4,7-Decanediol, 2,4,7,9-tetramethyl-

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.053 mg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.532 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.005 mg/L

Assessment factor:

10 000

Extrapolation method:

assessment factor

PNEC marine water (intermittent releases):

0.053 mg/L

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

10 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

4.6 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.46 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

0.53 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

The PNEC_oralfor the evaluation of secondary poisoning was not calculated, based on the waiver described by ECHA(Guidance on information requirements and chemical safety assessment, Part B: Hazard assessment, Version 2.1, December 2011, Section B.7.2.7 Derivation of PNECs for predators and top predators, pp. 40-41)and the assessment whether the exposure route of secondary poisoning is relevant(Guidance on information requirements and chemical safety assessment, Chapter R.16: Environmental exposure assessment, Version 3.0, February 2016, Section R.16.4.3.8. Predators (secondary poisoning), pp. 64-65).

ECHA(Guidance on information requirements and chemical safety assessment, Part B: Hazard assessment, Version 2.1, December 2011, Section B.7.2.7 Derivation of PNECs for predators and top predators, pp. 40-41)states that a chemical which has a log Kow ≥ 3 or a BCF ≥ 100; and no mitigating property such as biodegradability or hydrolysis (half-life less than 12 hours) is generally evaluated with respect to secondary poisoning (i.e., the derivation of a PNEC_oral).

The log Kow value for this substance, is slightly above the criterion of 3 (3.8). The structural analogon Surfynol 124 has an experimentally-determined BCF of <24 (Mitsubishi Chemical Medience Corporation, 2010), which is below the BCF criterion of 100; thus the geminalic diols have a low potential for bioaccumulation. The geminalic diols have not been shown to exhibit a mitigating property, such as rapid biodegradability or hydrolysis half-life less than 12 hours. The geminalic diols have a low potential to cause toxic effects if accumulated in higher organisms, as described by ECHA(Guidance on information requirements and chemical safety assessment, Chapter R.16: Environmental exposure assessment, Version 3.0, February 2016, Section R.16.16.1.3.2. Identification of the scope of exposure assessment and type of risk characterization, pp. 22-25) These criteria include the hazard statements H360 “May damage fertility or the unborn child”, H361 “Suspected of damaging fertility or the unborn child”, H362 “May cause harm to breastfed children”, H372 “Causes damage to organs through prolonged or repeated exposure”, H373 “May cause damage to organs through prolonged or repeated exposure”.

Although the calculated BCF of 2,4,7,9-tetramethyldecane-4,7-diol was 149 L/kg, the structurally related substance 2,5,8,11-tetramethyldodec-6-yne-5,8-diol (log Kow 4.79) has an experimentally-determined BCF of <24 (Mitsubishi Chemical Medience Corporation, 2010), which is below the BCF criterion of 100; thus the acetylenic diols have a low potential for bioaccumulation. The substance has not been shown to exhibit a mitigating property, such as rapid biodegradability or hydrolysis half-life less than 12 hours.

The substance has a low potential to cause toxic effects if accumulated in higher organisms, as described by ECHA (

Guidance on information requirements and chemical safety assessment, Chapter R.16: Environmental exposure assessment, Version 3.0, February 2016, Section R.16.16.1.3.2. Identification of the scope of exposure assessment and type of risk characterization, pp. 22 -25).

Therefore, although the substance does not appear to strictly meet the criteria for waiving the PNECoral, (based on log Kow ≥ 3, and no mitigating properties such as ready biodegradability or rapid hydrolysis), it has been shown to be of low toxicity to mammals and to be non-bioaccumulative. Therefore, the secondary poisoning pathway is not relevant and a value for PNECoral was not derived.

Conclusion on classification

The substance has a low potential to cause toxic effects if accumulated in higher organisms, as described by ECHA (Section R.16.5.7.2, Chapter 16 “Environmental Exposure Estimation”, of Guidance on information requirements and chemical safety assessment, May 2008, pp. 93-94).

The most sensitive species was fish. Acute fish toxicity: LC50 (96h) = 53.2 mg ai/L. This value is used to derive the PNECs.

The substance is not readily biodegradable. The BCF was calculated to be 149 L/kg wet-wt. However, the structurally related substance 2,5,8,11-tetramethyldodec-6-yne-5,8-diol (log Kow 4.79) has an experimentally-determined BCF of <24 L/kg. Thus, the bioaccumulation criterion (BCF >= 100 L/kg) is not fulfilled.

Overall, 2,4,7,9-Tetramethyl-4,7-decanediol is not classified for acute aquatic toxicity and classified as Aquatic Chronic 3 (H412: Harmful to aquatic life with long lasting effects) based on the

LC50 (96h) = 53.2 mg ai/L in fish and the substance being not readily biodegradable in accordance with Regulation EC No 1272/2008.