Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Several in vivo tests with a 40-50% solution of tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate ("PBTCNa4") in rabbits are available. The test solution was applied on the inner surface on rabbit ears. In these tests PBTCNa4 was not irritating.
In a further test the test item was classified as irritant, based on the content of phosphonic acids > 10%.
Aditionally for the evaluation of the skin corrosion/irritating properties of PBTCNa4 an artificial 3D-skin model test according to OECD TG 431/439 was used.
Two in vivo assay in rabbits equivalent or similar to OECD TG 405 are available. In these assays a 40-50% solution of PBTCNa4 in water was used. Additionally an in vitro study for assessing ocular irritation of compounds using a human epithelial corneal cell model was conducted.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin corrosion: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
other: OECD TG 431
Qualifier:
according to guideline
Guideline:
EU Method B.40 (In Vitro Skin Corrosion: Transcutaneous Electrical Resistance Test (TER))
Principles of method if other than guideline:
The experiment was carried out on a reconstructed human epidermis EST-1000 (CeIiSystems, St. Katharinen, Germany).
GLP compliance:
yes
Test system:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Source species:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Cell type:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Cell source:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Source strain:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Vehicle:
unchanged (no vehicle)
Amount/concentration applied:
Application of the test material and incubation
For testing of chemical induced corrosivity the EST-1000 inserts were exposed to 25 mg of the test item (plus 50µl 0.9% NaCl to moisten and ensure good contact with the skin) for 3min. (RT) and 60 min. in the incubator (3 inserts per period of incubation time), respectively. 0.9% NaCl (50µl) treated epidermal models were used as negative controls (determination in triplicates).
Duration of treatment / exposure:
Application of the test material and incubation
For testing of chemical induced corrosivity the EST-1000 inserts were exposed to 25 mg of the test item (plus 50µl 0.9% NaCl to moisten and ensure good contact with the skin) for 3min. (RT) and 60 min. in the incubator (3 inserts per period of incubation time), respectively. 0.9% NaCl (50µl) treated epidermal models were used as negative controls (determination in triplicates).
Species:
other: not applicable - in-vitro 3D skin corrosion test
Strain:
other: not applicable - in-vitro 3D skin corrosion test
Type of coverage:
other: not applicable - in-vitro 3D skin corrosion test
Preparation of test site:
other: not applicable - in-vitro 3D skin corrosion test
Vehicle:
other: not applicable - in-vitro 3D skin corrosion test
Controls:
other: not applicable - in-vitro 3D skin corrosion test
Duration of treatment / exposure:
After an exposure period of 3 or 60 minutes, followed by a post-treatment incubation period of about 3 hours, the cell viability was measured
Observation period:
not applicable - in-vitro 3D skin corrosion test
Number of animals:
not applicable - in-vitro 3D skin corrosion test
Details on study design:
Determination of cell viability (MTT)
After the incubation period the inserts were washed carefully in PBS and MTT reduction was performed. For viability testing the inserts were placed in new 24 well plates containing 300 µl of MTT solution (37°C, 1mg/ml in MTT-assay medium, delivered by Cell Systems®). The tissues were incubated for about 3 hours under cell culture conditions (5% C 2, 37°C, max humidity). The extraction of blue formazan was performed in Isopropanol (24 weil plates, 2ml/insert) on a vertical shaker (at least 60 min.). For determination of cell viability the absorption of the Isopropanol extracts were measured in duplicates at 570 nm in an automatie reader (EL808, BioTek; 96 well format, 200 µl).
Irritation / corrosion parameter:
other: cell viability
Run / experiment:
mean
Value:
105.05
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: 3 min
Remarks:
score = 105.05; max. score =100, non corrosive - scores in {%] viability
Irritation / corrosion parameter:
other: cell viability
Run / experiment:
mean
Value:
106.25
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: 60 min
Remarks:
score = 106.25; max score = 100, non corrosive - scores in [%] viability

Compound       [%] Cell viability 3 min       [%] Cell viability 60 min      Classification*

Bayhibit S                   105.05                                    106.25             Non-corrosive                   

Negative control          100.00                                    100.00              Negative control

*: Classification was done in accordance with the existing guideline and

internationally accepted protocols, i.e. evaluation of LD50 values after 3 min. and/or less than 15% viability after a 60 min. incubation period.

Interpretation of results:
GHS criteria not met
Conclusions:
The results show that no corrosive property of the test item was determined by the assay used.
Executive summary:

The experiment was carried out on a reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany) for detection of topically applied skin corrosives with the test item tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate.

Corrosive skin effects of substances are defined as irreversible damage of skin; namely, visible necrosis through the epidermis and into the dermis, following the application of a test substance for up to four hours. In vivo corrosive reactions are typified by ulcers, bleeding, and bloody scabs.

A 100% concentration was tested on the skin/epidermal equivalents in triplets. For the determination of time related cytotoxic effects the incubation periods were 3 min. and 60 min., respectively. By this the study, was conducted in accordance with the OECD 431 guideline as well as with an EC guideline (amending Council Directive 67/548/EEC, B.40 Skin corrosion) using the test item concentrations and incubation periods recommended there. These tests are also related to the revised OECD 404 guideline "Acute Dermal Irritation/Corrosion".

To check the reliability of this test procedure a blinded positive/negative control study is conducted at regular intervals in the lab. This reliability check is always performed by two technicians, two laboratories in parallel using the same batches of the control test items.

The test item was applied at a 100% concentration, i.e. 25 mg per insert. (plus 50 µl 0.9% NaCl to moisten and ensure good contact with the skin)

The MTT (Methylthiazoletetrazolium) method has determined the following values of viability after 3 min. or after 60 min. of incubation: 105% and 106% (rounded), respectively. Thus, the results show that no corrosive property of the test item was determined by the assay used.

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
other: OECD TG 439
Qualifier:
according to guideline
Guideline:
other: EU method B.46
Principles of method if other than guideline:
The experiment was carried out on a reconstructed human epidermis EST-1000 (CeIiSystems, St. Katharinen, Germany)
GLP compliance:
yes
Test system:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Source species:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Cell type:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Cell source:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Source strain:
other: Reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
Vehicle:
unchanged (no vehicle)
Details on test system:
The experiment was carried out on a reconstructed human epidermis EST-1000 (CellSystems, St. Katharinen, Germany).
The tissue equivalents were shipped in 24 well cell culture plates on Agarose supplemented with maintenance medium (Kit contents EST-1000; CellSystems, Cat.-No.CS-1001). Inserts were of 0.6 cm2 size. All tests were performed in triplets.
Species:
other: not applicable - in-vitro 3D skin irritation test
Strain:
other: not applicable - in-vitro 3D skin irritation test
Type of coverage:
other: not applicable - in-vitro 3D skin irritation test
Preparation of test site:
other: not applicable - in-vitro 3D skin irritation test
Vehicle:
other: not applicable - in-vitro 3D skin irritation test
Controls:
other: not applicable - in-vitro 3D skin irritation test
Duration of treatment / exposure:
After an exposure period of 20 minutes, followed by a 42 hours post-treatment incubation period, the cell viability was measured
Observation period:
not applicable - in-vitro 3D skin irritation test
Number of animals:
not applicable - in-vitro 3D skin irritation test
Details on study design:
Adaptation to cell culture conditions
Inserts with EST-1000 reconstructed human epidermis (0.6 cm²) were packed under sterile conditions and were shipped refrigerated on supplemented Agarose. Upon arrival, 6 well culture plates were pre-filled with 1ml of fresh and cool maintenance medium. The reconstructed tissues were placed into the prepared cell culture plates (1 insert/well) and were adapted to the recommended tissue culture conditions (5% CO2, 37°C, max humidity) afterwards for at least 6 hours before use. In case of cultivation of the skin equivalents for more than 24 hours, a daily medium change is required by aspirating the medium and replacing it by 1ml new maintenance medium (37°C) for each well.
Irritation / corrosion parameter:
other: other: cell viability
Value:
101.56
Remarks on result:
other:
Remarks:
Basis: mean. Time point: ca. 42 hours. Max. score: 100.0. Reversibility: other: not applicable - in-vitro 3D skin irritation test. Remarks: non-irritant - scores in [%] viability. (migrated information)

Compound              Cell viability [%]        Classification*

Test item                    101.56                Non Irritant (NI)

Positive control                1.50                  Irritant (I)

Negative control           100.00                 Non irritant (NI)

*: Classification was done in accordance with EU Test Method B.46

In vitro result                      In vivo prediction

mean tissue viabilit < 50        Irritant (I)

mean tissue viability > 50      Non-irritant (NI)

(I): Irritant , R38 = Skin irritation category 2, H315

(NI): Non – irritant = no skin irritation category

Interpretation of results:
GHS criteria not met
Conclusions:
The results show that no skin irritant property of tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was determined by the assay used.
Executive summary:

The experiment was carried out according to EU Test Method B.46 using commercially available reconstructed human epidermis (RHS) model EST-1000 (CellSystems, St. Katharinen, Germany).

Undiluted tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was applied topically to the RHS model, i.e. 30 mg per insert (plus 30 µl 0.9% NaCl to moisten and ensure good contact with the skin; three replicates).

After an exposure period of 20 minutes, followed by a 42 hours post-treatment incubation period, the cell viability was measured to be 102 % (rounded) in the MTT (Methylthiazoletetrazolium) conversion assay.

The results of the concurrent negative control (NC, 0.9% NaCl) and positive control (PC, 5% SDS) demonstrated the viability (NC) and sensitivity (PC) of the test model.

Thus, the results show that no skin irritant property of tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was determined by the assay used.

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
Not indicated.
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: An 41.4 % aqueous solution of the test substance was used
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
yes
Remarks:
, see below
Qualifier:
according to guideline
Guideline:
other: EG-guideline 83/467
Principles of method if other than guideline:
1- 7 days observations and scoring instead of 14 days.

GLP compliance:
not specified
Species:
rabbit
Strain:
not specified
Details on test animals or test system and environmental conditions:
- Diet: rabbit food 222 from the company Hönig ad libitum
- Water: ad libitum
- Weight at study initiation: 2.5 - 4kg
- both sexes
Type of coverage:
occlusive
Preparation of test site:
other: The test area was selected intentionally to be the hairless inner part of the ear.
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
0.5 mL of the undiluted test substance.
Duration of treatment / exposure:
24 hours.
Observation period:
7 days.
Number of animals:
2 rabbits.
Details on study design:
TEST SITE
- Area of exposure: The hairless inner side of the ear
- Type of wrap if used: A small cellulose tissue with the undiluted test substance was attached with plasters to the inner side of the rabbit's ear. For better support a rolled piece of cellulose was attached to the ear.
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
other: 24 h, 2nd day, 6th d and 7th d
Score:
0
Max. score:
4
Reversibility:
other: not applicable - score = 0 at any time point
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
other: 24h, 2nd day, 6th d, 7th d
Score:
0
Max. score:
4
Reversibility:
other: not applicable - score = 0 at any time point
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
edema score
Basis:
animal #1
Time point:
other: 24 h,2nd day, 6th d, 7th d
Score:
0
Max. score:
4
Reversibility:
other: not applicable - score = 0 at any time point
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
edema score
Basis:
animal #2
Time point:
other: 24h, 2nd day, 6th d, 7th d
Score:
0
Max. score:
4
Reversibility:
other: not applicable - score = 0 at any time point
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
erythema score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
fully reversible
Irritation parameter:
edema score
Basis:
mean
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
fully reversible
Irritant / corrosive response data:
Not observed (score of 0)
Other effects:
No other effects.

No remarks.

Interpretation of results:
GHS criteria not met
Conclusions:
According to the present study the test substance is not a skin irritant.
Executive summary:

The test substance, tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate, was tested for skin irritation effects in two rabbits. The test substance was applied on the inner part of the rabbit's ear for 24 hours. During the 7 days of observation no pathological signs appeared (edema, erythema, corrosion) in the tested area (score 0). It is therefore concluded that under the test conditions the test substance does not induce skin irritation effects.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Referenceopen allclose all

Endpoint:
eye irritation: in vitro / ex vivo
Remarks:
artificial human 3D-Cornea model
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study
Principles of method if other than guideline:
In vitro study for assessing ocular irritation of compounds using a human epithelial corneal cell model. The model used is standardized and commercially available (SkinEthic™ Human Corneal Epithelial Model (HCE); SkinEthic, France).
GLP compliance:
yes
Species:
other: not applicable - human corneal epithelial model (HCE)
Strain:
other: not applicable - human corneal epithelial model (HCE)
Vehicle:
other: not applicable - human corneal epithelial model (HCE)
Controls:
other: not applicable - human corneal epithelial model (HCE)
Duration of treatment / exposure:
After an exposure period of 60 minutes, followed by a 16 hours post-treatment incubation period, the cell viability was measured
Observation period (in vivo):
not applicable - human corneal epithelial model (HCE)
Number of animals or in vitro replicates:
not applicable - human corneal epithelial model (HCE)
Irritation parameter:
in vitro irritation score
Remarks:
Cell viability
Run / experiment:
mean value
Value:
84.62
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
no indication of irritation

A test substance is predicted to be an ocular irritant if the mean relative tissue viability (%) exposed to the test substance is <50%.

As can be seen from the information in the Table below the test substance tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was not detected as positive in this test model.

Compound                     Cell viability [%]       Evaluation

Test item                          84.62                non-irritant

Positive control                     26.83                   irritant

Negative control               100.00               non-irritant

Interpretation of results:
GHS criteria not met
Executive summary:

This in vitro study for assessing ocular irritation of compounds using a human epithelial corneal cell model was performed in 2012. The model used is standardized and commercially available (SkinEthicTM Human Corneal Epithelial Model (HCE); SkinEthic, France).

Undiluted tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was applied topically to the HCE tissue, i.e. 30 mg per insert (plus 30 µl PBS to moisten and ensure good contact with the skin; three replicates).

After an exposure period of 60 minutes, followed by a 16 hours post-treatment incubation period, the cell viability was 85% (rounded) as measured by a MTT conversion assay.

The results of the concurrent negative (NC, PBS) and positive control (PC, 1H-1,2,4-Triazole-3-thiol) demonstrated the viability (NC) and sensitivity (PC) of the test model.

The results show that tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate is predicted as non-irritant under the conditions of this test method.

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
Not indicated.
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: an 41.4% aqueous solution of the test substance was used
Qualifier:
according to guideline
Guideline:
other: EG-guideline 83/467
Deviations:
not specified
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
yes
Remarks:
, see below
Principles of method if other than guideline:
- A score for the 72 hour observation is missing.
- No mean calculations of the scores were performed for grading.
GLP compliance:
not specified
Species:
rabbit
Strain:
not specified
Details on test animals or tissues and environmental conditions:
- Diet (e.g. ad libitum): rabbit food 222 from the company Hönig with libitum.
- Water (e.g. ad libitum): Water with libitum.
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
0.1 mL of the undiluted test substance.
Duration of treatment / exposure:
Single application. No rinsing after application.
Observation period (in vivo):
7 days.
Number of animals or in vitro replicates:
2 rabbits.
Details on study design:
The effects of the test substance according to the parameters mentioned below were examined 1 hour and 24 hours after application of the substance and in the 3rd, 6th and 7th day.
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
other: 1, 24 hours, 3rd, 6th, 7th day
Score:
0
Max. score:
4
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
iris score
Basis:
animal #1
Time point:
other: 1, 24 hours, 3rd, 6th, 7th day
Score:
0
Max. score:
2
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #1
Time point:
other: 1 hour
Score:
2
Max. score:
3
Reversibility:
fully reversible within: <= 6 days
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #1
Time point:
other: 24 hours, 3rd day
Score:
1
Max. score:
3
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #1
Time point:
other: 6th, 7th day
Score:
0
Max. score:
3
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
other: 1, 24 hours, 3rd, 6th, 7th day
Score:
0
Max. score:
4
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
other: 1, 24 hours, 3rd, 6th, 7th day
Score:
0
Max. score:
4
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
iris score
Basis:
animal #2
Time point:
other: 1, 24 hours, 3rd, 6th, 7th day
Score:
0
Max. score:
2
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #2
Time point:
other: 1 hour
Score:
2
Max. score:
3
Reversibility:
fully reversible within: <= 6 days
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #2
Time point:
other: 24 hours, 3rd day
Score:
1
Max. score:
3
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
other: Erythema score
Basis:
animal #2
Time point:
other: 6th, 7th day
Score:
0
Max. score:
3
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
other: 1, 24 hours; 3rd day
Score:
1
Max. score:
4
Reversibility:
fully reversible within: <= 6 days
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
other: 6th, 7th day
Score:
0
Max. score:
4
Remarks on result:
other: 41.4% test substance in water
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
24 h
Score:
0
Max. score:
4
Reversibility:
other: score = 0 at any time point
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
48 h
Remarks on result:
not measured/tested
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
72 h
Score:
0
Max. score:
4
Reversibility:
other: score = 0 at any time point
Irritation parameter:
iris score
Basis:
mean
Time point:
24 h
Score:
0
Max. score:
2
Reversibility:
other: score = 0 at any time point
Irritation parameter:
iris score
Basis:
mean
Time point:
48 h
Remarks on result:
not measured/tested
Irritation parameter:
iris score
Basis:
mean
Time point:
72 h
Score:
0
Max. score:
2
Reversibility:
other: score = 0 at any time point
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
24 h
Score:
1
Max. score:
3
Reversibility:
fully reversible within: 6 days
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
48 h
Remarks on result:
not measured/tested
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
72 h
Score:
1
Max. score:
3
Reversibility:
fully reversible within: 6 days
Irritation parameter:
chemosis score
Basis:
mean
Time point:
24 h
Score:
ca. 0.5
Max. score:
4
Reversibility:
fully reversible within: 6 days
Irritation parameter:
chemosis score
Basis:
mean
Time point:
48 h
Remarks on result:
not measured/tested
Irritation parameter:
chemosis score
Basis:
mean
Time point:
72 h
Score:
ca. 0.5
Max. score:
4
Reversibility:
fully reversible within: 6 days
Irritant / corrosive response data:
Slightly irritating reversible effects were observed: Redness and swelling of the eyes (the conjumctivae tissue). No corrosive response was observed.
The study concludes a light eye irritating effect by the highest score for each parameter for the two rabbits examined.
Other effects:
No other effects.

No remarks.

Interpretation of results:
GHS criteria not met
Conclusions:
According to the study the test substance can cause light eye irritating effects.
Executive summary:

The test substance tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was tested for mucosa (eye) irritation effects. After application of the test substance in the eyes of two rabbits, their conjunctiva tissue appeared to be slightly red and swelled. These irritation effects were reversible during the time frame of the study. Hence, under study conditions and by the highest score achieved for each parameter the test substance appears to cause a slight eye irritation.

Compared with the current guideline, a score for the 72 hour observation is missing and no mean calculations of the scores were performed for grading.

When the presented study results/scores are evaluated by a calculation of the mean scores of the available data (1h, 24h, 72h), the test substance should thereby be classified as non-irritant.

As the study was reasonably conducted, it is recommended for animal welfare reasons, not to repeat the study.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

In the in-vivo assays tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was not irritating to the eyes and skin of rabbits. This also applies for the in-vitro assays.

For the in vivo tests an aqueous solution was used. Therefore the tests are regarded as supporting studies and in-vitro tests with the water free test substance were conducted.


Justification for selection of skin irritation / corrosion endpoint:
For the evaluation of the skin corrosion/irritating properties of tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate an artificial 3D-skin model was used. Both studies are used for classification to differentiate if the substance is corrosive or irritant.
Additionally the results of in-vivo studies (40-50% solution of the test substance ) were taken into account.

Justification for selection of eye irritation endpoint:
For the evaluation of the eye irritant properties of tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate a test using a human epithelial corneal cell model was used.
Additionally the results of in-vivo studies (40-50% solution of the test substance ) were taken into account.

Justification for classification or non-classification

Tetrasodium hydrogen 2-phosphonatobutane-1,2,4-tricarboxylate was not irritating to the skin and eyes in the in vivo and not irritating/corrosive in the in vitro assays.

According to CLP classification criteria (Regulation (EC) No 1272/2008) a classification is not justified.