Swimmers beware: a dip in the sea can make you seriously ill

Bathing in the sea – including off British beaches – causes more disease worldwide than scourges such as leprosy and diphtheria, according to a United Nations report.

Even taking a splash in waters that pass EU and US pollution standards can be dangerous.

One in every 20 people who bathe in them, it says, will become ill after just one dip.

The report, drawn up by representatives of eight UN agencies – including the United Nations Environment Programme, the World Health Organisation, and the International Maritime Organisation – contradicts repeated government assurances that swimming in officially approved waters is safe.

It adds: "Contamination of the sea has precipitated a health crisis of global proportions."

The contamination, by sewage, can cause serious illnesses such as meningitis and hepatitis A, both in Britain and abroad.

But by far the greatest number of cases are relatively minor stomach and ear, nose and throat ailments.

These, however, reach massive proportions. The report – entitled A Sea of Troubles – estimates that bathing in water contaminated by sewage causes "some 250 million cases of gastroenteritis and upper respiratory disease every year".

It adds: "Some of these people will be disabled over the longer term."

The report calculates the impact of illness by totting up the total years of healthy life lost through disease, disability and death using the Disability Adjusted Life Year (Daly) measurement, which has been developed by the World Health Organisation and the World Bank.

This shows that the world-wide burden of disease contracted through bathing amounts to up to 800,000 Dalys, far outdistancing leprosy (380,000 Dalys) and diphtheria (360,000 Dalys).

And it costs the world up to £1.56bn a year.

Scientists say that the equivalent figures for Britain have yet to be worked out.

But Professor Gareth Rees of Askham Bryan College near York – long one of the country's foremost experts in the field – says: "There is an enormous and hidden burden of disease from bathing in Britain which the Government has played down."

Britain's beaches have been getting cleaner over the past decade. Ten years ago more than one in every five failed the EU standards: now 19 out of every 20 pass. In all, 23 beaches around the country failed last year (see map).

Even so, we still have the second highest proportion of failures in the EU, after Finland. The official European Commission figures suggest that, if you want clean water, you are much better off in Spain (98.2 per cent passing), Portugal (98.4 per cent) or Greece (99.4 per cent).

But this only tells part of the story.

The World Health Organisation believes that the standards need to be at least 20 times stricter for healthy bathing.

Just over 40 per cent of the country's beaches fail the WHO standards.

They include such popular resorts as Blackpool, Morecambe, Weston-super-Mare, Brighton, Eastbourne, Herne Bay, Southend, Filey and Bridlington.