Phosphoric acid, butyl ester, branched, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

18 Jul - 10 Aug 2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

no analytical determination was performed

Cross-reference

Reason / purpose for cross-reference:

read-across source

Remarks:

link to target

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

weight of evidence

Study period:

18 Jul - 10 Aug 2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

no analytical determination was performed; read-across

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The present analogue approach contemplates Phosphoric acid, butyl ester, branched, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (CAS 98679-19-7) as target substance for read across from the source substance Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates (CAS 96690-34-5). The read-across approach is used to evaluate the hazardous potential of the target substance with respect to ecotoxicological endpoints and human health for REACH Annex VII.
Based on similar chemical structures, read-across based on different compounds having the same type of effect(s) as described in scenario 2 of the Read-Across Assessment Framework document can be used as a basis for assessment.
The target substance (Phosphoric acid, butyl ester, branched, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine) and the source substance (Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates) are both organic UVCB substances.
In consequence, read-across can be justified due to the high structural similarities as well as common properties, which will be outlined in detail below.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)

Source: Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates (EC 306-227-4, CAS 96690-34-5)
The substance is manufactured from the educts phosphorus pentoxide (CAS 1314-56-3, EC 215-236-1), 2-butanol (CAS 78-92-2, EC 201-158-5), iso-butanol (CAS 78-83-1, EC 201-148-0) and Amines, C12-14-tert-alkyl (CAS 68955-53-3, EC 273-279-1).

Target: Phosphoric acid, butyl ester, branched, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine (EC 308-859-6, CAS 98679-19-7)
The substance is manufactured from the educts phosphor pentoxide (CAS 1314-56-3, EC 215-236-1), 2-butanol (CAS 78-92-2, EC 201-158-5), iso-butanol (CAS 78-83-1, EC 201-148-0) and bis(2-ethylhexyl)amine (CAS 106-20-7, EC 203-372-4)

Both substances do not contain any impurities which may impact the feasibility of read-across.

3. ANALOGUE APPROACH JUSTIFICATION
Both substances are organic UVCBs and are manufactured from the educts phosphorus pentoxide (CAS 1314-56-3, EC 215-236-1), 2-butanol (CAS 78-92-2, EC 201-158-5), iso-butanol (CAS 78-83-1, EC 201-148-0) in similar ratios, the only slight difference is the amine part. In the source chemical, Amines, C12-14-tert-alkyl is used, and in the target bis(2-ethylhexyl)amine.
So, the reaction products have a similar distribution pattern with regard to varied alkyl phosphate species (mainly dialkyl phosphates). Both used amines have similar molecular weights, i.e. 185.35-213.41 g/mol (CAS 68955-53-3) and 241.46 g/mol (CAS 106-20-7), which are hence not expected to alter their toxicokinetic behaviour essentially. The fact that one amine is mono-substituted and the other di-substituted, is also not considered to impact the suitability for read-across, as amines are considered to be rather stable functional groups, e.g. hydrolytically stable, and are not considered to be altered to a relevant extent in the body. Both amines are not covalently bound to the phosphates, so they are expected to dissociate into similar dissociation products, too.
Last but not least, both substances show similar physico-chemical properties. They are both liquid at all relevant handling temperatures, both are characterized by negative glass transition temperatures they do not boil but decompose, have similar densities and low vapour pressures indicating that they are no volatile liquids. They have both logPow values and water solubilities which, despite slight variations, are not expected to alter essentially their uptake and distribution through the body.
As there is not sufficient data on both source and target substance available, and the amine is considered to be the main difference and also not covalently bound to the phosphates, data on human health relevant endpoints is retrieved from publically available data sources, i.e. ACToR (https://actor.epa.gov/actor/searchidentifier.xhtml) and RTECS (http://ccinfoweb.ccohs.ca/rtecs/search.html). Further, ecotoxicological properties were estimated via US EPA EpiSuite ECOSAR Class Program v1.11.
Data indicate that both amines produce severe irritating reactions when applied into the eye or onto the skin. Further, the acute dermal toxicity LD50 values are nearly identical in the rabbit (acute tox. Cat. 4), and when applied orally, the available LD50 values similarly indicate that a classification as acute toxic Cat. 4 is triggered. With regard to ecotoxicological properties, the estimated values slightly differ. However, they consistently trigger the same classification, as both substances are not biodegradable; the source chemical is not, so the same can be applied to the amines.
So in consequence, taking into account the similar manufacturing process, i.e. identical and similar educts, and so similar reaction products, similar physico-chemical properties of the source and target chemical and similar (eco)toxicological properties of the source and target amines, the read-across from Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates to Phosphoric acid, butyl ester, branched, compd. with 2-ethyl-N-(2-ethylhexyl)-1-hexanamine is scientifically justified.

4. DATA MATRIX

Table: Data Matrix, source and target chemical
Endpoint Source: CAS 96690-34-5 Target: CAS 98679-19-7
Physical state at 20°C, 1013 hPa liquid liquid
Glass transition temperature -44.95 °C -72.1 °C (onset)
Decomposition 243.36 °C 167.1°C (onset)
Density 0.97 g/cm³ 0.968 g/cm³
Vapour pressure ≤ 54 Pa at 20°C < 6.7 Pa at 20°C
logPow ≥ 0.69 - ≤ 5.6 (estimated) - 0.61 at 23°C
Water solubility 1322 mg/L at 25 °C and pH 3.57 17.14 g/l at 20°C
Surface tension 42.9 mN/m at 20°C and 0.66g/l 37.8 mN/m ≤ST ≤ 41.2 mN/m at 20°C and 1g/l
Flash point 1 35°C at 101.325 kPa 107.5°C at 101.3 kPa

Table: Data Matrix, source and target amine
Endpoint Source amine: CAS 68955-53-3 Target: CAS 106-20-7
Acute oral toxicity LD50 = 552 mg/kg (m/f mice, 470 - 719 mg/kg) (ACToR) LD50 = 800µL/kg (mouse, intraperitoneal) (ACToR, RTECS)
LD50 = 320 mg/kg (male rats) (ACToR; RTECS) LD50 = 1640mg/kg (rat) (ACToR, RTECS)
LD50 = 300 mg/kg (rat) (RTECS)
Acute dermal toxicity LD50 = 251 mg/kg (m/f rats, 190 - 322 mg/kg) (ACToR) LD50 = 1190uL/kg (rabbit) (ACToR, RTECS)
LD50 = 1.12 g/kg (rabbits, 0.83 - 1.51) (ACToR, RTECS)
Acute toxicity inhalation LC50 = 157 ppm (female rats, 1.19 mg/L; 90 - 249 ppm) (ACToR, RTECS)
LC50 > 231 ppm (male rats, 1.75 mg/L) (ACToR, RTECS) No data
LC50 > 940 mg/m³/4h (rats) (RTECS)
Skin irritation Severe reaction (rabbit, Draize test) (RTECS) Severe reaction (rabbit, Draize test) (RTECS)
Severe reaction (rabbit, open irritation test) (RTECS)
Mild reaction (rabbit, open irritation test) (RTECS)
Eye irritation Severe reaction (rabbit, Draize test) (RTECS) Severe reaction (rabbit, Draize test) (RTECS)
Genetic Toxicity No data Negative ±S9 (Ames test) (ACToR)
Fish 96-hr LC50 0.644 mg/L* 0.047 mg/L*
0.632 mg/L** 0.016 mg/L**
Daphnid 48-hr LC50 0.104 mg/L* 0.010 mg/L*
0.458 mg/L** 0.014 mg/L**
Green Algae 96-hr EC50 0.047 mg/L* 0.003 mg/L*
0.939 mg/L** 0.059 mg/L**
Fish ChV 0.015 mg/L* 0.000546 mg/L*
0.082 mg/L** 0.003 mg/L**
Daphnid ChV 0.012 mg/L* 0.00131 mg/L*
0.088 mg/L** 0.004 mg/L**
Green Algae ChV 0.019 mg/L* 0.00134 mg/L*
0.424 mg/L** 0.039 mg/L**
* Aliphatic Amines
** Neutral Organic SAR (Baseline Toxicity)

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hessisches Ministerium für Umwelt, Energie, Landwirtschaft und Verbraucherschutz

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: a water accommondated fraction was performed: for each test concentration the required amount of test item was dispersed in dilution water and was shaked at 130 rpm for 24 h at room temperature; subsequently the suspensions were filtered through glass fibre filters and eluates were used for the test
- Differential loading: 0.5, 1.0, 2.0, 4.0 and 8.0 mg/L
- Controls: yes

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: STRAUS (clone 5)
- Source: obtained from BASF SE, Limburgerhof, Germany; the strain originated from the Institut National de Recherche Chimique Appliquee, France in 1978 and cultivated since then at BASF using medium M4 acc. Elendt
- Feeding during test: no feeding during the test
- Food type: for cultivation: with Desmodesmus subspicatus- and/or Chlorella sp.cells

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: daphnids are transferred into fresh medium one day before the study start in order to ensure the lest animals were less than 24 hours old.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20.8 -21.1 °C (control)
20.7 - 21.2 °C (test item concentration)

pH:

8.02 - 8.70 (control)
8.03 - 8.92 (test item concentration)

Dissolved oxygen:

8.3 - 8.5 mg O2/L (control)
7.7 - 8.4 mg O2/L (test item concentration)

Nominal and measured concentrations:

control, 0.5, 1.0, 2.0, 4.0, 8.0 loading of the test item (mg/L)

Details on test conditions:

TEST SYSTEM
Test vessel:
- Type: open
- Material, size, headspace, fill volume: 50 ml-glass beakers, 50 ml volume
- No. of organisms per vessel: 5 animals
- No. of vessels per concentration (replicates): 20
- No. of vessels per control (replicates): 20

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: test item was diluted with test water which was prepared according to OECD Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, 2000
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH, temperature and oxygen content was measured at test start and test end

OTHER TEST CONDITIONS
- Photoperiod: light/dark cycle 16h of light and 8 hours of darkness

EFFECT PARAMETERS MEASURED: immobility at 24 and 48 h

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: 5.1, 10.8, and 100 mg/L
- Results used to determine the conditions for the definitive study: Based on the results of the screening /range-finding test (20% inhibition at 5 mg/L and 90% inhibition at 10 mg/L) the concentrations of the main test was performed

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EL10

Effect conc.:

0.56 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.01 - 0.94 mg/L

Duration:

48 h

Dose descriptor:

other: EL20

Effect conc.:

0.72 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.05 - 1.15 mg/L

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

1.13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.44 - 2.54 mg/L

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

0.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Details on results:

- Mortality of control: no mortality was observed
- Others: Biological Results are summarized in the tables 1-3 within the section: "Overall remarks, attachments"

Results with reference substance (positive control):

- ECx: EL50 (24 h) 1.0 mg/L

Reported statistics and error estimates:

The inhibition values as well as the statistical calculation were done according to the guideline using the commercial computer program ToxRat Version 2.10.

Validity criteria fulfilled:

yes

Conclusions:

The substance is considered to be not rapidly degradable in the environment. With an EL50 (48 h) = 1.13 mg/L the substance has to be classified and labelled as “Aquatic Chronic 2” (H411) according to the consolidated version Regulation (EC) No 1272/2008 (CLP) and considering all further amendments. As the EL50 is > 1mg/l, no classification as "Aquatic Acute Cat. 1" is triggered.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hessisches Ministerium für Umwelt, Energie, Landwirtschaft und Verbraucherschutz

Test material

Test material information

Constituent 1

Reference substance name:

Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates

EC Number:

306-227-4

EC Name:

Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates

Cas Number:

96690-34-5

Molecular formula:

C4H11O4P to C8H20O7P2 as representative molecular formula of the composition as specified in section 1.2

IUPAC Name:

Amines, C12-14-tert-alkyl, mixed sec-Bu and iso-Bu phosphates

Specific details on test material used for the study:

Physical state at 20°C, 1013 hPa: liquid
Glass transition temperature: -44.95 °C
Decomposition: 243.36 °C
Density: 0.97 g/cm³
Vapour pressure: ≤ 54 Pa at 20°C
log Pow: ≥ 0.69 - ≤ 5.6 (estimated)
Water solubility: 1322 mg/L at 25 °C and pH 3.57
Surface tension: 42.9 mN/m at 20°C and 0.66g/l
Flash point: 135°C

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: a water accommondated fraction was performed: for each test concentration the required amount of test item was dispersed in dilution water and was shaked at 130 rpm for 24 h at room temperature; subsequently the suspensions were filtered through glass fibre filters and eluates were used for the test
- Differential loading: 0.5, 1.0, 2.0, 4.0 and 8.0 mg/L
- Controls: yes

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: STRAUS (clone 5)
- Source: obtained from BASF SE, Limburgerhof, Germany; the strain originated from the Institut National de Recherche Chimique Appliquee, France in 1978 and cultivated since then at BASF using medium M4 acc. Elendt
- Feeding during test: no feeding during the test
- Food type: for cultivation: with Desmodesmus subspicatus- and/or Chlorella sp.cells

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: daphnids are transferred into fresh medium one day before the study start in order to ensure the lest animals were less than 24 hours old.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

20.8 -21.1 °C (control)
20.7 - 21.2 °C (test item concentration)

pH:

8.02 - 8.70 (control)
8.03 - 8.92 (test item concentration)

Dissolved oxygen:

8.3 - 8.5 mg O2/L (control)
7.7 - 8.4 mg O2/L (test item concentration)

Nominal and measured concentrations:

control, 0.5, 1.0, 2.0, 4.0, 8.0 loading of the test item (mg/L)

Details on test conditions:

TEST SYSTEM
Test vessel:
- Type: open
- Material, size, headspace, fill volume: 50 ml-glass beakers, 50 ml volume
- No. of organisms per vessel: 5 animals
- No. of vessels per concentration (replicates): 20
- No. of vessels per control (replicates): 20

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: test item was diluted with test water which was prepared according to OECD Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures, 2000
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH, temperature and oxygen content was measured at test start and test end

OTHER TEST CONDITIONS
- Photoperiod: light/dark cycle 16h of light and 8 hours of darkness

EFFECT PARAMETERS MEASURED: immobility at 24 and 48 h

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
- Test concentrations: 5.1, 10.8, and 100 mg/L
- Results used to determine the conditions for the definitive study: Based on the results of the screening /range-finding test (20% inhibition at 5 mg/L and 90% inhibition at 10 mg/L) the concentrations of the main test was performed

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EL10

Effect conc.:

0.56 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.01 - 0.94 mg/L

Effect concentrations 2

Duration:

48 h

Dose descriptor:

other: EL20

Effect conc.:

0.72 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.05 - 1.15 mg/L

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

1.13 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Remarks on result:

other: 95% confidential limits

Remarks:

0.44 - 2.54 mg/L

Effect concentrations 4

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

0.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Effect concentrations 5

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Details on results:

- Mortality of control: no mortality was observed
- Others: Biological Results are summarized in the tables 1-3 within the section: "Overall remarks, attachments"

Results with reference substance (positive control):

- ECx: EL50 (24 h) 1.0 mg/L

Reported statistics and error estimates:

The inhibition values as well as the statistical calculation were done according to the guideline using the commercial computer program ToxRat Version 2.10.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The substance is considered to be not rapidly degradable in the environment. With an EL50 (48 h) = 1.13 mg/L the substance has to be classified and labelled as “Aquatic Chronic 2” (H411) according to the consolidated version Regulation (EC) No 1272/2008 (CLP) and considering all further amendments. As the EL50 is > 1mg/l, no classification as "Aquatic Acute Cat. 1" is triggered.