Gross Alpha Particle Activity measures radioactivity from alpha-emitting elements in water. It's often linked to uranium and radium in groundwater, increasing cancer risk.

Gross Alpha Particle Activity occurs naturally in rocks and soil, entering groundwater through erosion. Measured in picocuries per liter (pCi/L), it serves as a screening tool for radioactive contamination in water supplies. While not specific to any single element, it often indicates the presence of uranium or radium. The EPA regulates acceptable levels in drinking water to minimize potential health risks associated with long-term exposure to alpha radiation.