Researchers from The Meadows Center for Water and the Environment at Texas State University, Texas Woman’s University and the University of North Texas have developed a low-cost community science method to help identify potential human wastewater contamination in rivers and streams.

The method, known as “tampling,” uses absorbent cotton to detect optical brighteners — fluorescent compounds commonly found in laundry detergents, cleaning products, textiles and paper products. Their presence in surface water can indicate potential human wastewater contamination.

Researchers tested the approach at nine sites along Cypress Creek in Hays County, Texas, deploying more than 100 samples to evaluate sampling times, contamination risks and inexpensive field equipment. The work helped Texas Stream Team develop standardized procedures, quality controls and training materials for incorporating optical brightener monitoring into its certified statewide program.

The method was added to Texas Stream Team’s Quality Assurance Project Plan following review by the Texas Commission on Environmental Quality. The program began offering optical brightener community scientist training in 2025.

Researchers emphasize that tampling does not replace laboratory or professional water quality testing because it only identifies whether fluorescence is present and does not quantify contamination levels. Instead, the screening method can help communities identify areas that may warrant additional testing or investigation, potentially allowing monitoring resources to be focused on higher-priority locations.