The E. coli ordeal of contaminated drinking water in Walkerton, Ont., will live on in many people with reduced kidney function and an increased risk of hyertension, a leading medical journal reported on Friday.

Experts had expected the study's results, but it's the first time that a peer-reviewed journal had investigated the tragedy four years ago.

Acute gastroenteritis sickened 2,300 people and killed six in the small rural community 130 km west of Toronto, according to the Canadian Medical Association Journal.

"Acute bacterial gastroenteritis necessitating medical attention was associated with an increased risk of hypertension and reduced kidney function four years after infection," wrote lead researcher Dr. William Clark.

However, co-author Dr. Amit Garg said the study does not make conclusive links between exposure to E. coli and numerous other health-related problems in the people who became ill after drinking the water.

The study involved 1,958 adults with no known history of hypertension or kidney disease before the outbreak. It found that 27 per cent of those who didn't get sick and 32.3 per cent and 35.9 per cent respectively of those who had moderate and severe symptoms were diagnosed with hypertension.

The study found 38, or 4.3 per cent, of participants had reduced kidney function, but none had end-stage kidney failure.

  • INDEPTH: Death on tap: The poisoning of Walkerton

    The town's water supply was inadequately chlorinated after heavy rains washed livestock manure into a shallow well.

    It was North America's most serious case of water contamination in recent history and garnered widespread media attention.

    An investigation found that two brothers who had been in charge of safeguarding the town's water supply knew it was impure, but failed to rectify its quality and fudged records.

    Many awaiting compensation

    One hundred and sixty-nine Walkerton residents, many of whom have complex health conditions, are still waiting to resolve claims for provincial compensation.

    Kim Chalmers, manager of the Walkerton Compensation Plan, said it will take more time to sort out which of the more complicated cases were caused or aggravated by exposure to the tainted water.

    However, she noted that there is no deadline for claims to be filed or settled.

    So far, the provincial fund has paid out $55 million to the victims of the water contamination.