Are household water filtration and treatment devices safe?
In the past few years we have been bombarded with reports of how bad our tap water quality is. You have probably been contacted by a sales person to show you how contaminated your tap water is. They will often suggest that you urgently need a home water treatment device to ensure safe tap water for you and your family.
This has opened up the market for the sale of home water treatment devices to consumers who often do not know or ask whether these devices have been scientifically tested or not.
Most of these units are sold over the counter and are purchased in good faith, on the basis of claims on their efficiency made during marketing and advertising campaigns, and with the expectation that the units will perform miraculously and remove at least 90–100% of all harmful microorganisms. However, the claims made in the manufacturer’s brochures are often not substantiated by independent testing. These products are usually tested in-house by the manufacturer under ideal operational conditions, and often only for their capacity to remove traditional indicator bacteria.
We need to ask ourselves whether the claims made by manufacturers regarding the water treatment efficiency of the supplied home water treatment devices have been verified and reported accurately.
An independent study recently published by the Water Research Commission (WRC) evaluated a representative sample of units sold in South Africa against the claims that are made in sales brochures. This study sourced devices from informal market retailers, direct marketers and national retail stores. None of the devices tested met all of their manufacturer’s claims.
All the devices tested did improve the water quality in terms of its aesthetic attributes such as reducing scale, but in terms of taste, odour, heavy metal and microbiological removal claims they performed rather poorly.
The greatest concern and conclusion from the study was that all the devices tested indicated that the device should only be used with treated tap water that already meets SANS241 requirements, raising the question: why there would be a need for further treatment of clean and potable water?
The South African legislation requires that all water treatment device components installed at household level are approved by the South African Bureau of Standards (SABS). However, it does not explicitly prohibit the import and sale of any products. As a result, the market has been flooded with water treatment devices which are not necessary and may even be harmful. The WRC has produced a consumer pamphlet giving guidance on the aspects to consider before purchasing a home water treatment device filter.
Choosing the best home water treatment technology for your family‘s specific needs can be a daunting task. Some basic tips can guide the users of this device. For example, chlorine levels may be higher if you are closer to the reservoir where chlorine dosage occurs. A small amount of chlorine is needed to prevent bacterial growth in pipes. Chlorine is only harmful to your health when levels exceed 5 mg/L, however, you can smell and taste chlorine at 0, 2 mg/L. Sanitation practices in your house can influence your water quality. The outlet of your tap can become contaminated from various sources and contaminants can also enter your water when the tap is open. Diarrhoea is not only caused by waterborne pathogens but can enter your household via contaminated food or unsanitary practices.
Some basic tips
Before spending money on any home water treatment device it may be helpful to ask yourself why you need to have such a technology?
If water has a strange taste, colour or smell or you think it might have too much chlorine or suspect it’s causing gastrointestinal problems, first contact your local water services authority (which is most likely your municipality) to obtain information about possible problems with the water supply. Also checking the quality of your in-house plumbing and the sanitation practices in your home.
Check your tap water quality on the internet, at www.dwa.gov.za/bluedrop.
If you really do need a home water treatment device, find out how many litres of water can be treated before maintenance of the device or replacement of parts is required. Ask what the additional costs, maintenance and service on the chosen device are.
Assess and calculate what the costs and timeframes are for maintaining the chosen device.
Be aware of the capabilities and limitations of the technology you choose.
Make sure you know what type of water that needs to be treated. For example, is it municipal water or borehole water, etc. The type of water and the quality problems it is therefore likely to present will have a major impact on the suitability and effectiveness of the chosen water treatment device.
Buyers of home water treatment devices have every right to check if the certification displayed on the product or packaging is authentic. However, they should also understand that certification in itself does not tell them that the device is suited to their needs. Find out what each certification standard entails before making your decision.
The Department of Water Affairs launched the Blue Drop Certification system in 2008, a programme that encourages local municipalities to improve their water quality management while empowering consumers with the right information about what is coming out of their taps. You can check laboratory data on tap water quality in different suburbs on a dedicated “My Water” website: www.dwa.gov.za/bluedrop.
The associated report is entitled “An independent investigation into the purification capacity of small-scale water purification units supplied in South Africa” The reports and consumer pamphlet can be downloaded free of charge from the WRC website: www.wrc.org.za.