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Environmental fate & pathways

Endpoint summary

Administrative data

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Additional information

1,3-Propanediol, 2,2-dimethyl-, C5-9 carboxylates (CAS 85711-80-4) is characterised by a low vapour pressure (VP < 0.001 Pa at 20 °C, SPARC (v4.6)), a low water solubility (≤ 8.7 µg/L), and a high log Koc indicating a high adsorption potential to soil and sediment particles (log Koc > 3, MCI method, KOCWIN v2.00). Based on the result of an OECD 301B study the substance is regarded as readily biodegradable (91.8% after 28 d OECD 301B). Thus, it is expected that an extensive elimination of the substance in sewage treatment plants will occur. In the case insoluble chemicals enter a standard Sewage Treatment Plant (STP), they will be extensively removed in the primary settling tank and fat trap and thus, only limited amounts will get in contact with activated sludge organisms, according to the Guidance on information requirements and chemical safety assessment, Chapter R.7b (ECHA, 2014). As a result of the high adsorption potential of the substance (log Koc > 3, MCI method, KOCWIN v2.00) a removal from the water column to a significant degree by adsorption to sewage sludge can be expected (Guidance on information requirements and chemical safety assessment, Chapter R.7b, (ECHA, 2014). In conclusion, the concentration of the substance in conventional STP effluents is presumably marginal. Abiotic degradation via hydrolysis is considered as not relevant for the substance. Calculations using HYDROWIN v2.00 predict half-lives > 1 year for the main components of the substance (Szymoszek, 2015). Moreover, the substance is not volatile (VP < 0.001 Pa at 20 °C) and thus evaporation to the air and subsequent transport through the atmosphere to other environmental compartments is not likely.

Based on the low water solubility and metabolism via enzymatic hydrolysis of the substance a relevant uptake and bioaccumulation in aquatic organisms is not expected. 1,3-Propanediol, 2,2-dimethyl-, C5-9 carboxylates will be hydrolysed and the cleavage products can be further metabolized. In conclusion, bioaccumulation and biomagnification through the food chain of the substance is not expected. This is supported by low calculated BCF values of 3.7-33.8 L/kg ww (BCFBAF v3.01, Arnot-Gobas, including biotransformation, upper trophic).