A new straw that purifies water as it is drunk is hoped to be part of a solution to water-borne disease killing thousands in developing countries.
The LifeStraw is used in some places direct from the river
Water from most sources can be drunk if done so through the LifeStraw say the makers of the product.
Created by Danish innovator Torben Vestergaard Frandsen the straw is made of plastic and resembles a flute. Inside are filters and a chamber impregnated with iodine. These remove the bacteria from the water as it is drunk.
"You basically just suck the water through it," said Alan Mortensen, business director of the Public Health Water-Bourne Disease Control - which produces the LifeStraw - told BBC World Service's Culture Shock programme.
"You just need to suck a few times to get the water through all the filters."
The company that makes the LifeStraw, Vestergaard Frandsen, emphasise that it hopes the invention can help to meet the UN's Millennium Development Goals on providing access to clean drinking water.
In the developing world, one person in six does not have access to drinking water, and 6,000 people a day die from water-borne diseases.
The LifeStraw, however, is designed to filter these out - it includes a disinfectant filter which kills bacteria, and active carbon which removes parasites and gives the water a better taste.
Mr Mortensen said that using the straw, it would be possible even to drink water from the notoriously polluted Thames river in London.
"You'd definitely have a bacteria-free drink," he said.
"You might still taste some of the algae, but you could do it, no problem."
He added that as the straw is aimed at the developing world, it is being made it in China, where production costs are lower.
It is priced at around $3.50 (£1.85) a straw. Each one will last for around 700 litres, around six months to a year.
However, a spokesman for UK charity WaterAid, which works to supply clean water and sanitation in 17 of the world's poorest countries, condemned the device as overly expensive, and said it was not a real solution.
The organisation's Paul Hetherington said that while he thought the LifeStraw is an 'amazing-sounding idea,' he did not ultimately think it would help.
"$3.50 sounds like very little to you and me - but most people in those countries earn less than one dollar a day, with which they have to feed their families," he said.
E.coli is amongst the diseases the LifeStraw filters out
He added that he felt the problem is that many people live very far away from their water, often walking a total of 20km or more carrying a weight of 25 kilos.
"That's what takes it out of them - the long journey," he explained.
"The LifeStraw isn't going to prevent that long journey, even if it does improve the water they drink.
"They're not going to have the education, because they're not going to have the time. It's girls in particular who suffer, because it's women and girls who have to collect the water.
"It only costs a charity like WaterAid £15 per person to provide them with water, sanitation and hygiene education, which, provided there is decent water resource management in the country, will last them a lifetime.
"At that rate, $3.50 is expensive."