Reaction mass of 3-(4-hydroxy-4-methylpentyl)cyclohex-3-ene-1-carbaldehyde and 4-(4-hydroxy-4-methylpentyl)cyclohex-3-ene-1-carbaldehyde

Endpoint summary

Description of key information

Abiotic degradation:

Air: Based on estimation with the QSAR model Aopwin the substance undergoes in air rapid degradation after reaction with hydroxyl radicals and ozone. The DT50 value after reaction with hydroxyl radicals is 3.03 hours and for ozone it was estimated 0.64 hours. Based on these half-lives, the substance will not reach the stratosphere and is therefore not considered to be a long-range transported chemical in air. The substance does not have an ozone depletion potential because it does not contain halogens and does not have the potential to reach the stratosphere (EU CLP, EC no 1272/2008 and its amendments).

Water: The substance is readily biodegradable and therefore experimental hydrolysis information is not available. On structural grounds it can be anticipated that the substance is hydrolytically stable as the substance does not contain any hydrolysable groups. Therefore, the hydrolytical half-life is considered to be > 1 year at all pH's.

Biotic degradation:

In a biodegradation screening study (OECD TG 301D), 63% biodegradation was found after 28 days, which is fulfilling the 14 -day time window. This result indicates that the test substance is readily biodegradable.

Bioaccumulation:

Bioaccumulation test on aquatic species is waived based on the fact that the available information (log Kow and calculated BCF values) is deemed sufficient for the PBT assessment, classification and labelling and the chemical safety assessment.

Bioaccumulation for aquatic species is based on the log Kow and the calculated BCF value using the Veith equation, incorporated in the EUSES model, yielded a value of 12.2 L/kg ww.

Bioaccumulation result for terrestrial species is based on the log Kow and the calculated BCF value using QSAR of Jager (1998), incorporated in the EUSES model yielded a value of 2.35 L/kg ww.

Transport and distribution:

The adsorption potential of the substance was calculated from the log Kow using the equation from EUSES (non-hydrophobics QSAR, because the log Kow < 3). The calculated Koc value is 129 L/kg (log Koc = 2.1). Based on this value, the substance has low potential for adsorption to solid surfaces and soil.

A Henry's law constant of 1.81E-04 Pa·m³/mol (at 12 °C) was calculated in EUSES (Vapour pressure 5.504E-03 Pa, 210.3 g/mol molecular weight and 3.42E+03 mg/L water solubility (both at 23 °C). Based on this value the substance has no potential to partition from water to air under environmental conditions (12°C).

Based on Level III environmental distribution modelling using EPISUITE (assuming equal and continuous releases to air, water and soil) using the CAS number 31906-04-4 and the measured physico-chemical parameters (3.42E+03 mg/L water solubility and 2.1 log Kow) as input, it is estimated that the majority of the substance released to the environment will partition mainly into soil (68.3%) and water (31.6%) with small amounts to air (0.0124%) and sediment (0.0924%).

The SimpleTreat model, which is incorporated in EUSES, simulates the distribution of the substance in a Sewage Treatment Plant (STP) based on vapour pressure, water solubility, log Koc and ready biodegradability. Model calculations show that 86.3% of the substance will be degraded and that 7.24E-05%, 12.5% and 1.2% will partition to air, water and sewage sludge, respectively.