Methyl 12-hydroxyoctadecanoate

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

According to Regulation (EC) No. 1907/2006, Column 2 of Annex IX, toxicity testing on terrestrial organisms does not need to be conducted if direct and indirect exposure of soil is unlikely. The substance exhibits a moderate potential to adsorb to soil, based upon its predicted adsorption coefficient (Koc) of 3,663 L/kg (i.e., log Koc = 3.5638), but is below the criterion of Koc > 4 indicative of strong sorption to soil. The substance has a very low water solubility (i.e., 0.08994 mg/L) and is considered insoluble in water; therefore, partitioning of the substance to soil pore water is not expected. The substance is not expected to exhibit toxicity in the aquatic environment, as shown in short-term and/or long-term studies on an analogue substance in fish, aquatic invertebrates and algae. In addition, the substance has been shown to be readily biodegradable (i.e., 80% degradation in 28 d and meeting the 10-d window) and is not persistent in the environment; therefore, food chain exposures through secondary poisoning are not expected. Furthermore, studies conducted on analogue substances in higher vertebrates showed that the substance is not expected to exhibit acute oral toxicity, specific target organ toxicity through single or repeated dose oral exposure, genetic toxicity or reproductive toxicity. The substance is a short-chain alkyl ester of a naturally occurring fatty acid (i.e., the methyl ester of 12-hydroxystearic acid), and is expected to undergo catabolism by esterases and lipases in vivo; toxicokinetic studies conducted on analogue substances in mammals demonstrated a pharmacokinetic disposition comparable to that of endogenous triglycerides. Therefore, direct and indirect exposures of terrestrial organisms to the soil are unlikely, and toxicity testing to soil macro-organisms except arthropods is waived.

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

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data waiving: supporting information

Description of key information

According to Regulation (EC) No. 1907/2006, Column 2 of Annex IX, toxicity testing on terrestrial organisms does not need to be conducted if direct and indirect exposure of soil is unlikely.  The substance exhibits a moderate potential to adsorb to soil, based upon its predicted adsorption coefficient (Koc) of 3,663 L/kg (i.e., log Koc = 3.5638), but is below the criterion of Koc > 4 indicative of strong sorption to soil. The substance has a very low water solubility (i.e., 0.08994 mg/L) and is considered insoluble in water; therefore, partitioning of the substance to soil pore water is not expected. The substance is not expected to exhibit toxicity in the aquatic environment, as shown in short-term and/or long-term studies on an analogue substance in fish, aquatic invertebrates and algae. In addition, the substance has been shown to be readily biodegradable (i.e., 80% degradation in 28 d and meeting the 10-d window) and is not persistent in the environment; therefore, food chain exposures through secondary poisoning are not expected. Furthermore, studies conducted on analogue substances in higher vertebrates showed that the substance is not expected to exhibit acute oral toxicity, specific target organ toxicity through single or repeated dose oral exposure, genetic toxicity or reproductive toxicity.  The substance is a short-chain alkyl ester of a naturally occurring fatty acid (i.e., the methyl ester of 12-hydroxystearic acid), and is expected to undergo catabolism by esterases and lipasesin vivo; toxicokinetic studies conducted on analogue substances in mammals demonstrated a pharmacokinetic disposition comparable to that of endogenous triglycerides. Therefore, direct and indirect exposures of terrestrial organisms to the soil are unlikely, and toxicity testing to soil macro-organisms except arthropods is waived.