Biomonitor specializes in performing whole effluent toxicity testing for wastewater treatment plants and other point-source elimination systems. The state of Indiana and the Environmental Protection Agency require all point-source elimination meet specific standards of toxicity before the effluent can be safely discharged into a stream, river, or other water body. The results from toxicity testing provide data to determine if a discharger is in compliance and also helps regulators make decisions on permit requirements.

WET Testing

When performing a toxicity test, Biomonitor commonly uses the water flea (Ceriodaphnia dubia) and the fathead minnow (Pimephales promelas). Sometimes the giant water flea (Daphnia magna) or the green algae species (Raphidocelis subcapitata formerly Selenastrum capricornutum) is also used. Other test species are available upon request.

The treated wastewater (or effluent) is collected as a composite sample at the plant. A blank chain of custody used for sample collection can be found here. A series of dilutions are made with the effluent and test animals are introduced to the sample water. For chronic testing factors such as survival and growth (minnows) and survival and reproduction (water fleas) are measured over a seven day period. These animals are known to be sensitive to many contaminants in the water and are bred and reared in the laboratory. Any negative effects of the effluent can be seen through reduced survival, growth, and reproductive rates.