Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Abiotic degradation:

Air: No experimental data on the phototransformation of the substance in air are available. Based on estimation with the QSAR model AopWin phototransformation data were calculated for alpha-Terpinyl acetate, being the main constituent of Terpinyl acetate multi, and therefore representative for Terpinyl acetate multi too. Alpha-Terpinyl acetate undergoes in air rapid degradation after reaction with hydroxyl radicals or ozone. The DT50-values after reaction with hydroxyl radicals and ozone are 1.36 hours and 0.64 hours, respectively. Terpinyl Acetate gamma shows values of 1.11 hours and 0.23 h. These values are not used in the risk characterisation because these are not experimental values.

Water: Substance is readily biodegradable and the hydrolysis potential does not need to be investigated further. The substance is an ester and therefore some hydrolysis can be expected. Conservatively, the half-life in water of the substance is expected to be > 1 year at pH 7.

Biotic degradation:

Terpinyl acetate multi is readily biodegradable based on read-across from alpha-Terpinyl acetate which was tested in OECD TG 301F. In this study activated sludge was exposed to 100 mg/L alpha-Terpinyl acetate for 28 days. In this test 63% biodegradation was observed at day 28 (58% biodegradation was observed already at day 2). Therefore, the substance is readily biodegradable.

Bioaccumulation:

Bioaccumulation testing 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. The BCFs for aquatic and terrestrial organisms were calculated using QSARs of Veith et al. (1979) and Jager (1998), both incorporated in the EUSES model, and yielded values of 1100 and 302 L/kg ww, respectively, using a log Kow of 4.4. However, it can be anticipated that simple esters, such as acetic esters, will be converted to the respective alcohols by carboxylesterases in fish liver and therefore the BCF values calculated are considered worst case values.

Transport and distribution:

The adsorption potential of the substance was determined in a study according to OECD TG 121 (HPLC method). Under the conditions of the test, the log Koc of the substance, including all peaks, was determined at 2.79 (equivalent to 620 L/kg). Based on this value the substance has moderate potential for adsorption to solid surfaces and soil.

A Henry's law constant of 10.6 Pa·m³/mol (at 12°C) was calculated in EUSES (vapour pressure of 3.634 Pa (23°C), 196.3 molecular weight and 36 mg/l water solubility (23°C). Based on this value limited partitioning from water to air may be expected.

Based on Level III environmental distribution modelling using EPISUITE (assuming equal and continuous releases to air, water and soil) using the CAS number 8007-35-0 and the physico-chemical parameters (water solubility and log Kow) as input, it is estimated that the majority of the substance released to the environment will partition mainly into soil (83%) and water (16%) with small amounts to air (<0.1%) and sediment (<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 80.4% of the substance will be degraded and that 11.1%, 5.4% and 3.1% will partition to water, sewage sludge and air, respectively.

Additional information