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Cited from SIAR for SIAM 18 (Paris, April 2004): "No studies with respect to these endpoints have been performed."

Human toxicokinetic inhalative in vivo data from the substance Isophorone diisocyanate (CAS: 4098-71-9) is available that can be used to describe some toxikokinetic properties of Isophorone diamine, because Isophorone diisocyanate hydrolyses rapidly and spontaneously to the corresponding amine (Isophorone diamine) after ingestion into the body. Partly cited from SIAR for SIAM 23 (Jeju, Korea, October 17-20, 2006): "Three healthy male volunteers were exposed in a 5.6 m3exposure chamber to 3-isocyanatomethyl-3,5,5-trimethyl- cyclohexyl isocyanate concentrations of 0.0121, 0.0177, and 0.0507 mg/m3for 2 hours at day 1, 3, and 5, respectively. All urine was collected for 16 days, and blood samples were taken before and half an hour after exposure, and daily on exposure-free days. After hydrolysis (…note: here hydrolysis with 3M NaOH during 4 hours…) 3-isocyanatomethyl-3,5,5-trimethyl- cyclohexyl isocyanate was determined as 3-aminomethyl-3,5,5-trimethylcyclo- hexylamine. When working up samples from exposed persons without hydrolysis, no 3-aminomethyl-3,5,5-trimethylcyclohexylamine was seen. This indicates that the test substance was available in the urine only as conjugates. Hydrolysis had to split the conjugates and convert any residual isocyanate functions that might have been stabilized by conjugation, to amine functions. The average urinary elimination half-time was 2.8 hours. The average urinary excretion of the corresponding amine was 27% (range 19 -46%). An association between the estimated inhaled dose and the total excreted amount was seen. No 3-aminomethyl-3,5,5-trimethylcyclo- hexylamine was found in hydrolyzed plasma (Tinnerberg et al., 1995)." The experimental study results derived from Isophorone diisocyanate indicate that Isophorone diamine may be predominantly eliminated via the urine with an average urinary elimination half-time of 2.8 hours. Furthermore the experimental findings indicate that Isophorone diamine is present only as conjugates in the urine.

Because of the low partition coefficient n-octanol/water (log Pow=0.99) and because of the low calculated bioaccumulation factor (BCF=3.16) a significant accumulation of Isophorone diamine in the organism is not expected.