Acetic acid, anhydride, reaction products with 1,5,10-trimethyl-1,5,9-cyclododecatriene

Endpoint summary

Description of key information

Abiotic degradation

Air: Based on estimation with the QSAR model AopWin, the substance undergoes rapid degradation in air after reaction with hydroxyl radicals and ozone. The half-life after reaction with hydroxyl radicals is 0.045 days (rate constant is 237.6 E-12 cm3/molecule-sec). For reaction with Ozone, the atmospheric half-life is 0.013 days (rate constant is 87.2 E-17 cm3/molecule-sec). 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: A hydrolysis study with the substance was carried out according to OECD TG 111. The substance is hydrolytically stable at pH 4, 7 and 9 at 50°C. The half-life under environmental conditions (25°C) is therefore expected to be greater than 1 year.

Biotic degradation of the substance was determined by the Sealed-Vessel CO2 Evolution test using International Standard ISO 14593 (adopted March 1999) and draft Test Guideline OECD 310 (CO2 in sealed vessels - Headspace Test). The substance was biodegraded by 0.1% at day 28. The substance is therefore not considered to be readily biodegradable.

Bioaccumulation of the substance was investigated according to OECD TG 305 in a flow-through test. The BCFKGL (lipid-normalized growth-corrected kinetic BCF) was 97 and the BCFSSL (lipid-normalized steady-state BCF value) was 94 L/kg (using a lipid correction of 0.53 based on day 31 of the uptake phase).

The bioaccumulation result for terrestrial species is based on log Kow and the calculated BCF value using the QSAR of Jager (1998) incorporated in the EUSES model, yielded a value of 4260 L/kg ww. 

Transport and distribution

The adsorption potential of the substance was investigated according to OECD TG 121 using the HPLC method under GLP. Under the conditions of the test, the major components of the substance were found to have log10 Koc values between 4.0 and 4.2.

A Henry's law constant was calculated using the equation from EUSES. Using a molecular weight of 246 g/mole, and the experimentally determined vapour pressure of 0.06 Pa (at 25 °C) and water solubility of 5.142 mg/L (at 25°C), the Henry's Law constant at 25°C and at environmental temperature (12°C) is calculated to be 2.868 and 1.374 Pa·m³/mol, respectively. This Henry coefficient shows that volatilisation is of minor importance in the environmental behaviour of the substance (see also distribution modelling).

Based on Level III distribution modelling using EPISUITE (assuming equal and continuous releases to air, water and soil) using the SMILES code CC(=O)C1CCC(C)=CCCC=C(C)CCC1=C as input, it is estimated that the majority of the substance released to the environment will partition mainly into soil (86.3%) and water (9.5%) with small amounts to sediment (4.2%) and air (<0.1%).

The SimpleTreat model, which is incorporated in EUSES simulates the distribution of the substance in a Sewage Treatment Plant based on vapour pressure, water solubility, log Koc and ready biodegradability. Model calculations show that 0% of the substance will be degraded, and that 39.28 %, 42.16%, 17.12% and 1.44% will partition to water, primary settler, surplus sludge and air, respectively.