Registration Dossier

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Stability

Phototransformation in air

1,2-Cyclohexanedicarboxylic acid, 4-methyl- (4-MHHPAc)

Half-life for reaction with photochemically-produced hydroxyl radicals: 30.1 hours.

Overall degradation rate constant with OH radicals= 1.10E-6 cm3/(molecule-day)

Hydrolysis

Half life - at ph 4: 1.43 minutes at 20 deg C; 2.04 minutes at 30 deg C and 0.692 minutes at 50 deg C. at ph 7: 1.90 minutes at 20 deg C; 1.26 minutes at 30 deg C and 0.327 minutes at 50 deg C. at ph 9: 1.27 minutes at 20 deg C; 1.18 minutes at 30 deg C and 0.233 minutes at 50 deg C.

 

Biodegradation

Ready biodegradability in water: 2% in 28 days

 

Bioaccumulation

The potential for bioaccumulation of 4-MHHPAc (the hydrolysis produc of 4-MHHPA) is low, less than 2.4 L/Kg, as expected from low values of log Kow for both substances.

 

Henry's Law Constant

The Henry's Law constants of 1,2-Cyclohexanedicarboxylic acid, 4-methyl- (4-MHHPAc), as hydrolysis product of hexahydro-4-methylphthalic anhydride, was considered for the environmental assessment. The value of 2.75E-4 Pa m³/mol shows that 4-MHHPAc is essentially non volatile from surface water.