BOTTLED water may be responsible for thousands of cases of food poisoning every year. A study by public health specialists at the University of Wales found that contaminated water could account for more than one in ten infections involving campylobacter, the biggest cause of food-borne sickness in the Western world.

Scientists from the public health laboratories in Cardiff investigated more than 200 cases to see what might have caused it. They gathered details of what the victims had eaten and drunk, where they had travelled, and whether they had been in contact with farm animals, a known risk. They compared the data with a control group that did not have food poisoning, to identify what it was that increased the chances of sickness.

The results, published in the journal Emerging Infectious Diseases, showed up to 12 per cent of cases could be attributed to bottled water, over 30 per cent to contaminated chicken and 21 per cent to raw salad foods such as tomatoes and cucumbers. “The increased illness from contamination of bottled water could be considerable,” said Meirion Evans, from the department of epidemiology at the University of Wales in Cardiff. “Drinking bottled water has not previously been recognised as a risk factor. But it is biologically plausible and could explain a substantial number of infections.” Campylobacter now infects about 50,000 people a year in England and Wales, yet until the mid-1970s only a couple of thousand cases a year were identified.

Over the same period the consumption of bottled water has substantially increased. Today Britons drink 1.4 billion litres (300million gallons) of bottled water every year. Campylobacter causes stomach pains, diarrhoea and weakness in most people. Mild cases can be treated by avoiding food and drinking lots of fluids.

One in a thousand sufferers developed a devastating condition called Guillain-Barré syndrome, which can lead to total paralysis. Dr Evans said: “A variety of organisms can be found in mineral water and will survive for a considerable length of time, particularly in uncarbonated water supplied in plastic bottles or bottled by hand. “To our knowledge, campylobacter has not been identified in mineral water but this may simply be because testing is rarely undertaken.” Iain Ogden, from the medical microbiology department at Aberdeen University, said it was possible for campylobacter to slip through the testing net. “It’s a small organism and routine filtration does not remove it. “But the chances of someone who drinks bottled water consuming an infective dose, the amount needed to trigger infection, are probably quite small.” A spokesman for the Natural Mineral Water Service insisted that manufacturers did test for campylobacter. Researchers had failed to differentiate between mineral water that had come from a protected underground source and other types of spring water, she said. She said: “Natural mineral water has to come from a clean, unpolluted source.” Richard Laming from the British Soft Drinks Association, which represents mineral water manufacturers, also insisted there was no good evidence that water was causing food poisoning. Producers were compelled under the Food Safety Act to test for the presence of organisms and withhold any contaminated water from sale, he said.

Back to Media & PR