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Ecotoxicological information

Long-term toxicity to fish

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Administrative data

Link to relevant study record(s)

Reference
Endpoint:
fish early-life stage toxicity
Data waiving:
other justification
Justification for data waiving:
other:

Description of key information

No long-term fish toxicity tests are available for the test substance. It appears appropriate to waive this study.

Key value for chemical safety assessment

Additional information

The test substances of the methylenediphenyl isocyanate (MDI) category react quickly with water and hence could rapidly be hydrolysed in aqueous solution (T1/2 = 20h). However, MDI is hydrophobic and poorly soluble in water and thus the heterogeneous reaction with water or soil is less rapid. The major product of such a reaction is a solid, insoluble polyurea. Under conditions typical of many types of environmental contact, i. e. with relatively poor dispersion of the denser isocyanate, the interfacial reaction leads to the formation of a solid crust encasing partially or unreacted material. This crust restricts ingress of water and egress of amine, and hence slows and modifies hydrolysis.