Quaternary ammonium compounds, di-C14-18-alkyldimethyl, Me sulfates

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

1. SOFTWARE
EPISUITE v4.11

2. MODEL (incl. version number)
BIOWIN v4.10

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
Dimethyl-dihexadecyl ammonium (C34) [Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCC
Dimethyl-hexadecyl-heptadecyl ammonium (C35) [Cl-].CCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCCC
Dimethyl-diheptadecyl ammonium (C 36) [Cl-].CCCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCCC
Dimethyl-heptadecyl-octadecyl ammonium (C37) [Cl-].CCCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCCCC
Dimethyl-dioctadecyl ammonium (C 38) [Cl-].CCCCCCCCCCCCCCCCCC[N+](C)(C)CCCCCCCCCCCCCCCCCC

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
- Defined endpoint:
Aerobic and anaerobic biodegradation

for further details see attached information

5. APPLICABILITY DOMAIN
- Descriptor domain:
Molecular weight, structural features

- Similarity with analogues in the training set:
When a structure contained none of the fragments occurring in the training or validation sets of the 7 used models, for which coefficients were developed, the program could not estimate the probability. With the inclusion of the molecular weight parameter, estimates are possible for all structures. Thus, exceeding molecular weight reveales unreliable predictions. Since the substance contains fragments which are included in either the training set or the validation set predictions are considered to be reliable.

6. ADEQUACY OF THE RESULT
The substance falls within the range of reliable predictivity (molecular weight of the constituents ranging from 229.45 to 790.54 g/mol, weighted mean ca. 467 g/mol). Quaternary amines are contained in the trainign set. Therefore, the result of the estimation is considered to be sufficient to fulfil the information requirements.

Principles of method if other than guideline:

prediction of biodegradation using Episuite v4.11, BioWin v4.10

GLP compliance:

no

Oxygen conditions:

aerobic/anaerobic

Key result

Remarks on result:

not readily biodegradable based on QSAR/QSPR prediction

Ready Biodegradability Prediction: (YES or NO)

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 Criteria for the YES or NO prediction: If the Biowin3 (ultimate survey  model) result is "weeks" or faster (i.e. "days", "days to weeks", or  "weeks" AND the Biowin5 (MITI linear model) probability is >= 0.5, then  the prediction is YES (readily biodegradable). If this condition is not  satisfied, the prediction is NO (not readily biodegradable). This method  is based on application of Bayesian analysis to ready biodegradation data  (see Help). Biowin5 and 6 also predict ready biodegradability, but for degradation in the OECD301C test only; using data from the Chemicals Evaluation and Research Institute Japan (CERIJ) database.

 

Summary:

	Results of single models	Ready Biodegradability Prediction:
Dimethyl-dihexadecyl ammonium (C34)	Biowin1 (Linear Model Prediction)   : Biodegrades Fast   Biowin2 (Non-Linear Model Prediction): Does Not Biodegrade Fast   Biowin3 (Ultimate Biodegradation Timeframe): Weeks-Months   Biowin4 (Primary Biodegradation Timeframe): Days-Weeks   Biowin5 (MITI Linear Model Prediction)   : Readily Degradable   Biowin6 (MITI Non-Linear Model Prediction): Readily Degradable   Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast	NO
Dimethyl-hexadecyl-heptadecyl ammonium (C35)	Biowin1 (Linear Model Prediction)   : Biodegrades Fast   Biowin2 (Non-Linear Model Prediction): Does Not Biodegrade Fast   Biowin3 (Ultimate Biodegradation Timeframe): Weeks-Months   Biowin4 (Primary Biodegradation Timeframe): Days-Weeks   Biowin5 (MITI Linear Model Prediction)   : Readily Degradable   Biowin6 (MITI Non-Linear Model Prediction): Readily Degradable   Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast	NO
Dimethyl-diheptadecyl ammonium (C 36)	Biowin1 (Linear Model Prediction)   : Biodegrades Fast   Biowin2 (Non-Linear Model Prediction): Does Not Biodegrade Fast   Biowin3 (Ultimate Biodegradation Timeframe): Weeks-Months   Biowin4 (Primary Biodegradation Timeframe): Days-Weeks   Biowin5 (MITI Linear Model Prediction)   : Readily Degradable   Biowin6 (MITI Non-Linear Model Prediction): Readily Degradable   Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast	NO
Dimethyl-heptadecyl-octadecyl ammonium (C37)	Biowin1 (Linear Model Prediction)   : Biodegrades Fast   Biowin2 (Non-Linear Model Prediction): Does Not Biodegrade Fast   Biowin3 (Ultimate Biodegradation Timeframe): Weeks-Months   Biowin4 (Primary Biodegradation Timeframe): Days-Weeks   Biowin5 (MITI Linear Model Prediction)   : Readily Degradable   Biowin6 (MITI Non-Linear Model Prediction): Readily Degradable   Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast	NO
Dimethyl-dioctadecyl ammonium (C 38)	Biowin1 (Linear Model Prediction)   : Biodegrades Fast   Biowin2 (Non-Linear Model Prediction): Does Not Biodegrade Fast   Biowin3 (Ultimate Biodegradation Timeframe): Weeks-Months   Biowin4 (Primary Biodegradation Timeframe): Days-Weeks   Biowin5 (MITI Linear Model Prediction)   : Readily Degradable   Biowin6 (MITI Non-Linear Model Prediction): Readily Degradable   Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast	NO

Interpretation of results:

not readily biodegradable

Conclusions:

Di-C14-18 alkyldimethyl ammonium methosulfate is predicted to be not readily biodegradable (Episuite v4.11, BioWin v4.10).

Reference 2

Endpoint:

biodegradation in water: screening test, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across is based on the hypothesis that source and target substances have similar toxicological properties because
• they are manufactured from similar or identical precursors under similar conditions
• they share structural similarities with common functional groups: quaternary ammonium and saturated or unsaturated alkyl chains with comparable length (corresponding to scenario 2 of the read-across assessment framework)

The read-across hypothesis is based on structural similarity of target and source substances. Based on available experimental data, including key physicochemical properties and data from acute toxicity, irritation, sensitization (human) and genotoxicity studies, the read-across strategy is supported by a quite similar toxicological profile of all substances.

Therefore, read-across from the existing ecotoxicity, environmental fate and toxicity studies conducted with the source substances is considered as an appropriate adaptation to the standard information requirements of the REACH Regulation for the target substance, in accordance with the provisions of Annex XI, 1.5 of the REACH Regulation.

A justification for read-across is attached to IUCLID section 13.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See justification for read-across attached to IUCLID section 13.

3. ANALOGUE APPROACH JUSTIFICATION
See justification for read-across attached to IUCLID section 13.

4. DATA MATRIX
See justification for read-across attached to IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Oxygen conditions:

aerobic

Key result

Remarks on result:

other: not readily biodegradable

Interpretation of results:

not readily biodegradable

Conclusions:

Di-C14-18 alkyldimethyl ammonium methosulfate is considered to be not readily biodegradable based on reliable data from a structurally closely related substance.

Description of key information

not readily biodegradable (Episuite v4.11, BioWin v4.10)

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Di-C14-18 alkyldimethyl ammonium methosulfate is predicted to be not readily biodegradable (Episuite v4.11, BioWin v4.10).

 

Supporting data are available for a structurally closely related substance. A justification for read-across is attached to IUCLID section 13.

Results on biodegradation of DODMAC are summarised in EU RAR, 2002 "It is shown in several tests that DODMAC/DHTDMAC are not readily biodegradable and there is no standard guideline test from which inherent biodegradability could be concluded.

Adaptation seems to be necessary for significant degradation but even then mineralisation is very slow. In river water tests with adapted inocula degradation is occurring with a half-life in the range of several weeks. In two cases degradation discontinued after 63 days reaching approx. 10% at a lower and 20% at a higher DODMAC concentration. In another study a degradation half-life of approx. 80 days could be derived. Based on these results a degradation constant kbiowater = 0.0047 d-1 can be extrapolated for surface water, which would correspond to inherently biodegradable substances (DT50 = 150 days). With this value it is taken into account that the lower DODMAC concentrations in surface waters are degraded slower than in the cited tests probably. DT50-values of <80 days from river water tests with added adapted sediment reveal situations where the concentration of biodegrading microorganisms is increased over the normal level. Therefore these results can not be used for the derivation of the degradation rate constant in surface waters. Most of the data referring to the elimination in wastewater treatment plants do not distinguish between biodegradation and adsorption."

Elimination ranged from 70 to 95% in different tests; the elimination is mainly attributable to adsorption.

[Type of water: freshwater]