N'-(1,3-dimethylbutylidene)-3-hydroxy-2-naphthohydrazide

Toxicity to soil microorganisms

Administrative data

Endpoint:

toxicity to soil microorganisms

Type of information:

other: Statement

Adequacy of study:

key study

Study period:

Nov 2019

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 4, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This study was performed according to the OECD guidelines and based on the GLP principles.

Qualifier:

according to guideline

Guideline:

other: Directive 87/302/EEC, Part C, L133

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

not required

Details on sampling:

not applicable

Vehicle:

no

Details on test solutions:

BMH was added directly and quantitatively to the test vessels. The nominal test concentration was 100 mg/l , corresponding with 50 mg of BMH added quantitatively to test bottles with a final volume of 0.5 l.

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

The sludge was coarsely sieved, washed and diluted with tap-water. A small amount of the sludge was weighed and dried at ca. 105°C to determine the amount of suspended solids (3.4 g/l of sludge, as used for the test). Before use the pH was checked (measured value: 7.6). The batch of sludge was used on subsequent days (maximum four days). An amount of 50 ml of synthetic sewage feed was added to each litre of activated sludge at the end of each working day. The sludge was kept aerated at test temperature until use.

Test type:

other: aerobic

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

0.5 h

Post exposure observation period:

a well mixed sample of the contents was poured into a 300 ml oxygen bottle, and the flask was sealed with an oxygen electrode connected to a recorder, forcing the air out of the vessel. Oxygen consumption was measured and recorded for approximately 10 min. During measurement, the sample was not aerated but continuously stirred on a magnetic stirrer.
The pH was determined in the remaining part of the reaction mixture

Test temperature:

18.1°C

pH:

7.0-7.2

Dissolved oxygen:

initially 7.1-7.6 for the test substnace and control and between 7.1-9.1 for the reference substance

Nominal and measured concentrations:

nominal 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: All glass, 500 ml beakers and 300 ml oxygen bottles
- Type (delete if not applicable): closed
- Aeration: Clean, oil-free air.
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 3

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Tap-water purified by reverse osmosis (Milli-RO) and subsequently passed over activated carbon and ion-exchange cartridges (Milli-Q) (Millipore Corp., Bedford, Mass., USA).

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Respiration rate :the oxygen consumption of aerobic activated sludge or waste water micro-organisms expressed generally as mg O2 per litre per hour.
EC50:the concentration of the test substance at which the respiration rate is 50% of the respiration rate of the controls under the conditions of the test

TEST CONCENTRATIONS
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: given that only 10% respiration inhibition was observed at 100 mg/L, no further testing was considered necessary.

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Duration:

30 min

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Duration:

30 min

Dose descriptor:

EC10

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

Exposure of activated sludge bacteria in duplicate to a BMH concentration of 100 mg/l resulted in respiration rates of 36 and 37 mg O2/l/hr respectively. Relative to average control respiration (i.e. mean respiration rate of C2 and C3: 41 mg O2/l/hr) inhibition percentages of 11% and 9% respectively were calculated. Hence, the average inhibition percentage was 10% and therefore considered being of no biological significance. Therefore, no further testing was needed.

The respiration rates of the controls were within 15% of each other. The EC50 of the reference substance, 3,5-dichlorophenol, was 9 mg/l. Therefore, the test was considered to be valid.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: The EC50 of the reference substance, 3,5-dichlorophenol, was 9 mg/l. Four concentrations were tested: 1.0, 3.2, 10 and 32 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

The influence of BMH on the respiration rate of activated sludge was investigated after a contact time of 30 minutes.
Exposure of activated sludge bacteria in duplicate to a BMH concentration of 100 mg/l resulted in respiration rates of 36 and 37 mg O2/l/hr respectively. Relative to average control respiration (i.e. mean respiration rate of C2 and C3: 41 mg O2/l/hr) inhibition percentages of 11% and 9% respectively were calculated. Hence, the average inhibition percentage was 10% and therefore considered being of no biological significance. Therefore, no further testing was needed.
 
The respiration rates of the controls were within 15% of each other. The EC50of the reference substance, 3,5-dichlorophenol, was 9 mg/l. Therefore, the test was considered to be valid.

The test substance was not toxic to waste water (activated sludge) bacteria at a concentration of 100 mg/l nominal.

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

04 May 2001

Reliability:

2 (reliable with restrictions)

Qualifier:

according to guideline

Guideline:

other: The adsorption / desorption of the test substance has been calculated using the method described in the Technical Guidance Document on Risk Assessment (1996)

GLP compliance:

no

Type of method:

other: QSAR

Media:

soil

Type:

log Koc

Value:

1.63 dimensionless

Remarks on result:

other: mean log Koc; Range: 1.16-1.97 based on log Kow of BMH

Type:

Koc

Value:

42 dimensionless

Remarks on result:

other: derived from mean log Koc (calculation)

When applying the various QSAR's of the several chemical classes and using the Log P_ow of the major component, i.e. 1.7, the following calculated Log K_oc are obtained:

 

hydrophobics (I)        Log K_oc = 0.81 Log P_ow + 0.10 = 1.48

alcohols (II)              Log K_oc = 0.39 Log P_ow + 0.50 = 1.16 

phenols (III)              Log K_oc = 0.63 Log P_ow + 0.90 = 1.97

acetanilide (IV)          Log K_oc = 0.47 Log P_ow + 1.09 = 1.89

The different QSAR’s give different outcomes of the Log K_oc. In view of all uncertainties using QSAR, the mean calculated value should be used:

Mean Log K_oc = 1.63 (range 1.16– 1.97, based on the Log P_ow of the major component of the substance), which corresponds with a K_oc of 42..

Validity criteria fulfilled:

not applicable

Conclusions:

Using different QSARs, the mean Log Koc for BMH was calculated to be 1.63 which corresponds with a Koc of 42.

Cross-reference 3

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20.05 - 17.06.1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study has been performed according to OECD guidance and according to GLP principles. Test report is translated from Japanese.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Deviations:

no

Principles of method if other than guideline:

The test was conducted in accordance with the "Method for testing the biodegradability of chemical substances by microorganisms" stipulated in the "Testing methid for new chemical substances" (1974, Kanpogyo No.5, Planning and Coordination Bureau, Environment Agency, Yakuhatu No. 615, Pharmaceutical Affairs Bureau, Ministry of Health and Welfare, and 49 Kikyoku No. 392, Basic Industries Bureau, Ministry of International Trade and Industry, Japan). This test method equal to the OECD Guideline 301C (Modified MITI Test (I)).

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: standard activated sludge was purchased from the Chemical Biotesting Center, Chemicals Inspection & Testing Institute, Japan
- Method of cultivation: About 1 liter of activated sludge was aerated in the cultivation tank for 23.5 hrs. After stopping aeration for 30 min, about 1/3 of whole ammount was excluded. An equivalent volume of 0.1% sunthetic sewage was added to the excluded supernatant in the tank. The procedure was repeated once every day. Cultivation temp. was 25C.
- Preparation of inoculum for exposure: activated sludge (2.4 mL) was inoculted into each test bottle to make a concentration 30 ppm (w/v)
- Initial cell/biomass concentration:
- Water filtered: pure water

Duration of test (contact time):

28 d

Initial conc.:

100 other: ppm (w/v)

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Test temperature: 25C
- pH: 7.7
- pH adjusted: no
- Aeration of dilution water: no
- Suspended solids concentration: 30 ppm, (v/w)
- Continuous darkness: yes/no


TEST SYSTEM
- Culturing apparatus: test bottles
- Number of culture flasks/concentration: 3 flasks; controls: 1 flask
- Measuring equipment: Coulometer and Quantity of Oxygen Consumption
- test carried in closed system


SAMPLING
- Sampling frequency: BOD checked weekly
after the termination of the test, resudual ammount of the test substance was analysed by HPLC.

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

29.7

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance): 15.9 % degradation after 7 d 25.8 % degradation after 14 d 29.7 % degradation after 28 d

Results with reference substance:

Points of degradation plot (reference substance):
66.4 % degradation after 7 d
72 % degradation after 14 d
73.1 % degradation after 28 d

The percent of biodegradation of BMH calculated by biochemical BOD was 29.7% and by HPLC 99.3%.

According to sponsor's data BMH hydrolyses to HNH - at the end of the test the HPLC measurement confirmed a new peak (retention time 4.2 min) which can be assigned to HNH.

The measurement of HNH (average value 19.2 mg) was in accordance with a theoretical calculation (21.3 mg) of HNH yield from BMH.

At the end of the test, NHN remained in the test solution, but MIBK (another degradation product) failed to be found in the test solution by GC analysis. The results show that BMH was hydrolyses into two substances: HNH and MIBK, but only MIBK was biodegradable.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The test substance is not readily biodegradable under conditions applied in the modified MITI (I) test.

Cross-reference 4

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

N/A

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The biodegradation in water of the hydrolysis product is predicted with BIOWIN (version 4.10), part of EPI Suite. This model is considered reliable by OECD.

Qualifier:

no guideline followed

Principles of method if other than guideline:

BIOWIN estimates the probability of rapid aerobic and anaerobic biodegradation of an organic compound in the presence of mixed populations of environmental microorganisms.  BIOWIN contains seven separate models.  This version (v4.10) designates the models as follows (see also Boethling et al. 2003):
Biowin1  =  linear probability model
Biowin2 =  nonlinear probability model
Biowin3  =  expert survey ultimate biodegradation model
Biowin4  =  expert survey primary biodegradation model
Biowin5  =  MITI linear model
Biowin6  =  MITI nonlinear model
Biowin7  =  anaerobic biodegradation model
Biodegradability estimates are based upon fragment constants that were developed using multiple linear or non-linear regression analyses, depending on the model.

Experimental biodegradation data for Biowin1 and 2 were obtained from Syracuse Research Corporation's (SRC) database of evaluated biodegradation data (Howard et. al. 1987).  This database, and Biowin 1 and 2, are intended to convey a general indication of biodegradability under aerobic conditions, and not for any particular medium.  Biowin3 and 4 yield estimates for the time required to achieve complete ultimate and primary biodegradation in a typical or "evaluative" aquatic environment. Biowin5 and 6 are predictive models for assessing a compound’s biodegradability in the Japanese MITI (Ministry of International Trade and Industry) ready biodegradation test; i.e. OECD 301C.  These models use an approach similar to that used to develop Biowin1 and 2. Biowin7, the anaerobic biodegradation model, is the most recent.  As for the other Biowin models, multiple (linear) regression against molecular fragments was used to develop the model, which predicts probability of rapid degradation in the "serum bottle" anaerobic biodegradation screening test.  This endpoint is assumed to be predictive of degradation in a typical anaerobic digester.

BIOWIN requires only a chemical structure to make these predictions.  Structures are entered into BIOWIN by SMILES (Simplified Molecular Information and Line Entry System) notations.  The BIOWIN program was developed at Syracuse Research Corporation.  The prediction methodology was developed jointly by efforts of the Syracuse Research Corporation and the U.S. Environmental Protection Agency. The following abstract from Boethling et al. (1994), which describes the development of Biowin1-4, briefly summarizes the methodology.  The same basic methodology applies to all seven Biowin models.

"Two independent training sets were used to develop four mathematical models for predicting aerobic biodegradability from chemical structure.  All four of the models are based on multiple regressions against counts of 36 preselected chemical substructures plus molecular weight.  Two of the models, based on linear and nonlinear regressions, calculate the probability of rapid biodegradation and can be used to classify compounds as rapidly or not rapidly biodegradable.  The training set for these models consisted of qualitative summary evaluations of all available experimental data on biodegradability for 295 compounds.  The other two models allow semi-quantitative prediction of primary and ultimate biodegradation rates using multiple linear regression.  The training set for these models consisted of estimates of primary and ultimate biodegradation rates for 200 compounds, gathered in a survey of 17 biodegradation experts.  The two probability models correctly classified 90% of the compounds in their training set, whereas the two survey models calculated biodegradation rates for the survey compounds with R2 = 0.7.  These four models are intended for use in chemical screening and in setting priorities for further review.

GLP compliance:

no

Remarks on result:

other: Predictions with BIOWIN (version 4.10) show that the hydrolysis product MIBK is readily biodegradable; Biowin2 (Non-Linear Model Prediction): Biodegrades Fast (probability: 0.76); Biowin3 (Ultimate Biodegradation Timeframe): Weeks (value: 2.96)

Details on results:

- Ready Biodegradability Prediction: YES
- For detailed results, see section any other information on results incl. tables

--------------------------- BIOWIN v4.10 Results ----------------------------

  Biowin1 (Linear Model Prediction)   : Biodegrades Fast

  Biowin2 (Non-Linear Model Prediction): Biodegrades Fast

  Biowin3 (Ultimate Biodegradation Timeframe): Weeks

  Biowin4 (Primary Biodegradation Timeframe): Days-Weeks

  Biowin5 (MITI Linear Model Prediction)   : Biodegrades Fast

  Biowin6 (MITI Non-Linear Model Prediction): Biodegrades Fast

  Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast

  Ready Biodegradability Prediction: YES

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin1 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | 0.0068 | 0.0068

 MolWt| * | Molecular Weight Parameter                              |        | -0.0477

 Const| * | Equation Constant                                               |        | 0.7475

============+============================================+=========+=========

  RESULT  |   Biowin1 (Linear Biodeg Probability)            |        | 0.7067

============+============================================+=========+=========

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin2 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | -0.4530 | -0.4530

 MolWt| * | Molecular Weight Parameter                                     |        | -1.4223

============+============================================+=========+=========

  RESULT  | Biowin2 (Non-Linear Biodeg Probability)  |        | 0.7565

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Biodegrades Fast

 A Probability Less Than 0.5 indicates --> Does NOT Biodegrade Fast

 

------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin3 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | -0.0225 | -0.0225

 MolWt| * | Molecular Weight Parameter                                     |        | -0.2213

 Const| * | Equation Constant                                                      |        | 3.1992

============+============================================+=========+=========

  RESULT  | Biowin3 (Survey Model - Ultimate Biodeg) |        | 2.9553

============+============================================+=========+=========

 

------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin4 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | -0.0222 | -0.0222

 MolWt| * | Molecular Weight Parameter                       |        | -0.1445

 Const| * | Equation Constant                                               |        | 3.8477

============+============================================+=========+=========

  RESULT  |  Biowin4 (Survey Model - Primary Biodeg) |        | 3.6810

============+============================================+=========+=========

  Result Classification:  5.00 -> hours    4.00 -> days   3.00 -> weeks

 (Primary & Ultimate)   2.00 -> months   1.00 -> longer

 

------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin5 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | 0.1177 | 0.1177

 Frag | 3 | Methyl [-CH3]                                                         | 0.0004 | 0.0012

 Frag | 1 | -CH2- [linear]                                                        | 0.0494 | 0.0494

 Frag | 1 | -CH-  [linear]                                                          | -0.0507 | -0.0507

 MolWt| * | Molecular Weight Parameter                                     |        | -0.2980

 Const| * | Equation Constant                                                      |        | 0.7121

============+============================================+=========+=========

  RESULT  | Biowin5 (MITI Linear Biodeg Probability)               |        | 0.5319

============+============================================+=========+=========

 

------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin6 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                         | 0.8334 | 0.8334

 Frag | 3 | Methyl [-CH3]                                                         | 0.0194 | 0.0583

 Frag | 1 | -CH2- [linear]                                                        | 0.4295 | 0.4295

 Frag | 1 | -CH-  [linear]                                                          | -0.0998 | -0.0998

 MolWt| * | Molecular Weight Parameter                                     |        | -2.8916

============+============================================+=========+=========

  RESULT  |Biowin6 (MITI Non-Linear Biodeg Probability)|        | 0.7017

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Readily Degradable

 A Probability Less Than 0.5 indicates --> NOT Readily Degradable

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin7 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Ketone  [-C-C(=O)-C-]                                      | -0.3919 | -0.3919

 Frag | 3 | Methyl [-CH3]                                                         | -0.0796 | -0.2387

 Frag | 1 | -CH2- [linear]                                                        | 0.0260 | 0.0260

 Frag | 1 | -CH-  [linear]                                                          | -0.1659 | -0.1659

 Const| * | Equation Constant                                                      |        | 0.8361

============+============================================+=========+=========

  RESULT  |  Biowin7 (Anaerobic Linear Biodeg Prob)  |        | 0.0656

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Biodegrades Fast

 A Probability Less Than 0.5 indicates --> Does NOT Biodegrade Fast

 

Ready Biodegradability Prediction: (YES or NO)

----------------------------------------------

 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.

Interpretation of results:

other: not potentially persistent according to the screening criteria

Conclusions:

In water, BMH hydrolyses into two compounds, being 3-Hydroxy-2 -naphthoic acid, hydrazine (HNH; CAS no. 5341-58-2) and Methyl isobutyl ketone (MIBK; CAS no. 108-10-1), with a DT50 of 28 hours under environmentally relevant conditions. The biodegradation in water of MIBK has been predicted with the BIOWIN program (version 4.10). Based on the results from the predictions with Biowin 2 and Biowin 3, MIBK is not potentially persistent according to the screening criteria.

Cross-reference 5

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

N/A

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The biodegradation in water of the hydrolysis product is predicted with BIOWIN (version 4.10), part of EPI Suite. This model is considered reliable by OECD.

Qualifier:

no guideline followed

Principles of method if other than guideline:

BIOWIN estimates the probability of rapid aerobic and anaerobic biodegradation of an organic compound in the presence of mixed populations of environmental microorganisms.  BIOWIN contains seven separate models.  This version (v4.10) designates the models as follows (see also Boethling et al. 2003):
Biowin1  =  linear probability model
Biowin2 =  nonlinear probability model
Biowin3  =  expert survey ultimate biodegradation model
Biowin4  =  expert survey primary biodegradation model
Biowin5  =  MITI linear model
Biowin6  =  MITI nonlinear model
Biowin7  =  anaerobic biodegradation model
Biodegradability estimates are based upon fragment constants that were developed using multiple linear or non-linear regression analyses, depending on the model.

Experimental biodegradation data for Biowin1 and 2 were obtained from Syracuse Research Corporation's (SRC) database of evaluated biodegradation data (Howard et. al. 1987).  This database, and Biowin 1 and 2, are intended to convey a general indication of biodegradability under aerobic conditions, and not for any particular medium.  Biowin3 and 4 yield estimates for the time required to achieve complete ultimate and primary biodegradation in a typical or "evaluative" aquatic environment. Biowin5 and 6 are predictive models for assessing a compound’s biodegradability in the Japanese MITI (Ministry of International Trade and Industry) ready biodegradation test; i.e. OECD 301C.  These models use an approach similar to that used to develop Biowin1 and 2. Biowin7, the anaerobic biodegradation model, is the most recent.  As for the other Biowin models, multiple (linear) regression against molecular fragments was used to develop the model, which predicts probability of rapid degradation in the "serum bottle" anaerobic biodegradation screening test.  This endpoint is assumed to be predictive of degradation in a typical anaerobic digester.

BIOWIN requires only a chemical structure to make these predictions.  Structures are entered into BIOWIN by SMILES (Simplified Molecular Information and Line Entry System) notations.  The BIOWIN program was developed at Syracuse Research Corporation.  The prediction methodology was developed jointly by efforts of the Syracuse Research Corporation and the U.S. Environmental Protection Agency. The following abstract from Boethling et al. (1994), which describes the development of Biowin1-4, briefly summarizes the methodology.  The same basic methodology applies to all seven Biowin models.

"Two independent training sets were used to develop four mathematical models for predicting aerobic biodegradability from chemical structure.  All four of the models are based on multiple regressions against counts of 36 preselected chemical substructures plus molecular weight.  Two of the models, based on linear and nonlinear regressions, calculate the probability of rapid biodegradation and can be used to classify compounds as rapidly or not rapidly biodegradable.  The training set for these models consisted of qualitative summary evaluations of all available experimental data on biodegradability for 295 compounds.  The other two models allow semi-quantitative prediction of primary and ultimate biodegradation rates using multiple linear regression.  The training set for these models consisted of estimates of primary and ultimate biodegradation rates for 200 compounds, gathered in a survey of 17 biodegradation experts.  The two probability models correctly classified 90% of the compounds in their training set, whereas the two survey models calculated biodegradation rates for the survey compounds with R2 = 0.7.  These four models are intended for use in chemical screening and in setting priorities for further review.

GLP compliance:

no

Remarks on result:

other: Biowin2 (Non-Linear Model Prediction): Biodegrades Fast (probability: 0.74); Biowin3 (Ultimate Biodegradation Timeframe): Weeks (value: 2.8)

Details on results:

- For detailed results, see section any other information on results incl. tables

--------------------------- BIOWIN v4.10 Results ----------------------------

  Biowin1 (Linear Model Prediction)   : Biodegrades Fast

  Biowin2 (Non-Linear Model Prediction): Biodegrades Fast

  Biowin3 (Ultimate Biodegradation Timeframe): Weeks

  Biowin4 (Primary Biodegradation Timeframe): Days-Weeks

  Biowin5 (MITI Linear Model Prediction)   : Does Not Biodegrade Fast

  Biowin6 (MITI Non-Linear Model Prediction): Does Not Biodegrade Fast

  Biowin7 (Anaerobic Model Prediction): Does Not Biodegrade Fast

  Ready Biodegradability Prediction: NO

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin1 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                       | 0.1158 | 0.1158

 MolWt| * | Molecular Weight Parameter                        |        | -0.0963

 Const| * | Equation Constant                                               |        | 0.7475

============+============================================+=========+=========

  RESULT  |   Biowin1(Linear Biodeg Probability)             |        | 0.7671

============+============================================+=========+=========

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin2 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                         | 0.9086 | 0.9086

 MolWt| * | Molecular Weight Parameter                         |             | -2.8714

============+============================================+=========+=========

  RESULT  | Biowin2(Non-Linear Biodeg Probability)   |              | 0.7400

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Biodegrades Fast

 A Probability Less Than 0.5 indicates --> Does NOT Biodegrade Fast

 

------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin3 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                        | 0.0564 | 0.0564

 MolWt| * | Molecular Weight Parameter                         |        | -0.4469

 Const| * | Equation Constant                                               |        | 3.1992

============+============================================+=========+=========

  RESULT  | Biowin3(Survey Model - Ultimate Biodeg) |        | 2.8087

============+============================================+=========+=========

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin4 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                         | 0.0397 | 0.0397

 MolWt| * | Molecular Weight Parameter                       |        | -0.2917

 Const| * | Equation Constant                                                 |        | 3.8477

============+============================================+=========+=========

  RESULT  |  Biowin4(Survey Model - Primary Biodeg) |        | 3.5957

============+============================================+=========+=========

  Result Classification:  5.00 -> hours    4.00 -> days   3.00 -> weeks

 (Primary & Ultimate)   2.00 -> months   1.00 -> longer

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin5 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                       | 0.0642 | 0.0642

 Frag | 6 | Aromatic-H                                                 | 0.0082 | 0.0493

 Frag | 1 | Hydrazine [-N-NH-]                                                | -0.3730 | -0.3730

 MolWt| * | Molecular Weight Parameter                          |        | -0.6016

 Const| * | Equation Constant                                               |        | 0.7121

============+============================================+=========+=========

  RESULT  | Biowin5(MITI Linear Biodeg Probability) |        |-0.1489

============+============================================+=========+=========

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin6 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                       | 0.4884 | 0.4884

 Frag | 6 | Aromatic-H                                                | 0.1201 | 0.7208

 Frag | 1 | Hydrazine [-N-NH-]                                              |-14.6593 |-14.6593

 MolWt| * | Molecular Weight Parameter                           |        | -5.8377

============+============================================+=========+=========

  RESULT  |Biowin6(MITI Non-Linear Biodeg Probability)|        | 0.0000

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Readily Degradable

 A Probability Less Than 0.5 indicates --> NOT Readily Degradable

 ------+-----+--------------------------------------------+---------+---------

 TYPE | NUM |      Biowin7 FRAGMENT DESCRIPTION        | COEFF | VALUE 

------+-----+--------------------------------------------+---------+---------

 Frag | 1 | Aromatic alcohol [-OH]                                       | 0.0807 | 0.0807

 Frag | 6 | Aromatic-H                                                | -0.0954 | -0.5726

 Frag | 1 | Hydrazine [-N-NH-]                                                | 0.0000 | 0.0000

 Const| * | Equation Constant                                               |        | 0.8361

============+============================================+=========+=========

  RESULT  |  Biowin7(Anaerobic Linear Biodeg Prob)  |        | 0.3442

============+============================================+=========+=========

  A Probability Greater Than or Equal to 0.5 indicates --> Biodegrades Fast

 A Probability Less Than 0.5 indicates --> Does NOT Biodegrade Fast

 

Ready Biodegradability Prediction: (YES or NO)

----------------------------------------------

 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.

 

 

Validity criteria fulfilled:

not applicable

Interpretation of results:

other: not potentially persistent according to the screening criteria

Conclusions:

In water, BMH hydrolyses into two compounds, being 3-Hydroxy-2 -naphthoic acid, hydrazine (HNH; CAS no. 5341-58-2) and Methyl isobutyl ketone (MIBK; CAS no. 108-10-1), with a DT50 of 28 hours under environmentally relevant conditions. The biodegradation in water of HNH has been predicted with the BIOWIN program (version 4.10). Based on the results from the predictions with Biowin 2 and Biowin 3, HNH is not potentially persistent according to the screening criteria.

Cross-reference 6

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

N/A

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The partition coefficient of the hydrolysis product is calculated with KOWWIN (version 1.67), part of EPI Suite. This model is considered reliable by OECD.

Qualifier:

no guideline followed

Principles of method if other than guideline:

KOWWIN (the Log Octanol-Water Partition Coefficient Program) estimates the logarithmic octanol-water partition coefficient (log P) of organic compounds. KOWWIN requires only a chemical structure to estimate a log P. Structures are entered into KOWWIN by SMILES (Simplified Molecular Input Line Entry System) notations.

The KOWWIN program and estimation methodology were developed at Syracuse Research Corporation.

KOWWIN uses a "fragment constant" methodology to predict log P. In a "fragment constant" method, a structure is divided into fragments (atom or larger functional groups) and coefficient values of each fragment or group are summed together to yield the log P estimate. KOWWIN’s methodology is known as an Atom/Fragment Contribution (AFC) method. Coefficients for individual fragments and groups were derived by multiple regression of 2447 reliably measured log P values. KOWWIN’s "reductionist" fragment constant methodology (i.e. derivation via multiple regression) differs from the "constructionist" fragment constant methodology of Hansch and Leo (1979) that is available in the CLOGP Program (Daylight, 1995). See the Meylan and Howard (1995) journal article for a more complete description of KOWWIN’s methodology.

The KOWWIN training and validation datasets can be downloaded from the Internet at:
http://esc.syrres.com/interkow/KowwinData.htm

References:
Hansch, C and Leo, A.J. 1979. Substituent Constants for Correlation Analysis in Chemistry and Biology; Wiley: New York, 1979.
Daylight. 1995. CLOGP Program. Daylight Chemical Information Systems. Von Karman Ave., Irvine, CA 92715. (web-site as of March 2008: http://www.daylight.com/)
Meylan, W.M. and P.H. Howard. 1995. Atom/fragment contribution method for estimating octanol-water partition coefficients. J. Pharm. Sci. 84: 83-92.

GLP compliance:

no

Type of method:

other: QSAR (KOWWIN, version 1.67)

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

1.16

Temp.:

25 °C

Remarks on result:

other: Substance: MIBK (hydrolysis product)

TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION          | COEFF | VALUE

-------+-----+--------------------------------------------+---------+--------

 Frag | 3 | -CH3   [aliphatic carbon]                                                     | 0.5473 | 1.6419

 Frag | 1 | -CH2-  [aliphatic carbon]                                                    | 0.4911 | 0.4911

 Frag | 1 | -CH    [aliphatic carbon]                                                      | 0.3614 | 0.3614

 Frag | 1 | -C(=O)- [carbonyl, aliphatic attach]                                  |-1.5586 | -1.5586

 Const |    | Equation Constant                                                                  |        | 0.2290

-------+-----+--------------------------------------------+---------+--------

                                                        Log Kow  =  1.1648

Conclusions:

In water, BMH hydrolyses into two compounds, being 3-Hydroxy-2 -naphthoic acid, hydrazine (HNH; CAS no. 5341-58-2) and Methyl isobutyl ketone (MIBK; CAS no. 108-10-1), with a DT50 of 28 hours under environmentally relevant conditions (see IUCLID 5.1.2). The Kow of MIBK has been calculated with the KOWWIN program (version 1.67). The Log Kow is calculated to be 1.16

Cross-reference 7

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

N/A

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The partition coefficient of the hydrolysis product is calculated with KOWWIN (version 1.67), part of EPI Suite. This model is considered reliable by OECD.

Qualifier:

no guideline followed

Principles of method if other than guideline:

KOWWIN (the Log Octanol-Water Partition Coefficient Program) estimates the logarithmic octanol-water partition coefficient (log P) of organic compounds. KOWWIN requires only a chemical structure to estimate a log P. Structures are entered into KOWWIN by SMILES (Simplified Molecular Input Line Entry System) notations.

The KOWWIN program and estimation methodology were developed at Syracuse Research Corporation.

KOWWIN uses a "fragment constant" methodology to predict log P. In a "fragment constant" method, a structure is divided into fragments (atom or larger functional groups) and coefficient values of each fragment or group are summed together to yield the log P estimate. KOWWIN’s methodology is known as an Atom/Fragment Contribution (AFC) method. Coefficients for individual fragments and groups were derived by multiple regression of 2447 reliably measured log P values. KOWWIN’s "reductionist" fragment constant methodology (i.e. derivation via multiple regression) differs from the "constructionist" fragment constant methodology of Hansch and Leo (1979) that is available in the CLOGP Program (Daylight, 1995). See the Meylan and Howard (1995) journal article for a more complete description of KOWWIN’s methodology.

The KOWWIN training and validation datasets can be downloaded from the Internet at:
http://esc.syrres.com/interkow/KowwinData.htm

References:
Hansch, C and Leo, A.J. 1979. Substituent Constants for Correlation Analysis in Chemistry and Biology; Wiley: New York, 1979.
Daylight. 1995. CLOGP Program. Daylight Chemical Information Systems. Von Karman Ave., Irvine, CA 92715. (web-site as of March 2008: http://www.daylight.com/)
Meylan, W.M. and P.H. Howard. 1995. Atom/fragment contribution method for estimating octanol-water partition coefficients. J. Pharm. Sci. 84: 83-92.

GLP compliance:

no

Type of method:

other: QSAR (KOWWIN, version 1.67)

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

1.85

Temp.:

25 °C

Remarks on result:

other: Substance: HNH (hydrolysis product)

TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION                 | COEFF | VALUE

-------+-----+--------------------------------------------+---------+--------

 Frag | 1 | -NH2   [aliphatic attach]                                                      |-1.4148 | -1.4148

 Frag | 1 | -NH-   [aliphatic attach]                                                       |-1.4962 | -1.4962

 Frag | 10 | Aromatic Carbon                                                                   | 0.2940 | 2.9400

 Frag | 1 | -OH    [hydroxy, aromatic attach]                                    |-0.4802 | -0.4802

 Frag | 1 | -C(=O)N [aromatic attach]                                                 | 0.1599 | 0.1599

 Factor| 1 | -NH-NH- structure correction                                       | 1.1330 | 1.1330

 Factor| 1 | Ortho-Hydroxy to misc. -C(=O)- correction                              | 0.7770 | 0.7770

 Const |    | Equation Constant                                                                      |        | 0.2290

-------+-----+--------------------------------------------+---------+--------

                                                        Log Kow  =  1.8477

Conclusions:

In water, BMH hydrolyses into two compounds, being 3-Hydroxy-2 -naphthoic acid, hydrazine (HNH; CAS no. 5341-58-2) and Methyl isobutyl ketone (MIBK; CAS no. 108-10-1), with a DT50 of 28 hours under environmentally relevant conditions. The Kow of HNH has been calculated with the KOWWIN program (version 1.67). The Log Kow is calculated to be 1.85.

Cross-reference 8

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 November 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: Directive 92/69/EEC, A.8 (HPLC method) (EEC publ.no L383, Dec 1992)

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Version / remarks:

(1989)

GLP compliance:

yes

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

1.7

Temp.:

20 °C

pH:

6

Remarks on result:

other: major component

Type:

log Pow

Partition coefficient:

0.6

Temp.:

20 °C

pH:

6

Remarks on result:

other: minor component

Details on results:

estimated log Pow based on Rekker Calculation method: 3.76
estimated pKa based on Perrin's Calculation method: acidic groups (phenol) 8.38, basic groups (ARCONHR) -1.92

Two peaks were observed in the chromatogram and it was assumed that the large peak derives from the major component of BMH whereas the small peak derives from a minor component in BMH. All test substance related peaks eluted well within 10 minutes.

The results of the Calculation method and the HPLC method are not in agreement. Since the HPLC method is a more accurate method than the Calculation method, the result of the HPLC method is reported as the partition coefficient (n-octanol/water), Pow, of BMH.

The t₀ (the retention time of the unretarded component) was determined to be 0.866 minutes as a mean value of both measurements (i.e. 0.866 and 0.866 minutes).

Substance	tr^1	k’	log k’	log Pow	Pow
Reference substance
Ethylmethylketone	1.307	0.509	-0.293	0.3
Nitrobenzene	2.074	1.395	0.145	1.9
Toluene	3.453	2.987	0.475	2.7
Bromobenzene	3.792	3.378	0.529	3.0
1,4-dichlorobenzene	4.934	4.697	0.672	3.4
Biphenyl	5.781	5.676	0.754	4.0
Test substance
minor component	1.410	0.628	-0.202	0.6^2	3.9
major component	2.010	1.320	0.121	1.7^2	48

¹      Mean value of the retention times of two chromatograms.

²      Interpolated from the regression line: log k’ = 0.297*log P_ow- 0.378 (r=0.994, n = 6)

Conclusions:

The HPLC method (with UV-detection) was used to determine the n-octanol/water partition coefficient of BMH. At 20.0 +/- 0.5°C , the Pow value for the major component in BMH is 48 (log Pow = 1.7) and for the minor component in BMH the Pow is 3.9 (log Pow = 0.6).

Cross-reference 9

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27-29 November 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

Directive 92/69/EEC, A.4 (static technique) (EEC publ no. L383, Dec 1992)

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

(1995)

GLP compliance:

yes

Type of method:

static method

Test no.:

#1

Temp.:

37.55 °C

Vapour pressure:

2.77 Pa

Remarks on result:

other: First vapour pressure

Test no.:

#2

Temp.:

31.18 °C

Vapour pressure:

1.33 Pa

Remarks on result:

other: Second vapour pressure

Test no.:

#3

Temp.:

24.21 °C

Vapour pressure:

0.56 Pa

Remarks on result:

other: third vapour pressure

Key result

Temp.:

20 °C

Vapour pressure:

0.33 Pa

Remarks on result:

other: Estimated vapour pressure value at 20°C using the least squares method.

At the beginning of the test, the vapour pressure of the test substance decreased slightly every next measurement, due to the removal of volatile impurities. After measurement 17 this decrease became negligible and the vapour pressure was stable. So from that moment on, the collected data were used for the final result.

Measurement	Temperature [°C]	mean vapour pressure [Pa]
18 -27	37.55	2.77 +/- 0.15
30 -37	31.18	1.33 +/- 0.03
40 -52	24.21	0.56 +/- 0.01

The experimenatlly determined vapour pressure values were plotted against the reciprocal temperature [T-¹] (in Kelvin; see attached background information), taking into account the calculated error.

Fitting these data using a least squares method gives a value of 0.326 Pa with 0.017 Pa for 2s_n-1(i.e. 2.5%) for the vapour pressure of the test substance at 20°C. The maximum deviation between the fit and the data points is always less than about 2%. Errors made in estimating the mean value per temperature series are up to 5.2%. So a value of 0.02 Pa (i.e. 6.1%) is a reasonable value for the uncertainty in the final result.

Conclusions:

The vapour pressure of BMH was determined using the static method at 20°C and was found to be: p (20°C) = 0.33 ± 0.02 Pa = (2.4 ± 0.2) x 10-3 mm Hg.

Cross-reference 10

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 November - 5 December 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: Directive 92/69/EEC, A.6 (column elution method) (EEC publ. no L383, Dec 1992)

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

(1995)

GLP compliance:

yes

Type of method:

column elution method

Key result

Water solubility:

4.37 mg/L

Temp.:

20 °C

pH:

8.4

Details on results:

Preliminary test:
- concentration in water sample after 3 times centrifugation: 0.178 mg/l
- extra peak observed in HPLC-UV at approximately 3.5 minutes -> most likely originating from a (soluble) impurity in BMH

Main test:
- no test substance related response observed in the chromatogram of samples from the 'blank' columns
- concentrations in samples taken at flow rate 24 ml/h: mean value column 1: 4.15 mg/L, mean value column 2: 4.13 mg/L
- concentrations in samples taken at flow rate 12 ml/h: mean value column 1: 4.64 mg/L, mean value column 2: 4.55 mg/L
- overall mean (both columns and both flow-rates): 4.37 mg/L

- extra peak observed in HPLC-UV of all loaded carrier material column samples at approximately 3.5 minutes -> most likely originating from a (soluble) impurity in BMH (the lower the flow rate the higher the response)
- pH in pooled water samples varied between 8.3 and 8.5

Conclusions:

Interpretation of results: slightly soluble (0.1-100 mg/L)
The column elution method was used to determine the water solubility of BMH at 20.0 ± 0.5°C as 4.37x10^-3 g/L.

Data source

Reference

Reference Type:

other company data

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Argumentation is provided for 'study scientifically not necessary / other information available', based on available physico-chemical, fate and ecotoxicological properties information and in agreement with column 2 of Regulation (EC) No 1907/2006 Annex IX section 9.4. Effects on terrestrial organsims.

GLP compliance:

no

Test material

Test material information

Constituent 1

Details on test material:

- Name of test material (as cited in study report): BMH
- Substance type: white crystal
- Physical state: solid
- Analytical purity: 99.8%
- Lot/batch No.: OG76
- Expiration date of the lot/batch: 05 December 2001
- Stability under test conditions: stability in water: no;
- Stability under storage conditions: stable
- Storage condition of test material: In the refrigerator, in the dark

Sampling and analysis

Analytical monitoring:

not required

Test substrate

Details on preparation and application of test substrate:

not applicable - no test performed

Test organisms

Test organisms (inoculum):

soil

Study design

Remarks:

statement based on available physico-chemical, fate and ecotoxicological property information

Test conditions

Details on test conditions:

not applicable - no test performed

Results and discussion

Effect concentrations

Key result

Remarks on result:

not measured/tested

Details on results:

The biodegradation in water of HNH and MIBK has been predicted with the Biowin program (version 4.10). Based on the results from the predictions with Biowin 2 and Biowin 3, HNH and MIBK are not potentially persistent according to the screening criteria. The logPOW values of BMH and the hydrolysis products are low ( logPOW : 1.16 to1.85) and thus they do not have a high potential to adsorb to soil. The latter is confirmed through the low calculated KOC values based on the experimentally determined log POW values. Taking into account that BMH is partially ionized under environmental relevant conditions, high potential to absorb to soil is unlikely. Based on rapid hydrolysis of BMH into two non- persistent hydrolysis products and low potential for adsorption of all three substances, they are not deemed to be persistent into the soil compartment.
Based on the activated sludge respiration inhibition test, the substance was concluded to show no toxicity towards activated sludge microorganisms at a concentration of 100 mg/L, it is most likely that also soil microorganisms will not be inhibited by the substance.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

Taking into account the available information of the substance with regard to environmental relevance and exposure of the soil compartment, it is considered scientifically justified to waive testing of this substance for toxicity to soil microorganisms.