2,2'-iminodi(ethylamine)

Toxicity to aquatic algae and cyanobacteria

Description of key information

In a growth inhibition test with Pseudokirchnerella subcapitata, the 72-hour ErC50 for diethylene triamine was 1164 mg/L.  The 72-hour NOEC for diethylene triamine was determined to be 10 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

1 164 mg/L

EC10 or NOEC for freshwater algae:

10 mg/L

Additional information

A total of four algal studies were listed under this endpoint, however three of these studies were assigned a Kilimsch score of 4 based on the unavailability of detailed study methodologies. One toxicity study with the green algae,Pseudokirchnerella subcapitata,was available for review and was found to be of good quality and reliable for use in the risk assessment process. This study measured both growth rate (r) and biomass (b) as indicators of growth inhibition over 72 hours of exposure.  The 72-hour NOEC with P. subcapitata was 10 mg/L diethylene triamine. The 72-hour E_bC50 (based on biomass) and the 72-hour ErC50 (based on growth rate) were reported as 187 and 1164 mg/L diethylene triamine, respectively. Since the use of the average specific growth rate for estimating toxicity is scientifically preferred (OECD 201, 2006), the 72-hour NOEC and ErC50 of 10 and 1164 mg/L diethylene triamine were selected as the key parameters for this endpoint.