Clear water revival

UK-developed drinking bottle uses nanotechnology to purify disease-ridden water. Jon Excell reports

Clean drinking water. As well as being essential to survival, it is also heavy, difficult to transport and in many parts of the world could soon become a rarer commodity than diamonds or gold.

Now a water bottle that is claimed to instantly render the most foul, disease- ridden water drinkable could be set to revolutionise the world of emergency aid.

Invented by UK entrepreneur Michael Pritchard, the Lifesaver bottle uses an innovative nanoscale filtration membrane to remove bacteria, viruses, and all other water-borne pathogens from water instantly.

Inspired to invent the bottle after seeing the problems caused by the lack of safe drinking water in the aftermath of the 2004 tsunami, Pritchard explained that it works on the principle of pore size. ‘The pores are 15nm and the smallest virus is 25nm. There’s nothing smaller than a virus — it pretty much stops everything,’ he said. These bold claims were recently backed up by independent tests carried out by the London School of Hygiene and Tropical Medicine.

The filter is essentially a miniaturised version of the kind of hollow-fibre ultrafiltration system that has been used by the water processing industry for a number of years. The trick with the Lifesaver bottle, said Pritchard, was taking this technology and finding a way of shrinking it down into a 12in plastic bottle.

Two filter cartridges are available, designed to filter either 4,000 or 6,000 litres of water over their lifetime. As it approaches the end of its life, the cartridge requires a greater number of pumps to make water flow and ultimately the flow will stop entirely.

The membrane is protected from grit and gravel by a pre-filter disc situated in the base of the bottle. This can also be used as a sponge to soak up water from hard-to-reach areas such as cracks in rocks or shallow puddles. The bottle also comes with an activated carbon filter which reduces a broad spectrum of chemical residues, including pesticides and heavy metals such as lead and copper.

To operate the bottle, the user unscrews the base, fills the bottle with water, unlocks the pump handle at the base and builds up pressure inside the filter with a few quick pumps. Opening the teat at the top of the bottle then causes a pressure differential that starts the flow of water across the surface of the membrane.

This means that sterile water is only produced when it is required, and that the water is stored in its contaminated state. This differs to conventional approaches to water purification where water is first purified and then stored in a separate container.

The problem with this method, said Pritchard, is that the vessel used to store filtered water can itself become contaminated very quickly. To illustrate the nature of the problem of water storage, Pritchard cited a 2005 survey carried out by aid organisation Care International indicating that almost 50 per cent of the water stored by people living in Indonesia’s Aceh province was contaminated with E. coli.

Pritchard believes that by removing this problem his device should prompt a rethink over the way aid agencies respond to the challenge of providing clean drinking water to stricken areas. But it also has other advantages over existing approaches to emergency response.

The traditional way of shipping water is, he said, extremely costly. ‘A C17 transport plane can hold 72,000 litres of water. This is enough for three litres a day for a month for 800 people at a cost of £3 per person, per day. You could put 125,000 Lifesaver bottles on the same plane, which would be enough for half a million people for 16 months at a cost of 9p per person per day.’

He added that the bottles could also be delivered far more quickly. ‘Often the problem is that you can’t get water to people because roads are flooded and bridges are gone. But within 24 hours you can airlift these things and drop them in.’

And by removing the enormous problem of water distribution, emergency resources can then be deployed more effectively elsewhere. ‘If people can fend for themselves, then the resources that you would normally use in the first days and weeks for shipping water can be re-allocated to delivering food and blankets and repairing roads — all of the infrastructure stuff,’ said Pritchard.

But despite its obvious potential, the bottle has not yet been embraced by the aid market. And although he is discussing possible trials with a number of organisations, including the Red Cross, Pritchard is frustrated that aid agencies seem hung up on the concept of shipping water.

Somewhat more promising, however, is the area of emergency preparedeness. Pritchard claimed that a number of Middle East governments are interested in storing large numbers of lifesaver bottles in the Dubai humanitarian zone, which would then be sent out, in the event of an emergency, with the message ‘a gift from the people of…’. Intriguingly, Pritchard said that Mormons, who are obsessed with disaster preparedeness, are extremely interested in the product.

Away from the world of disaster relief, the bottle has also attracted the attention of the MoD, which is now subjecting it to a series of laboratory tests ahead of field trials. Pritchard said these are likely to be in Afghanistan or Iraq where a number of the bottles, independently purchased by individual soldiers, are already in use. As well as being used to provide clean drinking water, the military is also said to be interested in the fact that the bottle can be used to direct pressurised jets of sterilised water on to wounds.

The device also has great potential in the highly lucrative outdoor leisure market. Hikers and campers can top up at mountain streams, travellers abroad can drink developing world tap water safely, and canal boat owners can simply reach overboard whenever they fancy a drink.

This, said Pritchard, is now one of the most promising markets. His company, Lifesaver Solutions, has sold thousands of the bottles through its website (it costs £195 for the 4,000 litre version, and £230 for the 6,000 litre size). And following discussions with Blacks and a number of other outdoor specialists, he said the bottle should be available in camping stores within the next few months.