Toxicity Identification Evaluations and Research Studies

Toxicity Identification Evaluations (TIE)

  • Determined surfactants as the cause of effluent toxicity to Pimephales at a textile manufacturing plant.
  • Identified polar organic compounds (amines) as the source of pass-through toxicity from a municipal wastewater treatment facility.
  • Identified Zn from potable water as the source of toxicity from cooling towers at an industrial treatment facility.
  • Identified Ni as the primary toxicant and Cu as a secondary toxicant in storm water runoff from a cobalt mine.
  • Provided evidence that variability in Pimephales chronic tests of several Nuclear and Fossil Power Plant discharges was due to naturally occurring pathogens.  Provided sufficient evidence to have laboratory treatment prior to initiating Pimephales chronic tests implemented in their NPDES permits.

Refractory toxicity assessments and Bench-scale Treatability Studies

  • Performed numerous refractory toxicity assessments (RTA) to determine the potential pass through toxicity that would result from discharge contributions to wastewater treatment plants.


Refractory toxicity assessment to determine pass-through toxicity of a new industrial discharger to a wastewater treatment plant.

North Carolina Action Level Policy

  • Toxicity identification evaluations performed to provide sufficient evidence to North Carolina Department of Environment and Natural Resources (NC DENR) that Cu and Zn were not the cause of whole effluent toxicity permit violations at several facilities.  As a result, Cu and Zn limits were not added to their NPDES permits.

Chemical and Product Testing

  • Performed numerous toxicity tests of products and chemicals to be included in Material Safety Data Sheets (MSDS).  Determined the acute and chronic toxicity thresholds of these products to aquatic organisms.



Personal tools