Seven years after Canada's worst tainted water disaster hit Walkerton, residents of the Ontario town are still suffering health problems from E. coli contamination, according to a study.

In fact, the incidence of irritable bowel syndrome — which can cause abdominal pain and bouts of diarrhea or constipation — among residents in the study is twice the normal rate, says the study released Friday.

E. coli can lead to hemolytic uremic syndrome, a condition that can cause acute kidney failure in children.
(CBC)

Seven people died and more than 2,300 became ill in the spring of 2000 after the town's water supply became contaminated with E. coli bacteria.

After a public inquiry in 2003, town water plant manager Stan Koebel and Frank Koebel, ex-foreman of the town's public utilities commission, were charged with public endangerment, fraud and break of public duty. After the two pleaded guilty to common nuisance, Stan Koebel was sentenced to a year in jail and Frank Koebel received nine months house arrest.

The ongoing Walkerton Health Study, started in 2000, involves 4,500 residents.

The findings released Friday say the 19 children who recovered from hemolytic uremic syndrome, a condition that can be caused by exposure to E.coli and can lead to acute kidney failure, still have after-effects. Testing has indicated they still have excess protein in their urine and slight reductions in kidney function.

Researchers also note that last year, there was an increased incidence of self-reported arthritis among area residents. Of those people who suffered moderate symptoms of E. coli poisoning in 2000, 17.6 per cent reported new arthritis symptoms. As well, 1.6 per cent of residents who experienced severe effects reported arthritis symptoms.

"Our primary goal continues to be assisting residents of Walkerton and surrounding area in pursuing lifestyles that promote health," Dr. Bill Clark, chair of the operations and research committee of the health Study, said in a release.

"Continued participation ensures our ability to learn more about the long-term effects of the water contamination of May 2000."

Researchers will continue to monitor residents and introduce a new test to accurately assess kidney function. They plan to issue a health report card for the town next year.

The study is led by researchers and doctors from the Lawson Health Research Institute at the London Health Sciences Centre, and the Schulich School of Medicine and Dentistry at the University of Western Ontario, as well as McMaster University in Hamilton.

With files from the Canadian Press