Danish inventor Torben Vestergaard Frandsen created a straw with filters and an iodine-impregnated chamber to remove bacteria from water as it is drunk.
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."
"Contrary to popular belief, water quality in the Thames is a lot better today than it has been for many years...
...a dramatic improvement in water quality. As a result, many different animals, birds and fish have returned to live and breed in the estuary. Today there are 121 different species of fish and over 170,000 birds in the estuary."
"Contrary to popular belief, water quality in the Thames is a lot better today than it has been for many years...
...a dramatic improvement in water quality. As a result, many different animals, birds and fish have returned to live and breed in the estuary. Today there are 121 different species of fish and over 170,000 birds in the estuary."