Many public water supplies are chlorinated to help ward off dangerous bacteria that can become a public health concern when present. Without chlorination we could have serious outbreaks of disease caused by bacteria, viruses and parasites, which are still very common in under-developed countries around the world.
Disinfection by-products (DBPs); trihalomethanes (THMs) and haloacetic acids (HAAs), are formed when chlorine is added to water that contains organic materials such as algae, weeds, and decaying leaves. The residual chlorine reacts with the organic material and forms a group of chlorinated chemical compounds.
The most common ways that exposure occurs are drinking water containing DBPs, breathing in DBPs from showering, washing dishes or boiling water, and absorption through the skin from bathing, showering or frequently swimming in pools/hot tubs.
The health risks associated from DBP’s are typically from long-term exposure. High level exposure over many years can cause bladder cancer, and create issues with liver, kidneys and circulatory system. There is also a correlation between DBPs and pregnancy and miscarriages, premature births, low birth weight and birth defects.
There are guidelines set forth by the EPA that public water supplies must follow in order to limit exposure of DBPs. Regular required testing helps to ensure public health. Though there are risks with long-term exposure to DBP’s in drinking water, the greater risks lies with not killing the disease laden bacteria that can wreak havoc on our society.
