Whole Effluent Toxicity Laboratories

Whole Effluent Toxicity Laboratories

Discharges to receiving waters in the United States are regulated through the National Pollutant Discharge Elimination System (NPDES) or state equivalent. Under the NPDES program, Whole Effluent Toxicity (WET) tests are used to measure compliance with toxicological limits in permits. With experience in a vast array of U.S. EPA standardized test protocols, TRE assists its private and public sector clients in meeting their regulatory obligations. While the actual number and type of studies conducted by TRE is broad, more common toxicity tests include:

  • Acute and short-term chronic tests with the fathead minnow, Pimephales promelas, and freshwater cladoceran, Ceriodaphnia dubia
  • Acute tests with freshwater cladocerans Daphnia magna and D. pulex
  • Short-term chronic tests with D. magna
  • Cell growth studies with the green alga, Pseudokirchneriella subcapitata (formerly Selenastrum capricornutum)
  • Acute and chronic tests with the marine fish Menidia beryllina, Atherinops affinis and Cyprinodon variegatus
  • Acute and chronic tests with the mysid shrimp, Americamysis bahia

TRE cultures many of the organisms it uses, a factor that allows TRE researchers to more precisely control the age and quality of organisms used in WET and other tests. Although the vast majority of our clients routinely pass their WET permit limits, some effluents may occasionally demonstrate toxicity. In those cases, TRE can assist clients by conducting a Toxicity Identification Evaluation (TIE) to determine the exact cause(s) of observed toxicity, and further provide direction and support of a Toxicity Reduction Evaluation (TRE), leading to effective toxicity reduction solutions. Our lab is located in Fort Collins Colorado.