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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

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Administrative data

Link to relevant study record(s)

Description of key information

Measured data: EC50, 96hr: monoethylene glycol 6500-13000mg/l

TGK (~EC5), 8 day: diethylene glycol: 2700,

Sodium acetate EC0>2500mg/L (and likely >6250mg/L.)

QSAR values: 96hr EC50: 3500, 9400, 4400mg/l respectively for MEG, DEG and NaAc.

QSAR Chv values: 291, 707, 9680mg/l respectively for MEG, DEG and NaAc.

Key value for chemical safety assessment

EC50 for freshwater algae:
6 500 mg/L

Additional information

Test data is available for two of the three constituents of this substance. However, one of the studies used 8 day testing protocols that are now regarded as unreliable (growth in exponential state cannot be maintained over such a period.) QSAR data suggests that toxicity decreases with increasing molecular weight of the ethylene glycol series and therefore predicts that monoethylene glycol (MEG) will be the most toxic. The QSAR does not include a specific class covering acetate salts but predicts that the same neutral organics class can be used as an alternative. The QSAR predicts that sodium acetate will be less toxic that MEG, which confirms that the reliable measured data from MEG can be used as a conservative alternative to predict the overall toxicity of the substance. The available measured data on sodium acetate (only suitable for use as a weight of evidence approach) is consistent with this conclusion.  The lowest end of the range of the 96hr EC50 values for MEG is therefore used as a conservative value for the EC50 of the substance.