Amines, di-C16-18-alkyl

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.879 µg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.177 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.088 µg/L

Assessment factor:

100

Extrapolation method:

assessment factor

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:

24.6 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

2.46 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:

1.22 mg/kg soil dw

Assessment factor:

1

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

1.11 mg/kg food

Assessment factor:

900

Additional information

All aquatic endpoints are based on measured data applying assessment factors. For soil and sediment PNEC is calculated using the equilibrium partition coefficient method.

The PNEC oral is based on the LOAEL from the 28-day repeated dose study with rats (age 7wk). A food conversion factor of 20 is used. The assessment factor for a 28-day study (300) is multiplied with 3, since the result is a LOAEL.

As for the aquatic tests the measured dissolved concentration was used for the derivation of the dose effect assessment, the results should be compared to the dissolved exposure concentrations.

The PNEC_aquatic is calculated using the assessment factor proposed by the TGD. As long-term NOECs from species representing two trophic levels are available (algae and daphnia) an assessment factor of 50 may be used. Fish are in general not more sensitive compared to daphnia and algae and no effects were observed to daphnia at the water accommodated fraction concentration of 48.3 µg/L. As the algae EC10 is 8.79 µg/L it is very unlikely that a long-term fish study will result in a lower EC10. Hence any additional toxicity testing with fish will not add scientific value to the ecotoxicity profile of the dialkylamines C16 -18other than for obtaining a lower assessment factor. It is therefore concluded that for scientific reasons and in accordance to REACH legislation further testing on fish has to be avoided for reasons of animal welfare. This means that it is proposed to waive the long term fish unless a further refinement of the effect assessment is considered necessary based on the outcome of the chemical safety assessment.

Based on the before mentioned facts it is considered acceptable for dialkyl amine C16 -18 to apply a safety factor of 10 for the derivation of the PNEC_aquatic.

Conclusion on classification

Environment

For classification purposes Ecotoxicity, Biodegradability and Bioconcentration have to be considered

Ecotoxicity

Table 1 Available aquatic toxicity data for the dialkylamines.

Dialkylamines	CAS number	96 h Fish LC50 (µg/L)	72 h algae ERC50(µg/L)	72 h algae ERC10/ NOEC (µg/L)	48 h daphnia EC50 (µg/L)
Amines, di-C16-18 (evennumbered) alkyl	308062-60-4	(220000)	17.7	8.8	>48.3

Figures given in bold are based on read across; figures given in italic and underlined are performed in reconstituted lab water. The values in parenthesis in grey are from Klimisch 3 studies.

 

Table 2           Environmental classification for the dialkylamines.

Substance	CAS number	Classification	M factor, chronic	M factor, acute
Amines, di-C16-18 (evennumbered) alkyl	308062-60-4	Acute Cat1 Chronic Cat1	1	10

Although the studies used as a basis for classification are performed in natural river water, no mitigating factor is applied to the results, since in the study the solubility of the substance is low, and the test was performed as the water accommodated fraction after filtering of the water to remove suspended particles.

Biodegradability

For the poorly soluble dialkylamines ready biodegradability test results in excess of 60% at day 28 are available for the short (C12) and long (C18) chain. Biodegradation in excess of 60% was not achieved in a few tests. The low biodegradability test results in these tests should be attributed to the limited bioavailability under the stringent test conditions and should consequently be ignored.

 

Table 3 Compilation of ready biodegradability test results obtained with dialkyl amines

Test substance name	Test Guideline	Result at day 28 (%)	Source
Didodecylamine	OECD 301D	>70	Ginkel et al., 1994
Amines, di-C12-18-alkyl	OECD 301D	20	Ginkel 1992
Amines, di-C12-18-alkyl	DIN 38409/ OECD 301C	25	Voelskow, 1990
Amines, di-C16-18 (evennumbered) C18 unsaturated alkyl	OECD 301D	4	Ginkel 1993
Amines, di-C16-18 (evennumbered) alkyl	OECD 301F	16	Voelskow 1996
Dioctadecylamine	OECD 301D	79	Ginkel, C.G., 2005
Dioctadecylamine	OECD 301D	68	Ginkel, C.G., 2005

 

Bioaccumulation potential

No measured BCF fish is available for the dialkylamines. Standard OECD 305 tests are technically very complicated with these strongly adsorbing, poorly soluble and readily biodegradable substances. No measured log Kow value is available and therefore the log Kow and BCF were calculated using EPIsuite v4.0 as presented in the table below.

Table 4 Estimated Log Kow and BCF

Dialkylamines	CAS number	Estimated Log Kow (KOWWIN v1.67)	Estimated BCF
Amines, di-C16-18 (evennumbered) alkyl	308062-60-4	16.52	0.893

 

All dialkylamines have log Kow values above the log Kow threshold for DSD or CLP. It is however important to note that linear QSAR relationships between log Kow and BCF are only valid for logKow<6. Above this value, these predictions will become increasingly inaccurate. This is probably due to the limited availability of the chemical as well as the increasing difficulty in crossing membranes (Opperhuizen et al, 1985, Anliker et al, 1988).The influence of the limited bioavailability is included in the calculation of the BCF with the BCFBAF v3.00. The calculated BCF results therefore most likely represent the partitioning behavior more realistically than based on the log Kow. This means the substance should be classified as R-50.

References:

1.    Anliker R, Moser P and Poppinger D, 1988. Bioaccumulation of dyestuffs and organic pigments in fish. Relationships to hydrophobicity and steric factors. Chemosphere, 17, 1631 - 1644.

2.    Opperhuizen A, vd Velde EW, Gobas FAPC, Liem DAK and v d Steen JMD, 1985.Relationship between bioconcentration in fish and steric factors of hydrophobic chemicals. Chemosphere, 14, 1871 - 1896.