Reaction mass of 7539-04-0 and pentaerythritol tetrakis(3-mercaptopropionate) and 2-{3-(3-mercaptopropionyl)thiopropionyl}oxymethyl-2-(3-mercaptopropionyl)oxymethyl-1,3-propanediyl bis(3-mercaptopropionate)

Toxicity to aquatic algae and cyanobacteria

Description of key information

The acute toxicity of PEMP product to green alga was determined in accordance with OECD TG No 201 and GLP. A 2.8% inhibition at the limit concentration tested (loading rate of 100 mg/L, analytically verified to correspond with 0.88 mg/L) was deemed biologically irrelevant. The 72h-ErC50 and ErC10 were determined to be >0.88 mg/L; the NOErC 0.88 mg/L. The study was concluded to be reliable with restrictions.

Key value for chemical safety assessment

EC10 or NOEC for freshwater algae:

0.88 mg/L

Additional information

A study was performed to assess the effect of the test material on the growth of the green alga Pseudokirchneriella subcapitata.The method followed the OECD TG No 201 and GLP. Pseudokirchneriella subcapitatawas exposed to a loading rate of 100 mg/L (six replicate flasks) and a control (six replicate flasks) for 72 hours, under constant illumination and shaking at a temperature between 22 and 24 °C.

Analyses showed that the initially measured concentration of 0.88 mg/L of the 100 mg/L loading rate was stable during the 72 -hour test period.

Statistically significant inhibition of growth rate was found at the limit concentration, however the 2.8% inhibition was deemed biologically irrelevant. The 72h-ErC50 and ErC10 were determined to be >0.88 mg/L; the NOErC 0.88 mg/L.

The study was conducted without deviations that influence the quality of the results. However, since the analytical method used did not meet all validation criteria, the resulting measured concentrations of the test item in the test medium can only be taken as indicative. The study is concluded to be reliable with restrictions as the order of magnitude of the measured concentrations is considered to be trustworthy.