SINGAPORE - In the past two months, two home-grown water filtration companies – Sterra and Purexygen – have come under fire for misleading advertisements over the health benefits of filtered water from their systems.

The incidents have prompted a review of the marketing practices of the water filtration industry, the Competition and Consumer Commission of Singapore said on March 21, after it flagged marketing material from Purexygen, which claimed its filtered water can prevent diabetes and other health problems.

The consumer watchdog is also probing Sterra, which in February was flagged by national water agency PUB for an advertisement that claimed that tap water here contains harmful micro-organisms.

Water and nutrition experts told The Straits Times that filters can give consumers peace of mind, but Singapore’s water supply is largely safe to drink without additional filtration systems.

Q: Do I need a sterilising water filter system?

A: Most people here will not need filters as tap water in Singapore has gone through multiple rounds of treatment before it flows into households, said Professor Shane Allen Snyder, a professor of civil and environmental engineering and the executive director of the Nanyang Environment and Water Research Institute at Nanyang Technological University (NTU).

Raw water from reservoirs and other collection points is treated, filtered and disinfected, removing harmful bacteria and particles in the process, according to PUB. Tap water here is well within the World Health Organisation’s guidelines for drinking-water quality and is fit for drinking directly from the tap without any further filtration, it added.

Prof Snyder also pointed out that regulations here forbid the use of lead in pipelines for potable water, a frequent issue with older systems and a common concern overseas.

Chlorine injected into tap water here also helps to neutralise pathogens, he said. “The chances of pathogens making it through water are low. You would know if it does because it would cause entire communities to be ill, and not just individuals.”

Those who choose to buy a filter should look for reputable brands with official certification, he said.

In Singapore, filtration systems will not help much but can give peace of mind to users, such as those living in old buildings or near construction areas, said Professor William Chen, a professor in food science and technology and the director of the Future Ready Food Safety Hub at NTU.

Filters may also appeal to those who are put off by the taste of chlorine in tap water, he added.

“Some groups might still want to use a filtration system, and that is a personal decision,” said Prof Chen, who is also director of NTU’s Food Science and Technology programme.

Q: What if I am looking after a baby?

A: Babies under six months should be given only boiled and cooled tap water, according to advisories by British charity National Childbirth Trust.

The water should then be stored in a bottle that has been sterilised. This can be done by steaming it for several minutes.

Boiling and cooling water is the best option for those who are more susceptible to diseases, like infants and the sick, said Prof Snyder.

“It will for sure kill any microbes and drive off most of the chemicals that might be in the water,” he said.

Q: Can water systems really prevent cancer, or make me smarter?

A: There is a lack of scientific evidence to back such claims, said Prof Chen.

There is no shortage of marketing content about alkaline water systems that reduce toxins, repair cells and provide mental clarity. Alkaline content is typically produced through ionising machines that use a process called electrolysis to raise the alkalinity of water passing through.

Prof Chen said that alkaline content is neutralised once water enters the stomach, which contains acids. “The effect becomes negligible,” he said.

Regarding cancer-causing agents in water, he said that such agents, if any, can be small and thus may not be stopped by a filter. 

Q: When should I be worried about the water I drink?

A: Familiarise yourself with the water standards of a country and whether its tap water is known to be safe for drinking, said Prof Snyder.

“If you have been away for a week or so, it is not a bad idea to run the water for a few minutes to clear out the old water in the tank and get chlorinated, disinfected water back into the pipes,” he said.

Filtration systems do not solve all problems, as users could grow complacent and neglect cleaning the filter and its pipes, which could lead to bacteria growth, said Prof Snyder. As a rule of thumb, stop drinking water from the tap if it tastes strange or does not look clear, he said.

“There are many potential sources of contamination, like the haze in the air or the food we eat, and not just water. For most issues, our bodies have defences to deal with them,” Prof Chen said. “We must adopt a balanced view.”