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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

No data are available for the submission substance, 3-(trimethoxysilyl)propiononitrile (CAS 2526-62-7). However, data are available for the structurally-analogous substance, 3-(triethoxysilyl)propiononitrile (CAS 919-31-3). The two substances share a common hydrolysis product.

Reliable short-term toxicity tests results are available for freshwater fish (Oncorhynchus mykiss), invertebrates (Daphnia magna) and algae (Pseudokirchneriella subcapitata).

The relevant values are:

Fish: LC50 (96 h): >110 mg/l (measured concentration of parent test substance).

Daphnia: EC50 (48 h): >100 mg/l (measured concentration of parent test substance).

Algae: ErC50 (72 h): >120 mg/l; ErC10: >120 mg/l; NOEC: 60 mg/l  (nominal concentration) or >74 mg/l, >74 mg/l and 37 mg/l, respectively, expressed in terms of concentration of the hydrolysis product, 3-(trihydroxysilyl)propiononitrile.

It is likely that under the flow-through conditions for the fish and invertebrate tests, the test organisms were exposed to primarily the parent read-across substance, 3-(triethoxysilyl)propiononitrile, and minor quantities of its hydrolysis products, 3-(trihydroxysilyl)propiononitrile and ethanol. While in the static algal test it is likely that the test organisms were exposed to a mixture of the parent substance and its hydrolysis products.

The read-across is supported by the Quantitative Structure Activity Relationship (QSAR) predictions for the silanol hydrolysis product, 3-(trihydroxysilyl)propiononitrile. Fish, invertebrate and algal E(L)C50 values have been estimated. The relevant values are:

Fish QSAR: LC50 (96 h): 2 800 000 mg/l.

Daphnia QSAR: EC50 (48 h): 990 000 mg/l.

Algae QSAR: EC50 (96 h): 110 000 mg/l.