I'd like to connect with anyone that has issue regarding the subject matter.  Our NPDES permit requires the City to use T. gratilla, a sea urchin to test for the whole effluent toxicity test. Performance is best on how the in lab serial diluted wastewater compares with the controls (NOEC) and a significant difference results in a permit violation if it occurs before the dilution for our outfall.  We have gone through a Toxicity reduction evaluation plan documentation and performed the toxicity identification evaluation. All indications may point to anionic and nonanionic surfactant.  You can drop me an email at cjaramilla@honolulu.gov or call me at 808-768-3253.

Aloha.

CJ