Bracing morning showers and soothing bedtime soaks were blamed late Wednesday for increased water pollution due to medicated soaps and shampoos.

In a study unveiled at a National Meeting of the American Chemical Society in San Francisco, scientists said they have zeroed in on a major source of the active pharmaceutical ingredients (APIs) that are an ever-worsening environmental concern.

"We've long assumed that the active ingredients from medications enter the environment primarily as a result of their excretion via urine and feces," said Dr. Ilene Ruhoy.

"However, for the first time, we have identified potential alternative routes for the entry into the environment by way of bathing, showering, and laundering."

Ruhoy said lotions, creams, gels and skin patches are to blame for a significant amount of the APIs in ground water.

She encouraged consumers to use their medicated products sparingly and doctors to prescribe lower-dosage levels to cut down APIs.

"We need to be more aware of how our use of pharmaceuticals can have unwanted environmental effects," Ruhoy said. "Identifying the major pathways in which APIs enter the environment is an important step toward the goal of minimizing their environmental impact."