What do TTHMs stand for?

TTHMs stand for Total Trihalomethanes. This term refers to a group of four chemical compounds formed when chlorine or other disinfectants used in water treatment react with natural organic matter like decaying vegetation in water. The compounds include chloroform, bromodichloromethane, dibromochloromethane, and bromoform.

Understanding TTHMs is significant because they are monitored due to their potential health effects when present in drinking water at elevated levels. They are considered a class of disinfection by-products and are regulated under the Safe Drinking Water Act. Recognizing the complete term, "Total Trihalomethanes," is crucial for proper communication in water quality contexts, especially when discussing water safety, testing results, and regulatory compliance.

The other options, while they may use similar terminology, do not accurately represent what TTHMs stand for in the context of water treatment and analysis.