Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

The registered substance exhibits a dissipation time in water less than the cut-off value of 12 h and is therefore considered as hydrolytically unstable. Upon contact with water, the diisocyanate groups of IPDI react by forming amines and CO2. The amines (i.e. isophorone diamine) react further with unreacted diisocyanate groups of IPDI resulting in oligo- and subsequently polyurea components.

The log Kow of the hydrolysis product isophorone diamine (IPDA, CAS 2855-13-2) was determined according to OECD 107 as 0.99 indicating a low potential for bioaccumulation. Moreover, a BCF value of 3.16 was calculated by QSAR (BCFWin v2.14 as integrated in EPIWIN v3.10) that also indicates a low potential for bioaccumulation. Beside IPDA, polyurea components are formed that are due to their molecular size, low mobility and high log Kow not bioavailable (low potential to cross biological membranes). According to ECHA guidance R.11, a molecular weight higher than 1100 g/mol is an indicator that the aquatic BCF of the respective substance is lower than 2000. According to QSAR calculations with SRC Kowwin v1.68 Computer Program, integrated in U.S. EPA's EPI Suite (EPI Web, status 2016) the molecular weight for oligo-urea components was calculated to be >1100 g/mol for oligomers with six monomer components. In addition, the aquatic BCF of a substance is probably lower than 2000, if the calculated log Kow is higher than 10 (see ECHA guidance R.11). This also applies for polyurea components as the log Kow was calculated to be >10 for oligomers with five monomer components. Hence, the potential for bioaccumulation for IPDI and its hydrolysis products (IPDA and polyurea) can be considered as low.