Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Reliable short-term toxicity tests results are available for the effects of the test substance on freshwater fish (Oncorhynchus mykiss and Oryzias latipes), and algae (Selenastrum capricornutum (new name: Pseudokirchneriella subcapitata)). Studies for invertebrates (Daphnia magna) exist but were not considered to be reliable. However, in accordance with Column 2 specific rules for adaptation from Column 1 of Annex VII of the REACH Regulation, the short-term invertebrate study does not need to be conducted because a long-term aquatic toxicity study on invertebrates is available.

A 96-hour LC50 value of 0.46 mg/l (expressed as measured concentration) has been determined for effects on mortality of O. mykiss.

A 48-hour LC50 value of 1.27 mg/l (expressed as nominal concentration) has been determined for effects on mortality of O. latipes.

A 70-hour ErC50 value of >0.55 mg/l and ErC10 of 0.09 mg/l have been determined for the effects of the substance on growth rate of S. capricornutum.

In a long-term test a 21-day EC50 value of 0.30 mg/l and NOEC of 0.08 mg/l have been determined for the effects of the substance on reproduction of Daphnia magna.

No reliable experimental test results are available for long-term toxicity of HMDS to fish. A read-across 90-day NOEC of ≥27 μg/l (0.027 mg/l) has been determined for the effects of structurally-similar substance octamethyltrisiloxane (L3, CAS 107-51-7) on early-life stages of Oncorhynchus mykiss.

An estimated chronic NOEC of 0.020 mg/l for fish for HMDS is available using a reliable QSAR method.

Three reliable studies are available for toxicity to microorganisms.

Two reliable studies are ASRI (activated sludge respiration inhibition) studies. The key study was chosen as the most recent study. This study gave a result of NOEC (3 h) ≥100 mg/l; EC50>100 mg/l. The result from the other reliable ASRI study was EC50 (3 h) >2000 mg/l.

A reliable study for growth inhibition for Pseudomonas putida is also available. The result was EC50 (17 h) >100 mg/l.