"Apart from being ripped off, consumers are also threatening their health and the environment," the NCF said.
In the United States, public pressure has been growing to force powerful corporations to disclose where their bottled water comes from, after research indicated that up to 40% of bottled water uses tap water as its source.
Even one of the US's leading brands of bottled water was found to contain tap water.
In the US, some consumers are already paying a 3 000% premium on water by buying it in bottles instead drinking it from their taps, the NCF said.
SA consumers should be careful
"Were this to be the case in South Africa, consumers would be paying a thousand times more for the water in a 500 ml bottle than they do from their taps."
The NCF urged SA consumers to be cautious when buying bottled water, and to check whether the label indicated clearly where the water had been sourced.
"We suspect that there is a similar trend in our own country to what is happening in the US," said NCF Chairman Thami Bolani.
"Business sees an opportunity for a quick buck, and there are dozens of companies jumping on the bandwagon. Being as fashion-conscious and status loving as we are, SA consumers have easily taken to buying bottled water - even though we have no need to."
Bolani said if the US had a problem in controlling the honesty of suppliers, then SA should be extra vigilant.
Impacts on the environment
He also urged government's consumer protection agencies to be vigilant about the possible abuse of consumer rights when it came to bottled water. He said standards need to be applied and enforced in this industry.
In terms of its impact on the environment, bottled water leaves a huge carbon footprint, according to research carried out in the US.
Making bottles to meet Americans' demand for bottled water required more than 17 million barrels of oil a year - enough fuel for more than a million US cars for a year - and generated more than 2.5 million tons of carbon dioxide.
There was also a negative impact on communities around the world, and their immediate environment as bottlers extracted water in huge amounts from local springs, potentially drying them up.
They also depleted wetlands and drained rivers, with serious impacts on ecosystems. – (Sapa)