1,4-bis[(2-ethyl-6-methylphenyl)amino]anthraquinone

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

bioaccumulation in aquatic species, other

Remarks:

(Q)SAR calculated endpoint

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2022

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 adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
Estimation Programme Interface (EPI) Suite programme for Microsoft Windows v4.11.


2. MODEL (incl. version number)
BCFBAF v3.01


3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
SMILES: CCc1cccc(C)c1Nc2ccc(Nc3c(C)cccc3CC)c4C(=O)c5ccccc5C(=O)c24


4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
Please refer to attached justification.


5. APPLICABILITY DOMAIN
Please refer to attached justification.


6. ADEQUACY OF THE RESULT
Please refer to attached justification.

Qualifier:

according to guideline

Guideline:

other: ECHA's Guidance on information requirements and chemical safety assessment Chapter R.6: QSARs and grouping of chemicals

Principles of method if other than guideline:

The prediction of BCF for the registered substance was performed using the model BCFBAF v.3.01 (November 2012).

- Software tool(s) used including version:
Estimation Programme Interface (EPI) Suite programme for Microsoft Windows v4.11.

- Model(s) used:
BCFBAF v3.01

GLP compliance:

no

Remarks:

not relevant

Specific details on test material used for the study:

SMILES: (C)c1Nc2ccc(Nc3c(C)cccc3CC)c4C(=O)c5ccccc5C(=O)c24
logKow=8.6

Type:

BCF

Value:

568.7 L/kg

Remarks on result:

other: EPI Suite v4.11 model with BCFBAF v3.01

Conclusions:

BCFBAF predicts a logBCF value of 2.75 (BCF =569 L/kg) for the registered substance.

Executive summary:

The bioconcentration factor (BCF) of the registered substance was estimated using the BCFBAF v3.01 QSAR model available from the US EPA. The estimated bioconcentration factor of the registered substance is 569 L/kg.

 

Reference 2

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with criteria fulfilled for an aqueous exposure: Use of solubilizer at low concentration (0.2 µg/l)/ Test technically feasible with aqueous phase but dietary exposure may be more relevant

Qualifier:

according to guideline

Guideline:

other: Test Method Relating to New Chemical Substances (Kanpogyo No.5, Yakuhatsu No.615, 49 Kikyoku No.392, 1974, amended 1998)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 305 (Bioconcentration: Flow-through Fish Test)

Deviations:

no

GLP compliance:

yes

Radiolabelling:

no

Vehicle:

yes

Details on preparation of test solutions, spiked fish food or sediment:

Dissolving assisstant in test water: HCO-30 8 µg/mL
If possible no solubilizer should be applied to the test system. But as the results for the BCF are very small and the usage of a solubilizer is increasing the concentration of the test substance in the test system, the present result can be used as a worst case displaying a very low bioaccumulation potential for the substance.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

Species:
- Source: Sankyo Suisan, 1-1, Ichigayatamachi, Shinjuku-ku, Tokyo, Japan
- Date of purchase: July 25, 1997
- Lot number: 97-K-0725
- Total length: approx. 10 cm
- Body weight: 20-40 g
- Fat content: 4.4%

Acclimation:
- Aquarium number: B-5
- Water temperature.: 25 +/- 2 °C
- Period: >= 1 weeks
- Food: Hikari Staple Mini from Kyorin
- Feeding: The food was given in an amount of approx. 2% of the fish weight everyday except weekends and holidays
- Mortality during the 1 week before testing: 0%

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

4 wk

Hardness:

No data

Test temperature:

23.8-24.2°C

pH:

No data

Dissolved oxygen:

5.2-8.3 mg/l

TOC:

No data

Salinity:

n.a.

Details on test conditions:

The bioconcentration test system was set up in duplicate. One group of carp was set as the control, another group was exposed to the test substance. During the exposure period, the concentrations of the test substance in water and fish were measured periodically. The bioconcentration factors (BCF) calculated from the results were used to evaluate the bioaccumulative potential of the test substance in tissues of carp.

Test Conditions:
- Exposure Ievel (nominal concentration of the test substance): Exposure Ievel: 0.2 µg/mL (HC0-30, 8 µg/mL), Control: 0 µg/mL (HC0-30, 8 µg/mL)
- Supply of dilution water: 800 L/day (Turnover rate: 20 times/day)
- Supply of feed solution: 20 ml/day
- Number of fish (at the beginning of the exposure period): 12 fish in 40-L test water (Exposure Ievel), 10 fish in 40-L test water (Control)

Preparation of feed solutions:
- Feed solution for exposure Ievel: 8.0 mg/mL test substance , 320 mg/mL HC0-30
- Feed solution for control: 320 mg/mL HC0-30
- The feed solutions were renewed within approx. 2 weeks

Stability of feed solution:
- On day 18 after the preparation, the test substance was detected 100% (7766 µg/mL) of the initial concentration (7732 µg/mL) by HPLC, indicating that the test substance was sufficiently stable in the feed solution.

Preparation of test water:
- Each feed solution was supplied to a mixing glass tube with a metering pump for the feed solution, diluted to the respective nominal concentration by mixing with dilution water delivered through a metering pump for dilution water, and then supplied to each lest chamber.

Stability of test solution:
- On day 2 after preparation, the test substance was detected 99% (9.6 µg/mL) of the initial concentration (9.7 µg/mL), indicating that the test substance was sufficiently stable in test water.

Stability in water:
- On day 2 after preparation, the test substance was detected 99% (9.6 µg/ml) of the initial concentration (9.7 µg/ml), indicating that the test substance was sufficiently stable in test water.

Dispersibility of the test substance
- A portion of the water dispersion noted above was passed through a membrane filter having a pore size of 0.45 µm. The pre- and post-filtered water dispersions were analyzed with HPLC. The examination showed that 100% of the test substance had particle sizes of less than 0.45 µm. The dispersibility of the test substance in water was thus shown to be satisfactory.

During the exposure period, the test system was controlled as follows:
- Feeding: Hikari Staple Mini from Kyorin was given in an amount of approx. 2.5% of the fish weight everyday except weekends and holidays.
- Conditions of fish: Observation were made on the external appearance of fish and the swimming andfeeding behavior.
- Dissolved oxygen and temperature: The dissolved oxygen (DO) and temperature were measured twice a week.
- Fat content: The fat content of 4 control fish sampled at middle of the exposure period was measured.

Measurement of test substance:
- Test water was analyzed twice a week periodically. On weeks 1, 2 and 4 of the exposure period, three fish were taken from the exposure chamber and two of them were analyzed.

Nominal and measured concentrations:

The bioconcentration test was accordingly conducted at the exposure Ievel, 0.2 µg/mL, lower than a hundredth of the 48-hour LC50 (85 µg/ml).The mean concentration of the test substance during the exposure period was 0.225 µg/ml and sufficiently close to the nominal values of 0.2 µg/ml. The coefficients of variation for concentration were 2.4%.

Reference substance (positive control):

no

Details on estimation of bioconcentration:

After the test the exposed fishes were cut into pieces with scissors and homogenized for 5 min. at approx. 10,000 rpm. After several filter and homogenization steps the eluate is applied to HPLC. The control fishes that were not exposed to the test substance were used as a blank test and were analyzed equally.

Calculation of bioconcentration factor:
- The bioconcentration factor (BCF) was calculated by the following equation: BCF = (Cf-Cfo) / Cw
where Cf : Concentration in fish (µg/g)
Cfo : Concentration in control fish (µg/g) based on the result of fish blank test, Cfo was treated equal to 0
Cw : Mean concentration in water (µg/mL)

Limit of determination of bioconcentration factor
- The lowest detectable amount of test substance in fish was 0.25 µg/g, indicating that bioconcentration factor can be obtained when the test substance is concentrated by factors of 1 (These factors depend on the fish weight used for an analysis).

Type:

BCF

Value:

2 - 5 dimensionless

Basis:

whole body w.w.

Remarks on result:

other: The concentration of the test substance in fish ranged from 0.37 to 1.08 µg/g (w/w).

Remarks:

Conc.in environment / dose:0.2 µg/ml

Details on results:

No mortality was observed during the exposure period of 4 weeks. Therefore, it was confirmed that the test fish had been reared appropriately:
- Condition of fish: There was no abnormality in shape of the body or in swimming and feeding behavior
- Body weight: 21.32-29.41 g
- Total length: 9.5-10.6 cm
- Fat content: 4.4% (n=4, 4.0-4.9%)

Validity criteria fulfilled:

yes

Conclusions:

The concentration of the test substance in fish ranged from 0.37 to 1.08 µg/g (w/w) and the bioconcentration (BCF) was 2 to 5. On the basis of the BCF obtained, it is concluded that the bioaccumulation potential of the test substance in fish is low under the test condition.

Executive summary:

The simplified study for 4 weeks with one exposure level was conducted in reference to the Test Method Relating to New Chemical Substauces (Kanpogyo No.5, Yakuhatsu No.615, 49 Kikyoku No.392, 1974, amended I 998), which is equivalent to the OECD Guideline 305. The bioconcentration test system was set up in duplicate. One group of carp was set as the control, another group was exposed to the test substance (using HCO-30 as a solubilizer in the test medium). During the exposure period, the concentrations of the test substance in water and fish were measured periodically. The bioconcentration factors (BCF) calculated from the results were used to evaluate the bioaccumulative potential of the test substance in tissues of carp. Prior to the bioconcentration test, an acute toxicity test was conducted with Medaka and 50% lethal concentration (LC5O) was determined, using HCO-30 as a solubilizer in the test system. The bioconcentration test was carried out at the exposure level not exceeding a hundredth of the 48hour LC50 (85 µg/ml). The concentration of the test substance in fish ranged from 0.37 to 1.08 µg/g (w/w) and the bioconcentration (BCF) was 2 to 5.

Description of key information

Reinblau RLW, Key, Rel 2,Test Method Relating to New Chemical Substances (Kanpogyo No.5, Yakuhatsu No.615, 49 Kikyoku No.392, 1974, amended 1998)/similar to OECD 305; Mitsubishi, 2011: BCF=2-5 

Key value for chemical safety assessment

BCF (aquatic species):

5 dimensionless

Additional information

Additional information: 

The concentration of the test substance in fish ranged from 0.37 to 1.08 µg/g (w/w) and the bioconcentration (BCF) was 2 to 5 (Mitsubishi, 2011). On the basis of the BCF obtained, it is concluded that the bioaccumulation potential of the test substance in fish is low under the test condition.

As the test substance has a very low water solubility HCO-30 was used as solubilizer in the test system. If possible no solubilizer should be applied to the test system. But as the results for the BCF are very small and the usage of a solubilizer is increasing the concentration of the test substance in the test system, the present result can be used as a worst case displaying a very low bioaccumulation potential for the substance under environmentally relevant conditions.

Category approach:

A category approach has been defined (see attached justification document in section 13). The category consists of substances all having the diamino-anthraquinone structure as a common moiety which is linked to phenyl groups via the amino groups. Differences within the category are described by various alkyl groups bound to the phenyl groups. All substances included in the category approach are poorly water soluble with high adsorption coefficient (log Koc>6), high partition coefficient (logKow>8) and not readily biodegradable.

Data available on other members of the category confirmed the low bioaccumulation of the substances:

Reinblau BLW (CAS n°32724-62-2)	QSAR (EPI) Suite V4.11 - BCFBAF v3.01	BCF= 4.76 L/kg
Green 3 (CAS n°128-80-3)	QSAR (EPI) Suite V4.11 - BCFBAF v3.01	BCF=893 L/kg
Violet 36 (CAS n° 82-16-6)	QSAR (EPI) Suite V4.11- BCFBAF v3.01	BCF=798 L/kg
Green 28 (CAS n° 4851-50-7)	QSAR (EPI) Suite V4.11- BCFBAF v3.01	BCF=53 L/kg
Blue 104 (CAS n°116-75-6)	QSAR (EPI) Suite V4.11- BCFBAF v3.01	BCF=405.4 L/kg