reverse osmosis filters

In 1959, UCLA in California developed reverse osmosis (ro) with the first plant producing 22 m3 per day in 1965.  This industry now has 3,000 RO plants, each producing 4,000 m3 of drinking water daily.  Reverse osmosis is commonly used for domestic ‘point of use filtration’ for very safe, high purity water on tap, avoiding journeys to buy water and the high land fill waste of water bottles.  The domestic annual use of a reverse osmosis system along with a water softener allow combined energy and carbon foot print savings equal to the annual carbon foot print of the average family saloon car.

Reverse osmosis filter systems employ cross flow membranes, some with autoflushing, many using booster pumps.  Pre-filters are changed every 1 to 2 years depending on local water conditions.  Reverse osmosis membranes generally last between 2 to 4 years depending on the water used and can be tested at anytime for performance.  They work best on water free from iron and manganese.  Overly high incoming water pressure should be regulated.  Booster pump RO systems provide higher quality water than equivalent unpumped systems and give the most reliable water delivery.

Reverse osmosis filter systems are the only domestic filter systems able to remove impurities at full hyper-filtration levels employing up to a 10,000th of one micron filtration.  Properly specified reverse osmosis filter systems provide chlorine removal at over 99% and cryptosporidium removal to extremely efficient levels.  Benefits of reverse osmosis are the efficient removal of sodium, toxic metals, nitrates, fluoride, cryptosporidium, bacteria and an extensive list of harmful parameters found in water.

As a guide to how the average pore sizes (the tiny holes in RO cross flow membranes) compare to the size of bacteria and cysts, take the eye of a needle say 1mm in size as being the RO membrane pore sizes, then you can compare E.coli bacteria or Cryptosporidium cysts as being the size of very large hot air balloons between 15 to 30 metres in diameter.

The "Mineral Debate" and comments about "Buyer Beware" RTE December 2008.

On occasion, figures from the broader environmental sciences have debated the lack of classification for minerals in long established and recent EU Drinking Water Directives.  In all European mains supplied tap water or even in sales of bottled water, there are no guidelines to minimise or maximise mineral levels.  Packaging guidelines as to the labelling and naming of bottled mineral and spring waters exist, although many substances like sodium, sulphates and heavy metals usually limited in tap water, have practically no limits in bottled water.

One isolated Soviet era publication in the early 1980's by two Russian scientists, universally condemned by western water experts as being a short six page appendix of another larger but different type of study, used dog and rat studies without reporting important measurements to quantify the health effects of water borne minerals.  Previously the background to this study was used by other Eastern European scientists to bolster opinions within the W.H.O. (World Health Organisation) but later the ideas were discounted as highly questionable.

One well established technology; reverse osmosis with a rock solid 40 year track record of producing safe and highly potable water, often dispenses a mineral content similar to many well known bottled spring waters when plumbed directly from hard water.  Also the use of reverse osmosis plumbed after a water softener, still provides extremely safe water with ultra low sodium content usually between 1/20th to 1/40th of strict EU, EPA and HSE water testing limits.

One good reason for using reverse osmosis systems, is the ability to produce exceptional water quality, by meeting and substantially exceeding the water quality parameter limits set by  1) The European Union Drinking Water Directives,  2) The Irish EPA water parameter testing limits,  3) The Irish HSE, and 4) The World Health Organisation.

A high level of confused reporting of water quality issues and water testing issues was aired in the "Buyer Beware" programme by RTE in December 2008.  Although the programme set out to make a well presented focus on the unethical sales tactics of certain water filter products, the programme unfortunately steered off course into some very grey pseudo science with technically imaginative opinions regarding well established water treatment technologies and mineral composition in water.

The failure of the programme makers to address legislation regarding EPA and HSE water testing criteria, was very clear as they seemed to straddle EU directives by picking and choosing water testing limits and ignoring the appropriate EU directives.  However, RTE's original remit was profoundly noble in questioning and investigating the sales tactics of one particular company using emotional scare tactics to sell a crazy priced product with a bulk buying price of not far from 100 Euros or so, being sold on for well over 2,000 Euros.

Unfortunately, the programme makers approach can mean that water tested as contaminated on private wells and some schemes that many clients want to make safe, may now be incorrectly treated or subject to inferior treatment means because of the confusion generated in the public eye about the validity of water treatment systems.  The inexperience of the programme makers in turning science upside down and shaking the sense out of it, may end up threatening health rather than trying to address it.

Potentially, all Irish water treatment suppliers of popular drinking water systems were questioned, especially suppliers of reverse osmosis - one technology guaranteed to provide safe water that passes all the strictest legislation.  RTE appeared to confine the public to less avenues to safe drinking water with no ultimate suggestion of safe sources.  The Irish EPA disagree with any deviation from the understood drinking water quality legislation, which RTE on this occasion clearly sidelined by contradicting the EPA and the EU's clear objectives.

The RTE interviewed scientists were speaking about matters well out of their professional comfort zone and effectively planted ideas in the minds of viewers giving the impression that all domestic RO water filter appliances were able to perform above a level that they are actually designed for but then suggested possible risks in using them without making these risks exactly clear - possibly suggesting hyponatremia in the way that endurance athletes are exposed to by over hydrating without maintaining an isotonic balance of sodium levels or patients on low sodium diets or those with vitamin D deficiencies.

Although the company in question were offering a domestic zero TDS type of RO system, the common sense factor seemed to take a nose dive later in the TV show and it was very clear the programme makers and scientists actually knew very little about domestic reverse osmosis and the real facts and figures about water potability and water testing legislation.  Other false assumptions then prevailed in the programme which were later questioned by many water specialists who saw this irresponsible reporting as being the talk of confused amateurs.

RTE seemed to raise doubt on all RO manufacturers which would include General Electric and Siemens in both the domestic and industrial domains - world leaders in RO technology.  RTE later listed an apology on their website to one Dublin based company selling distilled water to health clubs and gyms and paid them an out of court settlement of 10,000 Euros.

Companies like GE and Siemens understand the respective application of their RO technologies whilst not getting confused in thinking that the human body is as simple as a copper pipe as commentators on the show had seemed to portray.  GE and Siemens understand the need to balance RO water after treatment with regard to water corrosivity (low langelier) when used in pipework systems, at the same time they do not compare the human body to metal pipework.  RTE was lucky not to be put into bankruptcy by these industrial giants if it was suggested their well proven water technologies were other than safe.

The public may be forgiven for getting confused about the technical issues, but not the scientists on the show.  The scientists also ignored the issues of in-organic calcium in water being  less effective than organic calcium in food, also our body's complex hyperstasis systems, the high calcium foods that we regularly eat, vitamin D as a factor of bodily calcium absorption, high TDS in saliva, variations in stomach acidity and the absorption of organic minerals depending on age.

They ignored the fact that low mineral bottled waters like Volvic are very similar to RO water and millions of consumers over decades drinking Volvic and the forty year solid track record of millions of users of reverse osmosis systems with zero reported health effects.  In short, the scientists while being technical in certain fields like microbiology, were not water experts as suggested, have no accreditations to suggest they know basic issues regarding domestic reverse osmosis systems and were talking well out of their professional remit.

The programme also suggested to more or less forget about public water testing - they confirmed it cost three to four times more than it actually did cost at the time of making the programme, from many HSE certified labs - and instead suggested drinking the likes of Cork tap water (that was easily able to fail EU testing limits for fluoride), as mentioned on the programme.  Yet the TV presenter quoted Cork City as having "Ireland's finest water".

An article, compiled by Nicola Commins, Seán Lyons and Richard J.S. Tol, appears in the Quarterly Economic Commentary, Summer 2009, published July 16.  The authors report that in 2007, the fraction of people, by county, whose drinking water failed to meet EU regulations ranges from 52 percent in Cork North to 100 percent in urban areas.  Using water quality as a parameter to show the same data, the organization reports that in 2007, 35 of the 48 standards were breached by at least one sample of Irish drinking water.  For example, more than 60 percent of the people who were supplied with drinking water in 2007 were supplied water that did not meet the EU quality standard for coliform bacteria.  “At first sight, these results are alarming.  There are substances in Irish drinking water that make people ill,” the authors wrote.

Mineral water, (by definition - water molecules that contains dissolved material) is water that usually contains at least 250 parts per million of dissolved solids, or for every 3999 water molecules, there is one impure atom of some kind, and typically from 0 to 250 ppm of dissolved solids for spring waters.  Impurities found in mineral water and borehole water such as sulphur, give water a rotten egg odour and taste.  A mineral can also be defined as any solid containing a uniform structure such as rock.

By definition, mineral water is impure.  These impurities can add a foul taste and depending on the dissolved mineral and can even be unhealthy (eg. lead, arsenic, sulphates, etc.).  Also by definition pure water is a much safer water that is essentially just H2O molecules without colour, taste or odour.  When minerals are introduced into water they can often mask the taste of underlying impurities that are not so desirable to the human body.

We require a certain amount of trace minerals to maintain our health, certainly.  However, organic trace minerals found in safe composition in foods are needed in such small quantities that anyone with a balanced diet will have absolutely no need to risk gaining other minerals, and often higher risk impurities using mineral waters that exceed safe tap water limits at the same time offering very little usable mineral content even in the highest laden mineral water.

Given the uncertain composition of various types of mineral and spring waters, there may be practically no mineral content such as in some spring waters and other mineral waters heavy in impurities can exceed EU Drinking Water Directives (for impurities set for tap water) by margins of 200%, 300%, 400% and more.  Many of these are listed on MineralWaters.Org

The truth is that people develop a powerful belief subconsciously that they can do something very simple to improve their health.  However, by drinking mineral waters with higher exposures of unsuitable trace elements, you can be taking a significant risk.  You may have no idea of the identity of the dissolved impurities, and all too often bottled waters fail simple microbiological testing, year after year in high percentages.

As for the taste of water, pure water should have no taste, and to really add some flavour to water we usually need to add concentrations of flavour additives such as fruit concentrates and sugars at levels of up to 15% to 20% of total content or in the range of 150,000 to 200,000 ppm.  As spring and mineral composition is in the range of usually 0% to 0.05% or 0 to 500 ppm, at these levels, the effect of taste is really insignificant, there are no calories, vitamins or any real nutritional content, so it is more a question of avoiding bad tastes and impurities, not so much whether taste masking minerals are present.

A safer and more cost effective approach to drinking water in Ireland is to drink filtered water.  You'll be drinking a much purer, healthy water, without taste and odour causing impurities and without ingesting potentially dangerous dissolved solids of an unknown origin.

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