Quaternary ammonium compounds, C12-18-alkylbis(hydroxyethyl)methyl, chlorides

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

12.1 µg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

4.14 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

1.21 µg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

1.09 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

61.4 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

6.14 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:

30.6 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

PNECs are based on the following data for the test substance:

Test type	Results
Microorganisms, activated sludge	3h-EC10respiration: 10.9 mg/L
Short-term studies
Daphnia magna	21d-EC50: 0.465 mg/L
Danio rerio	96h-LC50: 1.84 mg/L
Pseudokirchneriella subcapitata	72h-ErC50: 0.414 mg/L
Chronic studies
Pseudokirchneriella subcapitata	72h-ErC10: 0.121 mg/L
Daphnia magna	21d-NOECreprod: 0.268 mg/L

The PNEC freshwater has been derived on the basis of aquatic toxicity data determined in tests employing river water. The river water data are based on nominal concentrations. The rationale behind the use of river water tests is the strong sorption to organic matter and test vessels of the substance. The derived PNEC_bulkwill be compared to the PEC_bulk(which includes the fraction adsorbed onto suspended matter) in the risk characterisation. The same approach has been used for other cationic surfactants.

The PNECaquatic bulk is calculated using the assessment factor proposed by the REACH guidance. As long-term NOECs from species representing two trophic levels are available (algae and daphnia) an assessment factor of 50 may be used. However based on the observed lower toxicity to fish in acute tests, it is considered unlikely that long term fish toxicity will be critical for the PNEC derivation. Hence any additional toxicity testing with fish will not add scientific value to the ecotoxicity profile other 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 and that based on the weight of evidence available on the ecotoxicity data it is justified to apply a safety factor of 10 for the derivation of the PNECaquatic,bulk. With the same motivation, AF of 100 has been used for the derivation of PNEC marine.

No tests were performed with sediment organisms or terrestrial organisms. The PNECs for those compartments were derived using the equilibrium partitioning theory and Koc. All relevant substance characteristics were entered into EUSES version 2.1.2 to produce PNECsediment for the freshwater and marine compartment as wel as PNECsoil. Since PNECfreshwater is based on the bulk concentration present in surface water, a recalculation was necessary to PNECfreshwater,_dissolved before application of the equilibrium partitioning method. The following equation was used:

PNECfreshwater,_dissolved = PNECfreshwater,_bulk/ (1+ Kp_susp*SUSP_water*10^-6)

where PNECfreshwater,_bulk = 12.1 µg/L,

Kp_susp= 5496 L/kg (EUSES) and

SUSP_water = 15 mg/L.

The resulting PNECfreshwater,_dissolved = 11.2 µg/L. PNECfreshwater,sediment, PNECmarine, sediment and PNECsoil were then calculated with EUSES employing PNECfreshwater,_dissolved of 11.2 µg/L.

The PNEC for sediment is than calculated applying the EPM:

PNEC_sed         =                      K_susp-water* PNEC_{aquatic dissolved}* 1000 * 1 / RHO_susp

                                               Where: PNEC_{aquatic dissolved}             =      11.2 µg/L

                                                            K_susp-water                        =      1374 m³/m³

                                                            RHO_susp                           =      1150 kg/m³(TGD, equ. 18)

                                     PNEC_sed-EPM                     = 13.35 mg/kg ww

                                                                                 = 61.4 mg/kg dw

Despite of the low bioaccumulation potential a PNECoral can be calculated using the acute NOAEL of 18.75 mg/kg bw a.i.

PNECoral = (NOAEL * Conv_mammal)/AF = (18.75*20)/300 = 1.25 mg/kg

Conv_mammal = 20 (Rat > 6 weeks)

AF = 300 (acute study)

Conclusion on classification

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

Ecotoxicity

Due to intrinsic properties of quaternary ammonium ethoxylates, river water ecotoxicity tests deliver reproducible test results with limited uncertainty. As river water has a mitigating effect on ecotoxicity due to sorption of the quaternary ammonium ethoxylates to DOC and suspended matter, a factor of 10 should be applied to the L(E)Cx and NOEC to correct for the lower ecotoxicity observed. Algae are in general the most sensitive species and are therefore the basis for classification of the quaternary ammonium, C12-18-alkylbis(hydroxyethyl)methyl, chloride. It should be noted that the 21day-daphnia EC50 is included in the table below for classification purposes as a worst-case for acute toxicity in river water tests.

The classification is based on the following aquatic toxicity data for the test substance:

Test type	Results	Correction for river water with factor 10
Short-term studies
Danio rerio	96h-LC50: 1.84 mg/L
Daphnia magna	21d-EC50immobility: 465 µg/L	46.5 µg/L
Pseudokirchneriella subcapitata	72h-ErC50: 413.5 µg/L	41.4 µg/L
Chronic studies
Daphnia magna	21d-NOECreprod: 268 µg/L	26.8 µg/L
Pseudokirchneriella subcapitata	72h-ErC10: 121 µg/L	12.1 µg/L

 

Biodegradability

The substance is rapidly biodegradable in the environment as demonstrated with a Closed bottle test according to OECD TG 301 D. The biodegradation percentage was 70% after 28 days.

Bioaccumulation potential

The very low log Kow of -0.12 suggests that the substance has a low bioaccumulation potential.

Conclusion classification according to CLP Regulation 1272/2008

Based on the results of the acute aquatic toxicity (values < 1 mg/L) the substance is classified with Category Acute 1 (M-factor 10).

Based on the results of the chronic aquatic toxicity ( 0.01 < ErC10 < 0.1 mg/L) and since the substance has a low bioaccumulation potential and is rapidly biodegradable, the substance is classified with Category Chronic 2 (no M-factor). 

Classification according to 67/548/EEC (DSD)

Acute aquatic toxicity is < 1 mg/l and the substance is rapidly biodegradable and has a low bioaccumulation potential (log Kow of -0.12). Therefore the substance is classified with N:R50.