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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

There is only limited data available on the environmental fate of Fatty acids, montan-wax, stearyl esters (CAS 68308-30-5). Therefore, log Koc values for the adsorption potential as well as BCF values for the aquatic bioaccumulation potential were predicted by (Q)SAR calculations.

Fatty acids, montan-wax, stearyl esters (CAS 68308-30-5) is characterized by a molecular weight of 270.49 to 987.74 g/mole, low water solubility (< 0.539 mg/L, 20 °C, OECD 105), low estimated vapour pressure (< 0.0001 Pa, 20 °C, SPARC v5.6) and a high estimated log Koc (> 10.0, KOCWIN v2.00). Furthermore, the substance is not readily biodegradable (28% in 28 d, OECD 301 F). Thus, abiotic degradation via hydrolysis and phototransformation in air are not relevant environmental fate pathways due to low solubility and low vapour pressure, respectively.

If released into the aquatic environment, only low concentrations of the substance are expected to dissolve in the water phase. Rather, the substance is expected to sorb to organic matter, leading to an effective reduction of its bioavailability in the water column. Therefore, sediment and soil are expected to be its main compartments of environmental distribution.

Based on the substance properties and environmental distribution, the most relevant potential route of uptake by aquatic organisms is expected to occur via contact with or ingestion of particle-bound substance. However, its bioavailability in the sediment compartment is presumably very low based on its intrinsic physico-chemical properties (e.g. high sorption). Furthermore, the parent compound is expected to biotransform via enzymatic hydrolysis catalyzed by ubiquitous carboxylesterases. The hydrolysis products (constituent fatty acids and alcohols) are readily absorbed and undergo further metabolization and/or take on vital cellular functions (e.g. energy supply and storage, lipid bilayer formation). Thus, in the case of uptake and absorption by aquatic organisms, long-chain aliphatic esters are expected to be enzymatically hydrolyzed by ubiquitouscarboxylesterases, yielding the corresponding alcohols and fatty acids. Both hydrolysis products are expected to be metabolized and excreted by aquatic organisms. The metabolization of the hydrolysis products in fish is well established and not of concern in terms of bioaccumulation(Heymann, 1980; Lech & Bend, 1980; Lech & Melancon, 1980; Murphy & Lutenske, 1990; Sand et al., 1973).

Experimental data for bioaccumulation is not available for Fatty acids, montan-wax, stearyl esters (CAS 68308-30-5)and the estimated log Kow is high (> 10.0, SPARC v4.6), which may be indicative of a potential for aquatic bioaccumulation. However, the screening value for aquatic bioaccumulation based solely on log Kow presumably overestimates the true bioaccumulation potential of the substance since it does not account for the environmental fate and toxicokinetic behaviour (absorption, distribution metabolization and excretion) of the substance in living organisms. According to current knowledge, a log Kow of 10.0 or above is taken as an indicator of reduced bioconcentration (R.7c and R.11, ECHA, 2017). Substances with log Kow values above 9.3 are generally predicted to have BCF values of maximum 2000 L/kg (R.11, ECHA, 2017). The predicted BCF values for this substance provide additional evidence that the potential for bioaccumulation in aquatic organisms is low. All models consistently predicted very low BCF values of maximally 28.18 L/kg, which are clearly below the threshold values of 2000 L/kg and 5000 L/kg for bioaccumulative and very bioaccumulative substances, respectively, as laid down by REACH Regulation (EC) 1907/2006 (Annex XIII, section 1).

Thus, a significant uptake and bioaccumulation of the substance in aquatic organisms is not expected based on the extremely high log Kow, environmental and toxicokinetic behaviour, as well as on (Q)SAR predictions for bioconcentration.

 

In summary, in the case of absorption by aquatic organisms, the substance is expected to be rapidly hydrolyzed to the respective fatty acid and fatty alcohol components by ubiquitous carboxylesterases. Based on the available information, the potential for aquatic bioaccumulation of both the substance as well as its metabolites is expected to be low. Thus, the available information on environmental behavior, metabolism and bioaccumulation suggest that the overall potential for aquatic bioaccumulation of the target substance is low. Further information refer to the IUCLID chapters on bioaccumulation as well as on toxicokinetics, metabolism and distribution.

 

 

REFERENCES

Heymann, E. (1980): Carboxylesterases and amidases. In: Jakoby, W.B., Bend, J.R. & Caldwell, J., eds., Enzymatic Basis of Detoxication, 2nd Ed., New York: Academic Press, pp. 291-323.

Lech, J., Melancon, M. (1980): Uptake, metabolism, and deposition of xenobiotic chemicals in fish. EPA-600 3-80-082. U.S. Environmental Protection Agency, Duluth, MN, USA.

Lech, J.J. & Bend, J.R. (1980): Relationship between biotransformation and the toxicity and fate of xenobiotic chemicals in fish. Environ. Health Perspec. 34, 115-131.

Murphy, P.G., Lutenske, N.E. (1990): Bioconcentration of haloxyfop-methyl in bluegill (Lepomis macrochirus Rafinesque). Environ. Intern. 16, 219-230.

Sand, D.M., Rahn, C.H., Schlenk, H. (1973): Wax esters in fish: Absorption and metabolism of oleyl alcohol in the gourami (Trichogaster cosby). J Nutr 103: 600-607.