Quaternary ammonium compounds, N-(C16-18 and C18-unsatd. alkyl)-N,N,N',N',N'-pentamethyltrimethylenedi-, dichlorides

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

13.98 µg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

2.38 µg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

1.4 µg/L

Assessment factor:

100

Extrapolation method:

assessment factor

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

3.2 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

55.93 mg/kg sediment dw

Assessment factor:

1

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

5.59 mg/kg sediment dw

Assessment factor:

10

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:

9.45 mg/kg soil dw

Assessment factor:

100

Extrapolation method:

assessment factor

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

PNEC oral

PNEC value:

2 mg/kg food

Assessment factor:

300

Conclusion on classification

Due to intrinsic properties of cationic surfactants river water ecotoxicity tests deliver reproducible test results with limited uncertainty which are ideal for risk assessment purposes. For classification purposes however the mitigating effect on ecotoxicity due to sorption of the amines to suspended matter, a worst-case correction factor of 10 is applied to the L(E)C₅₀ to correct for the lower ecotoxicity observed. Algae and daphnia are in general the most sensitive species for quaternary ammonium compounds but due to the use of river water the difference with the Fish LC₅₀ is mitigated. The daphnia EC₅₀serves as basis for the acute classification of N,N,N',N',N''-Pentamethyl-N-C16-18 (even numbered) C18 unsat.-alkyl-1,3 -propanediammonium chloride.

The only test result obtained in reconstituted lab water is the fish test and therefore this endpoint can directly be used for classification purposes.

Table   Available short-term fresh water test results for diquat C16 -18 

Diquat	CAS number	96 h Fish LC50 (µg/L)	72 h algae ERC10(µg/L)	72 h algae ERC50(µg/L)	21 d daphnia EC10 (µg/L)	21 d daphnia EC50 (µg/L)	EC50corr(µg/L) *	EC10corr(µg/L) *
C16 -18	1211950 -04-7	350	139.8	235	163.5	238	23.5	13.98

*corrected for Classification with Factor 10 for mitigation

the figures presented are corrected for active ingredient content of 94.5%. The fish test is performed in reconstituted lab water and this value is therefore not corrected for mitigation by river water consituents. The fish data are however corrected for the Active ingredient content (50%). For the long-term daphnia results the effects on the parents are presented. The algae results are corrected for 45% adsorption to glassware.

 

The fish test is the only test which is not performed in natural river water and is still showing the lowest tox. The degree of mitigation by the river water is corrected for classification purposes with a factor of 10. This would mean that the algae and daphnia are at least a factor of 10 more sensitive compared to fish. Fish are thus clearly less sensitive compared to algae and daphnia.

Based on the observed lower toxicity to fish not only for the diquat C16 -18 but also for primary fatty amines, mono and dialkyl quats it is considered unlikely that fish toxicity will be critical for diquat C16 -18. Hence any additional toxicity testing with fish will not add scientific value to the ecotoxicity profile of the diquat C16 -18 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 ecotoxicity data for several cationic surfactants a safety factor of 10 may be applied for the derivation of the PNEC_aquatic,bulk. In addition, the low acute to chronic ratio observed in the long-term daphnia test supports the use this lower assessment factor. The daphnia reproduction test result shows that at 810 μg/L all parental daphnids were immobile within two days, without reproduction, while at the next concentration of 270 µg/L there is no detrimental effect on reproduction when compared to the control for the surviving daphnia's. These observations result in the derivation of a NOEC of 270 µg/L reproduction resulting in a low acute-to-chronic ratio. A low acute-to-chronic ratio is indicative of a non-specific mode of action and is often associated with not systemic effects. This observation is consistent with the known effects of cationic surfactants on aquatic organisms, where toxicity is associated with physical binding to respiratory membranes. This explains the steep concentration curves seen and the lack of intermediate chronic effects on reproduction.

The toxicity to microorganisms was assessed in an OECD 209 test which resulted in a three hour EC10 of 32.1 mg a.i./L

For classification purposes Ecotoxicity, Biodegradability and Bioconcentration have to be considered. All acute ecotoxicity values are below 1 mg/L. The substance is not considered to fulfil the readily biodegradability criteria but it will have a BCF < 500 L/kg.

 

Classification according DSD (Dangerous Substance Directive 67/548/)

The acute ecotoxicity values of below 1 mg/L and the conclusion that the substance does not fulfil the readily biodegradability criteria leads to the following environmental classification for N,N,N',N',N''-Pentamethyl-N-C16-18 (even numbered) C18 unsat.-alkyl-1,3-propanediammonium chloride:

 

                                                                                      N, R50/53

 

 

Classification according CLP (Classification, Labeling & Packaging) Regulation EC No. 1272/2008The acute ecotoxicity values of below 1 mg/L and chronic ecotoxicity values of between 0.01-0.1 mg/L together with the conclusion that the substance does not fulfill the readily biodegradability criteria leads to the following environmental classification for N,N,N',N',N''-Pentamethyl-N-C16-18 (even numbered) C18 unsat.-alkyl-1,3-propanediammonium chloride:

 

                                   Acute (short-term) aquatic hazard Category 1, M-factor 10

 

The corresponding M-factor is 1 based on the EC50 of 23.5 µg/L (Algae, 72 h ErC50 of 235 µg/L and divided with correction factor of 10 for mitigation)

M factor 1

 

                                     Chronic (long-term) aquatic hazard Category 1,M-factor 1

 

The corresponding M-factor is 1 based on the lowest ErC10 of 13.98 µg/L (Algae, 72 h ErC10 of 139.8 µg/L divided with correction factor of 10 for mitigation)