A new global study suggests that drinking chlorinated water may raise the risk of certain cancers. Researchers found that drinking water with chlorine is linked to a 33% higher risk of bladder cancer and a 15% higher risk of colorectal cancer.
Chlorine in Drinking Water
Chlorine is added to drinking water to kill harmful bacteria and viruses. It has been used for over a century. Chlorine helped stop diseases like cholera and typhoid, which were deadly in the past. This has helped improve public health and life expectancy worldwide.
But scientists have learned that when chlorine mixes with organic matter in water, it creates harmful chemicals. These chemicals are called trihalomethanes (THMs). Some THMs, like chloroform and bromoform, may cause cancer in animals. This raises concerns about the safety of chlorinated water for humans.
What Are THMs?
THMs are present in nearly all public drinking water supplies. These chemicals form when chlorine reacts with plant matter or other organic materials in water. The U.S. Environmental Protection Agency (EPA) sets a limit of 80 parts per billion (ppb) for THMs in drinking water. The European Union has set a limit of 100ppb.
However, the new study suggests that even lower levels of THMs may increase cancer risk. The study found that THM levels as low as 40ppb could be linked to higher cancer risks. Some water systems, like New York City’s, have THM levels around 40ppb. The study also found that the cancer risk may increase as THM levels rise.
The Environmental Working Group (EWG), a public health organization, argues that the safe limit for THMs should be much lower—0.15ppb. This raises the question: are the current THM limits safe enough to protect public health?
Large Study Shows Cancer Link
This study, one of the largest ever done on the topic, reviewed data from 30 studies with 90,000 participants. The study found that men were at a higher risk of bladder and colorectal cancer from chlorinated water. The reason for this is not fully understood.
The study mostly looked at bladder and colorectal cancers. There is still not enough research to show if THMs are linked to other cancers. However, researchers suspect that these chemicals mainly affect the bladder and intestines. This is because the body passes out waste products from the bladder and intestines.
What Does This Mean for Water Authorities?
These findings create a challenge for water authorities. Chlorination has been essential in making drinking water safe for many years. But it is also clear that chlorine byproducts like THMs may pose a cancer risk.
Water sources like rivers and lakes contain more organic material, which can lead to higher THM levels than groundwater. Water treatment plants could try to lower THM levels by using extra filtration before chlorination. However, this is not a simple fix. Reducing chlorine too much could allow dangerous bacteria and viruses to survive in the water, causing new health risks.
Other methods, like ultraviolet (UV) light or advanced filtration systems, could be safer alternatives. These methods can kill harmful microbes without creating THMs. However, they are expensive and difficult to use on a large scale.
How Can You Protect Yourself?
Despite the study’s findings, municipal tap water is still safe to drink. Chlorination has saved many lives by preventing waterborne diseases. But for those who want to reduce their exposure to THMs, there are steps they can take.
Granulated activated carbon (GAC) filters are one of the best ways to remove THMs from drinking water at home. These filters can reduce the amount of THMs in your tap water.
The Need for Better Water Treatment
Chlorine in drinking water has played a key role in improving public health. But the new study shows that there may be hidden dangers, especially when it comes to cancer risk. Policymakers and water authorities need to look at new ways to treat drinking water that do not create harmful byproducts.
While chlorination has saved millions of lives, it may not be enough to protect us from long-term health risks. We need more research and better solutions to ensure clean drinking water without putting our health at risk.
For more health news updates, visit Euro News 24.
