2-butoxyethanol

Short-term toxicity to aquatic invertebrates

Description of key information

Only those results deemed reliable are shown here:
Daphnia magna. 48hr EC50 = 1800mg/l (protocol: OECD202) (based on measured concentrations)
Daphnia magna. 48hr EC50 > 1000mg/l (protocol: ~OECD202)
Daphnia magna. 48hr EC50 = 2650mg/l (protocol: US EPA)
Daphnia magna. 24hr EC50 =1815mg/l (protocol: DIN 38412)
Daphnia magna. 24hr EC50 =1720mg/l (protocol: DIN 38412)
Artemia sp.. 24hr TLm =1,000mg/l (protocol: no data)
Hydra att. 92hrs IC50 (adults) = 3600mg/l (protocol: none)
Hydra att. 72hrs IC50 (adults) = 690mg/l (protocol: none)
Daphnia magna. 48hr EC50 =881mg/l (protocol: unknown.  Reassessed at 1100mg/l)
Crassostrea gigas (24hr EC50)>100mg/l, <1000mg/l (reproduction)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

690 mg/L

Additional information

A number of studies have been carried out using multiple species, both fresh and salt water. These indicate that 2 -butoxyethanol is of very low toxicity to invertebrates. Some of these studies were not performed for the normally required 48hrs (only 24hr studies) however one study was for the requisite period and to a modern protocol and in the preferred daphnia magna species and can clearly be regarded as a key study for this end point. In addition, there is reliable data in a seawater species (albeit only a 24hr study). Two studies report results for Hydra attenuata. The studies produced significantly different results to daphnia and since this is not a standardised assay, care needs to be taken in identifying it as a key study for deriving the EC50 for this end point. However, there is also a final study looked at reproductive effects in the Japanese Oyster over a 24hr exposure period. No effects were seen at 100mg/l whereas 100% of larvae were affected at 1000mg/l. This result is supportive of the Hydra result which is therefore use as a conservative estimate of the EC50 for this end point.