue until comparatively recently.
“Europe is 10 years ahead and the UK has the most draconian legalities – if you are a building owner there is the possibility of you being prosecuted, whereas there are financial penalties elsewhere,” said Mr Benson.
Testing closer to European standards was carried out in the U.S. which led Mr Benson to set up AquaMedix to develop filters for showers and faucets (taps) that testing has shown removes 99.9999% of bacteria even with high flow rates according to ASTM standards.
The use of Point-of-Use (POU) filtration can be used as a stand-alone control method or in combination with other secondary water treatment methods such as chemical disinfection. POU filtration provides immediate control in a bacterial outbreak. Chemical disinfection is not always completely effective against Legionella.
“We have done a lot of work on specialized materials and came across a Belgian company called Prime Water. They have micro-filter membranes which they have been using for 14 years and we have adapted the technology for the U.S. market, making it fit with government requirements,” explained Mr Benson.
CleanSpray filters can be used for a maximum period of up to90 days before replacement is necessary.
The AquaMedix CleanSpray Micro-Filters use highly efficient asymmetrical hollow fiber membranes. These have a high affinity for water thanks to a blend of polymeric and mineral components and only require normal potable water pressure to operate the filtration process.
They operate by water flowing from the outside to the inside of the filter, a process known as dead end filtration. Filtered particles are then captured in the porous membrane wall and bacteria are captured in the hollow fiber membrane, allowing clean and filtered water to flow. The filters are also pressure resistant up to six bar and heat resistant up to 60 C if applied in a polysulfone housing.
Mr Benson states the hollow fiber membrane lasts longer than a traditional filter membrane and produces a higher flow rate.
“Bugs (bacteria) can multiply anywhere in a potable water system if the conditions are right, such as in biofilm. Biofilms occur naturally in potable water systems, providing an environment for bugs to grow. By having a filter where the water exits the system, at the Point-of-Use (POU), bugs are filtered out of potable water.”
Products include filters for hand and wall showers and a tap filter was launched on the market last September. Key markets include health clubs, schools, hotels, resorts and medical facilities. A faucet fitted with a filter will cost $176 and showers $164. Replacement filters cost $116 with a life of up to 500 to 1800 gallons and a maximum of 90 days use.
A recent report from the Special Pathogens Laboratory in Pittsburgh and the Department of Civil and Environmental Engineering at the University of Pittsburgh showed that Legionella was not detected from water samples collected from hand showers fitted with the filters over the course of 90 days.
The study was led by Dr Janet Stout and Dr Radisav Vidic at the Department of Civil and Environmental Engineering, University of Pittsburgh.
“We approached Dr Stout two years ago and explained what we were trying to do. She has worked with other filter companies and over the course of a year we tested a number of products and housing systems before taking very specific studies, the results of which have been very encouraging,” said Mr Benson.
“This study means a lot to us. We have someone from a US university validating and putting together a report to say the product does well. “
The results of the US university study allow for AquaMedix CleanSpray filters to be used for a maximum period of up to 90 days before replacement is necessary. The European standard for filter life is a maximum of six months.
Point-of-Use filtration is expected to increase due to a proposed American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 188P. The proposed standard will affect the maintenance and risk management responsibilities of building owners, engineers and managers by requiring them to have water safety programs, making them responsible for the safety of all water systems in their buildings. These standards have historically been incorporated into state and local regulation and laws. As a result, the potential market for AquaMedix is significant.
The U.S. Veterans Health Administration (VHA) has already issued VHA Directive 1061. This Directive: “… establishes policy for the prevention and control of healthcare-associated Legionella disease in VHA-owned buildings in which patients, residents or visitors stay overnight.
“We are rolling this out with the main focus being health care facilities, because they understand the products and risks,” said Mr Benson. That will be followed by institutional and commercial facilities as awareness and the implications of Legionella and other waterborne bacteria are more widely realised.