Contaminant explainers
Short guides for contaminants that often appear in Texas utility reports and violation tables. Always verify numbers against your CCR and EPA definitions.
Lead
Lead usually enters drinking water from old pipes, solder, or fixtures—not from the source water itself. Even low levels matter for kids and pregnant people.
Copper
Copper can leach from household plumbing. Short-term high levels can cause stomach upset; long-term high exposure can affect the liver and kidneys.
Arsenic
Arsenic can occur naturally in some groundwater or from industrial/agricultural sources. Texas has regions where groundwater arsenic is a known concern.
Nitrate
Nitrate often comes from fertilizer, septic systems, or animal waste. It is a special concern for infants.
Total trihalomethanes (TTHMs)
TTHMs form when chlorine disinfectant reacts with organic matter in the water. They are more common in surface-water systems.
Haloacetic acids (HAA5)
HAA5 are another group of disinfection byproducts formed when chlorine reacts with organic matter.
Total coliform / E. coli
Coliform bacteria are indicators. Their presence can signal a pathway for disease-causing microbes. E. coli in drinking water is an acute health concern.
Radium-226/-228
Radium is a naturally occurring radioactive metal that can dissolve into groundwater in some geologic formations.
Fluoride
Fluoride occurs naturally and is sometimes added for dental health. Too much can cause dental or skeletal fluorosis.
PFAS (per- and polyfluoroalkyl substances)
PFAS are persistent “forever chemicals” used in many industrial and consumer products. EPA has begun regulating specific PFAS in drinking water.