Triethyl citrate

Toxicity to aquatic algae and cyanobacteria

Description of key information

The toxicity to aquatic algae was assessed in a test with Pseudokirchnerella subcapitata (reported as Selenastrum capricornutum) according to OECD 201 (2010):
EC50 (72h) > 100 mg/L (based on growth rate and yield)
NOEC (72h) ≥ 100 mg/L (based on growth rate and yield)
LOEC (72h) > 100 mg/L (based on growth rate and yield)

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

EC10 or NOEC for freshwater algae:

100 mg/L

Additional information

The acute toxicity to aquatic algae and cyanobacteria of triethyl citrate was tested according to OECD Guideline 201 and EU Method C.3 in an Algal Growth Inhibition Limit Test with the freshwater green algae Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) as test organism (2010). The study was conducted under certificated GLP compliance. The only concentration tested was nominal 100 mg test item/L. Additionally, a control was tested in parallel (test water without addition of the test item). Thus a limit test was performed in accordance with the OECD 201 to demonstrate that the test item has no inhibitory effect on the growth of the test organism up to this concentration. The study encompassed 2 treatment groups (1 dose rate of the test item, control) with six replicates per test concentration and six replicates for the control. At test start 50 mL of the test concentrations were inoculated with 5000 algal cells per mL test medium. These cells were taken from an exponentially growing pre-culture, which was set up 4 days prior to the test start under the same conditions as in the test. All calculations were carried out using a statistical software programme. Analysis of the yield and growth rate of the algal population within 72 h exposure period gave the following results: The NOE_rC (72h) and the NOE_yC (72h) were determined to be at least nominal 100 mg test item/L. The NOEC values might even be higher than this concentration, but concentrations in excess of nominal 100 mg test item/L or the limit of solubility have not been tested according to the recommendations of the test guidelines. The LOE_rC (72h), the LOE_yC (72h), the E_rC50 (72h) and the E_yC50 were clearly higher than nominal 100 mg test item/L (mean measured: clearly higher than 72 mg test item/L). No toxic effects against algae were observed at the limit of water solubility under these exposure conditions.