Water & healthCan drinking water be delivered without disinfectants like chlorine and still be safe?
When we open the tap, we expect the water to be safe. That is, the water should be free of pathogens that could make us sick and any chemicals that could cause problems later in life. For the most part, potable water systems in the developed world have done a great job providing safe water. However, there are still unfortunate situations that develop, resulting in issues with the safety of drinking water. One of the conclusions of the research we have conducted is that potable water systems should consider moving beyond carrying a disinfectant and focus instead on maintaining and replacing their aging delivery systems and upgrading their water treatment steps. This will have the benefit of limiting exposure to DBP while also continuing to deliver safe water to consumers.
When we open the tap, we expect the water to be safe. That is, the water should be free of pathogens that could make us sick and any chemicals that could cause problems later in life.
For the most part, potable water systems in the developed world have done a great job providing safe water. However, there are still unfortunate situations that develop, resulting in issues with the safety of drinking water.
Most notably, in the past several months, the city of Flint, Michigan, has been dealing with a crisis regarding their delivery of potable water. A significant number of the citizens of Flint were exposed to dangerously high concentrations of lead in their drinking water. The episode was triggered by a switch in drinking water source undertaken by the city, without the proper evaluation of the consequences regarding the change in the chemistry of the water.
The episode has brought much attention to water treatment methods to ensure public safety. In many countries the use of a disinfectant, such as chlorine or chloramine, in the distribution system is required. These countries include the United States and the United Kingdom. A disinfectant is used as a final barrier to protect human health against potential contamination events during distribution.
However, there are a number of countries that do not carry a disinfectant that remains in the water once it’s distributed. How can these countries deliver safe water without this disinfectant included?
In a recently published paper, we, together with other colleagues, set out to evaluate this question. Our main motivation was to take a close look at whether municipalities could avoid some of the potential negative effects of a disinfectant while still ensuring public health.
The pros and cons of disinfection
One of the great public health successes of the 20th century was the eradication of most waterborne epidemics in the developed world. In the year 1902, chlorine was first added to water as a disinfectant in Belgium. Additional sites in the United States and the United Kingdom following suit by 1908. This resulted in a decrease in the incidence of waterborne diseases.
Fast forward to 1974, when Dutch researchers discovered the presence of chloroform, a probable human carcinogen, in potable water.
