Water is a building block of life. Up to 60% of the human body is water. In the second part of our Healthy Home and Office Blueprint series we will share everything you need to know about what you can do to ensure a clean drinking water supply for your home.
Access to clean, non-pollutant water is crucial for your overall health and well-being but despite of advanced treatment technologies it can be still challenging to find water that is free from contaminants. Tap water for example can be polluted by inorganic contaminants, such as asbestos, lead, mercury, pesticides, and organic contaminants, like parasites, and disinfectant. The discovery of water contamination in one housing estate in Kowloon in 2015 triggered an investigation that confirmed lead and nickel contamination in numerous other estates, schools, and public buildings. Hong Kong’s Water Supplies Department has established extensive water treatment systems to assure consistent, high-quality drinking water that conforms to all drinking water standards set by the World Health Organization (WHO). So, in theory, we should all enjoy fresh and clean tap water without having any concerns over quality. However, there are risks of contamination due to Hong Kong’s drinking water infrastructure. From the treatment facility water must travel through building pipes and storage tanks. The source of contamination in 2015 was illegal welding at the joints of the water pipes that led to lead entering the water supply. Poorly maintained plumbing, water tanks, rusty pipes and pumps can also negatively affect water quality. Therefore, we would strongly suggest the installation of water filtration systems especially in buildings built before 1995.
The case against boiling your tap water or buying bottled water
Boiling your water or buying bottled water are by no means sustainable, affordable, or necessarily safe. While boiling water removes chlorine and kills some bacteria, viruses, fungi and other organisms, it’s not only energy-intensive, but it also does not eliminate heavy metals from your water. Heavy metals are the main contaminant found in Hong Kong tap water.
Purchasing commercial bottled water contributes to immense material waste. It takes a plastic water bottle over 1,000 years to bio-degrade. Furthermore, the global bottled water industry consumes millions of barrels of oil and produces incalculable litres of wastewater in the production of marketable bottled drinking water. Successive studies by the Hong Kong Consumer Council have debunked the notion of commercial bottled water as a healthier alternative to filtered tap water. A 1998 Consumer Council Test Report sampling 30 commercially-available brands of bottled water determined that ‘most bottled waters do not possess any greater health properties than plain tap water,’ and that ‘some bottled waters may even contain traces of impurities.’ In some, dangerous contaminants such as lead, arsenic, and nitrate were discovered. The only viable solution is the installation of a home or office water filtration system that removes all impurities from tap water.
What different water filtration systems are there?
Each water filtration system has advantages and disadvantages. In the following, we are looking at the most common ones.
1. Reverse Osmosis
Reverse Osmosis water filtration is a process in which water passes through a semi-permeable membrane that filters contaminants out of the water, producing purified drinking water as a result. Most reverse osmosis systems consist of a multi-stage purification process incorporating activated carbon filters along with the RO membrane itself to assure a highly purified water quality.
- Advantages: Reverse Osmosis Filters remove a very wide range of contaminants, including dissolved solids. Additionally, they are the only filters certified to remove arsenic.
- Disadvantages: Reverse Osmosis Filters are very expensive. Furthermore, they are often slow, bulky, and immensely wasteful – producing up to 7 litres of wastewater for every 1 litre of drinking water produced. A Reverse Osmosis system set up to serve an entire household could easily discharge over 1500 liters of wastewater per day. They also require a water pump to be installed to increase water pressure which increases electricity costs. In addition, reverse osmosis systems completely strip tap water of mineral content, resulting in water that some studies suggest can pose health complications of its own. The World Health Organization (WHO) has investigated the health effects of demineralised water since 1980. Experiments in humans have found that demineralised water increased diuresis and the elimination of electrolytes, with decreased blood serum potassium concentration. Magnesium, calcium, and other minerals in water can help to protect against nutritional deficiency.
Reverse Osmosis systems are aggressively marketed in Hong Kong and sales reps of many RO companies are using a scam to trick you into buying their pricy filtration systems. Sales reps come to your home and perform a free tap water test. They then use a ‘electrolysis test’ to compare your tap water against the water produced by the RO water filtration system. The electrolysis process turns your tap water, with its high dissolved mineral content, into a brown, bubbling froth while the filtered water stays in its original state and looks clean. A sales representative then claims that the colour and particles in the water proves just how contaminated your tap water is.
However, all this test shows is the conductivity of minerals like magnesium, calcium, and other dissolved substances, which in fact are critical for human health. Moreover, contaminants like bacteria, viruses, and heavy metals are non-conductive and thus their presence would not be revealed by such a test. Hence, the test only shows that the filtered water is free of essential minerals but by no means free of contamination. Watch a complete demonstration of how the electrolysis scam is perpetrated:
2. Activated Carbon
Activated Carbon filtering uses pieces of activated carbon to remove contaminants and impurities. The activated carbon chemically absorbs impurities in the water.
- Advantages: Activated Carbon filtering is the least resource-intensive of all commercially available filtration options, and in addition has very high filter efficiency (filtering most organic and inorganic compounds as well as bacteria and viruses). Additionally, Carbon filters are the most effective option for removing chlorine, sediment, and volatile organic compounds (VOCs) from water.
- Disadvantages: Activated Carbon Filtering is not effective at removing salts and some dissolved inorganic compounds.
3. UV Treatment
Ultraviolet Treatment refers to the use of ultraviolet light to disinfect water or reduce the number of heterotrophic bacteria present in the water.
- Advantages: UV treatment is rapid and, in terms of primary energy use, approximately 20,000 times more efficient than boiling.
- Disadvantages: UV treatment only disinfects, and hence does not filter any sediment out of the water. Therefore, it must be combined with other filtering techniques to guarantee purified water.
4. Microfiltration / Ultrafiltration
These filtration methods can be understood as physical sieving separation processes. Water flows through a membrane with a pore size of 0.1 to 3 microns in the case of Microfiltration, and 0.01 to 0.1 microns in the case of Ultrafiltration. Thus, Microfiltration is suitable for turbidity reduction and the removal of suspended solids, while ultrafiltration also filters viruses, colours, and odours.
- Microfiltration Advantages: Only low pressure is needed to remove solids, some viruses, colours, and odours, meaning this process consumes less energy that RO.
- Microfiltration Disadvantages: Normally only suitable as a pre-filtration technology, which must be followed by other technologies to assure clean water.
5. Ionized “Alkalized Water”
Ionization is a chemical process, in which an atom is converted into an ion by either adding or removing charged particles such as electrons or ions. In the case of water, the water ionizing companies claim that the water is ionized through “electrolysis” resulting in water pH value >7 (or alkalized), rather than the pH value of 7 (neutral) of normal tap water. According to its supporters, the effects of this process include a slow-down of the ageing process and the prevention of disease. Electrolysis is a process by which water is separated into Oxygen (O2) and Hydrogen (H2) rather than resulting in “ionized water”. Furthermore, there is no empirical evidence to support the claims that alkalized water prevents disease or slows ageing. Thus, the effects of alkalized water are more based on belief than scientific fact.
Our recommendation for your home/office
Install an activated carbon water filtration system
An effective water filtration system filters contaminants that may have leached into drinking water from aging pipes or infrequently cleaned water tanks. Based on a review of the scientific evidence and consultation with both independent and government labs, we recommend the installation of an activated carbon filter. It is the most practical and cost-efficient solution for homes and offices in Hong Kong because
- rust, sediments, lead, and other heavy metals are filtered out, assuring that contamination caused by aging or distressed pipework is adequately absorbed. The result is safe, potable water that fulfils all WHO requirements for clean drinking water.
- activated carbon filters are the most resource-efficient filtering systems on the market, avoiding the material waste of commercial bottled water as well as the large volume of wastewater produced by Reverse Osmosis filtration systems.
- activated carbon filters are the best value for domestic and office use. Compared to other filtering systems such as Reverse Osmosis, the set-up and maintenance costs for activated carbon filtration systems are low.
There are many companies in Hong Kong that offer activated carbon water filtration systems for homes and offices. Watch out for independent third party certification for their systems and filters, e.g. NSF or UL certification. The NSF is a global, independent health and environmental organization whose Water Treatment Device Certification Program requires extensive product testing. Their certification program provides assurance to consumers that the water treatment devices they are purchasing meet the design, material, and performance requirements of national standards.
Our next article in the Vivid Invest Healthy Home Blueprint series will focus on the ‘Renew’ element of the Blueprint. We will cover how you can eradicate obstacles to well-being, such as noise and light pollution to create a sanctuary where relaxation is naturally and effortlessly achieved. If you don’t want to miss out on any of our publications please make sure to subscribe to our newsletter.
If you have any suggestions or comments please feel free to reach out to us.
- World Health Organization: “Guidelines for drinking-water quality, fourth edition,” 2011
- National Sanitation Foundation
- Underwriters Laboratories
- Water Quality Association
- World Health Organization: “Health Risks from Drinking Demineralized Water,” 2004
- NDSU Extension Service: “Reverse Osmosis,” 2013
- Hong Kong Consumer Council Press Release: “The mineral content of bottled water is either “low” or “very low” and some may even contain impurities,” June 1998
- The Water Project: “Bottled Water is Wasteful”