Water Distribution Grade 1 Certification Practice Exam

What are trihalomethanes?

1. A family of organic compounds derived from nitrogen

2. Derivatives of methane with halogen atoms

3. An indication of water salinity

4. Organic pollutants primarily originating from agricultural runoff

The correct answer is: Derivatives of methane with halogen atoms

Trihalomethanes are derivatives of methane that contain three halogen atoms, which can include chlorine, bromine, or fluorine, among others. These compounds are typically formed when chlorine, a common disinfectant used in municipal water treatment processes, reacts with organic matter that is naturally present in water sources. The presence of trihalomethanes in drinking water is a significant concern because some of these compounds, such as chloroform, are known to have potential health effects, including being carcinogenic. Understanding their nature as derivatives of methane is crucial for water quality management, as it enables water treatment professionals to identify sources of contamination and implement appropriate measures to minimize their formation. The other options do not accurately describe trihalomethanes. They highlight different categories of compounds or issues not related to the chemical nature of trihalomethanes. By focusing on the correct identification of these compounds, it becomes easier to address the regulations and health implications associated with their presence in drinking water.