TCEQ Class C Surface Water License Practice Exam

Chlorination is a commonly used method for disinfecting drinking water and controlling microbial pathogens. However, the process of chlorination can also lead to the formation of disinfection byproducts (DBPs), which are chemical compounds that result from the reaction of chlorine with organic matter present in the water.

The correct answer highlights the dual nature of DBP formation during chlorination. Some DBPs can be harmful to human health, such as trihalomethanes (THMs) and haloacetic acids (HAAs), which have been associated with potential cancer risks and other health concerns. On the other hand, some DBPs may be relatively harmless or less toxic, although ongoing research continues to assess the health implications of various byproducts.

This context demonstrates that while chlorination is effective for disinfection, it does not prevent the formation of DBPs entirely; in fact, it can result in a complex array of both harmful and harmless compounds, depending on factors like the type of organic materials in the water and the conditions of chlorination. This understanding is crucial for water treatment operators as they balance the need for pathogen control with managing the health risks associated with DBPs.