Disinfection Byproducts in Drinking Water: THMs & HAAs Explained

When chlorine reacts with organic matter, it forms disinfection byproducts (DBPs).

Common DBPs

• Trihalomethanes (THMs)
• Haloacetic acids (HAAs)

Why They Matter

Long-term exposure to elevated DBPs has been linked in studies to potential health concerns. Levels often rise:

• In warmer months
• In older systems
• Where source water quality fluctuates

This is especially relevant for Midwest surface-water systems.

Next: How to Reduce Chlorine in Drinking Water at Home