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Column originally published Jul 12, 2000
Column last revised/updated on Oct 23, 2018

Safety Of Drinking Water Should Be A High Priority

Question: The E. coli outbreak in Walkerton Ontario makes us very nervous. We live in a rural area surrounded by cattle farms. Our well is the only source of drinking water for the entire family. What should we do now? Should we get someone to check our well, and how often should we do this? Or should we just go ahead and buy bottled water? How can we know that it is safe? Please help us because we are really worried.

Answer:

The outbreak at Walkerton Ontario is truly a wake-up call for all of us. We Canadians live in a country with the best source of water. The Americans are trying to pipe our water south. Unfortunately we have allowed our water to become contaminated and cause an outbreak of this magnitude.

One thing for sure is that Walkerton is not the first and only place where people get sick from the drinking water. Every year, probably thousands of people develop diarrhoea from their drinking water. E. coli O157:H7 is only one type of bacteria, there are many other bacteria and parasites that can contaminate our water. What makes Walkerton unique is contamination of the whole municipal water supply. For those readers who are not as familiar with this outbreak, let me briefly outline what had happened.

In May of this year, two patients with severe bloody diarrhoea were admitted to Walkerton Hospital. Their diarrhoea was found to be caused by E. coli O157:H7. They were subsequently transferred to Owen Sound Hospital because of their illness. Shortly after, the Public Health Laboratory reported the same bacteria being found in the town’s municipal water supply. A “boil water advisory” was issued for all the residents of this small town.

In total, seven deaths were directly linked to the outbreak, including one child. There were other deaths that are still being investigated. Altogether, over 600 were infected in this small town of 5,000 people.

There is no surprise, in a way, that this outbreak could have occurred. E. coli O157:H7 has been associated with cattle, growing in the intestines of these animals, and excreted in the feces. With the increase of “factory farming” in many Ontario farms, large numbers of cattle are concentrated in relatively small areas. Their excrement has been associated with a number of health problems, gastrointestinal infection is just one of them.

In Alberta, where factory farming is very common, gastrointestinal infections including this strain of E. coli have become much more prevalent than before this practice of farming. This does not mean that the problem does not occur in the rest of the country. Severe E. coli O157:H7 infections have occurred in Prince Edward Island also.

I should clarify that E. coli O157:H7 is only one of the strains of E. coli. The designation “O157:H7” identifies this strain by the characteristics on the cell wall. This particular strain was first implicated in human illness almost twenty years ago. Most of the outbreaks occurred after eating contaminated food. The most common one is hamburger: that is why it is also called hamburger disease. The beef is contaminated with bacteria from the animals’ intestines in the slaughterhouse. In grinding the meat into hamburger patties, bacteria were mixed inside. If the hamburgers are not cooked well, these bacteria can survive and start an infection.

After entering the intestines, the bacteria multiply and produce poisons called Vero or Shiga toxins. The most common symptoms include fever, abdominal cramps, and bloody diarrhoea. A small number of infected individuals, especially those very young and very old, or anyone with a weakened immune system, can develop a serious complication called haemolytic uremic syndrome. This condition leads to breaking down of red blood cells and kidney failure. Unless the condition is recognized early and treated promptly, death can occur within days.

The exact reason for the outbreak in Walkerton is yet to be determined by an independent inquiry. It is safe to say that we have to work harder to safeguard our water supply. For those who depend on municipal water, we should make sure that the local and provincial governments are doing everything to ensure the water supply is safe.

We should also be concerned about the spread of these “factory farms” across the country. These farms operate by raising a large number of cattle or pigs on a small plot of land. The amount of waste produced by these animals is often many times greater than human. Presently there are no regulations for these farms to set up waste treatment plants to detoxify and decontaminate the waste. Walkerton is located in the middle of these “factory farms.”

Of course there are other sources for E. coli infection. Other foods, including sausages, apple juice, milk, and cheese, have been linked to small and large epidemics.

In the last ten years, many outbreaks in North America have been traced to recreational water activities, including swimming pools, water parks, fountains, hot tubs, lakes and rivers. As expected, most of these happen during the summer months.

Since you live in a rural area surrounded by cattle farms, you do face the risk of your water supply becoming contaminated. The risk probably is greatest after heavy rainfall, when there is large runoff of water into the wells. The best way is to have your water tested for possible contamination. Depending on where you live, your local government may already have a laboratory set up for these tests.

Presently, there is no definitive recommendation how often these wells should be tested. If you want to be safe, have the water tested a couple of times a year. Another good practice is to boil your water before drinking. This should kill any bacteria that may have contaminated your well. This practice, however, does not remove any chemical in your water.

Is bottled water really better? The water is usually taken from a spring or from municipal water. All the companies that market bottled water have additional processes to filter the water and kill potentially harmful bacteria. There are strict guidelines that these manufacturers have to follow.

If you ask, is there any chance that bottled water may not be safe? Of course it is possible. But with the additional processes involved, it does increase the safety margin of the bottled water.

I hope I have provided you with some useful suggestions here. Be proactive: make sure your water is safe to drink!

[Note to Readers: This column was written shortly after the Walkerton crisis. We all know that the inquiry showed that there were mistakes made in testing and protecting the municipal water there. Bottled water has its issues, including plastic waste as well as microscopic particles of plastic found in the water itself. There is a strong push for using reusable water-bottles instead of bottled water. Each of us have to make our own choice, pay attention to scientific findings, and try to protect our precious environment.]