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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

General discussion of environmental fate and pathways

Abiotic degradation

Air: Based on estimation with the QSAR model Aopwin the substance undergoes in air rapid degradation after reaction with hydroxyl radicals. The DT50 value after reaction with hydroxyl radicals is 10 hours. No reaction with ozone was estimated. Based on the half-life with hydroxyl radicals, 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 (GHS, 3rd Edition, CLP, 2008 and its amendments).

Water: The substance is not expected to hydrolyse based on absence of hydrolysable groups, and the substance is readily biodegradable.

Biotic degradation

In a Closed Bottle test (OECD TG 301D) 2.3 mg/l substance was exposed to secondary activated sludge for 28 -days. In this test 72% biodegradation was observed meeting the 14 -day time window and therefore the substance is readily biodegradable.

Bioaccumulation

Based on the log Kow of 3.2 it can be concluded that the substance has no bioaccumulation potential with calculated BCF values for aquatic and terrestrial organisms of 104.7 and 19.86 L/kg, respectively.

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 substancewas determined at 3.58 (equivalent Koc = 3760 L/kg). Based on this value it may be concluded that the substance has some potential for adsorption to solid surfaces and soil (Koc < 4).

A Henry's law constant of 2.49 Pa·m³/mol (at 12 °C) was calculated in EUSES (Vap pressure 9.3 Pa (24°C) , 158.3 molecular weight and 281.9 mg/l water solubility (24°C). Based on this value the substance has some potential to partition from water to air.

Based on Level III environmental distribution modelling using EPISUITE (assuming equal and continuous releases to air, water and soil) using the CAS number 18479-57-7, it is estimated that the majority of the substance released to the environment will partition mainly into soil (73.1%) and water (25.2%) with small amounts to air (1.5%) and sediment (0.1%).

The SimpleTreat model (4.0) simulates the distribution of the substance in a Sewage Treatment Plant. Model calculations (default assumptions) show that 65.8% of the substance will be degraded and that 9.8%, 23.7%, and 0.72% will partition to water, sludge and air, respectively.

Additional information