Disodium 4,4'-bis[[6-anilino-4-[(2-hydroxyethyl)methylamino]-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulphonate

Endpoint summary

Description of key information

Rat oral LD50 > 10000 mg/kg bw

Rat inhalation LC50 > 1895 mg/m3

Rat dermal LD50 > 2000 mg/kg bw

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedures are well documented and scientifically acceptable.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Principles of method if other than guideline:

The acute oral LD50 of the test substance in rats of both sexes was tested administrating the test item by gavage at doses of 6000, 7750 and 10000 mg/kg bw; the animals were observed over a period of 14 days.

GLP compliance:

not specified

Remarks:

Pre GLP.

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

other: Tif RAIf

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: testing laboratory.
- Weight at study initiation: 160 to 180 grams.
- Fasting period before study: animal fasted overnight.
- Housing: housed in group of 5 in Macrolon cages (type 3).
- Diet: ad libitum, rat food NAFAG, Gossau SG.
- Water: ad libitum.
- Acclimation period: for a minimum of 4 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 1 °C
- Humidity: 55 ± 5 %
- Photoperiod: 14 hrs light cycle day.

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 2 %
- Preparation of the solution: the suspension was homogeneously dispersed with Ultra-Turrax and during it was kept stable with magnetic stirred.

Doses:

6000, 7750, 10000 mg/kg bw

No. of animals per sex per dose:

5 males and 5 females per dose.

Details on study design:

- Duration of observation period following administration: 14 days
- Necropsy of survivors performed: yes

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 10 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths occurred.

Clinical signs:

Within 2 hours after treatment the rats in all dosage groups showed sedation, dyspnoea, curved position and ruffled fur. The animals recovered within 8 days.

Gross pathology:

No substance related gross organ changes were seen.

Rate of deaths

Dose mag/kg	Conc. % of formulation	N. of animals		Died within
				1 h		24 hrs		48 hrs		7 days		14 days
		F	M	F	M	F	M	F	M	F	M	F	M
6000	50	5	5	0	0	0	0	0	0	0	0	0	0
7750	50	5	5	0	0	0	0	0	0	0	0	0	0
10000	50	5	5	0	0	0	0	0	0	0	0	0	0

Interpretation of results:

not classified

Remarks:

Migrated information according to the CLP Regulation Criteria used for interpretation of results: EU

Conclusions:

LD50 > 10000 mg/kg bw

Executive summary:

Method

The acute oral LD50 of the substance in rats of both sexes was tested administrating the test item by gavage at doses of 6000, 7750 and 10000 mg/kg bw; the animals were observed over a period of 14 days.

Results

No deaths occurred. Within 2 hours after treatment the rats in all dosage groups showed sedation, dyspnoea, curved position and ruffled fur. The animals recovered within 8 days.

LD50 > 10000 mg/kg bw

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

10 000 mg/kg bw

Quality of whole database:

The study is supported by many other studies on the substance and in agreement with the results for all category members (see Category Justification Report in section 13). Substance purity > 80 %.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

other: read-across based on grouping of substances (category approch)

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Particle size not specified. Justification for Read Across is reported in the endpoint summary and in the Category Justification Report attached to the Section 13 of this dossier.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

no

Remarks:

Pre GLP.

Test type:

standard acute method

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen, Germany.
- Weight at study initiation: 180 - 200 g.

Route of administration:

inhalation: dust

Type of inhalation exposure:

not specified

Vehicle:

air

Analytical verification of test atmosphere concentrations:

yes

Remarks:

gravimetric with membrane filter.

Duration of exposure:

1 - 4 h

Concentrations:

163.3, 375, 1225 and 1895 mg/m³ air at 4 hour exposure.
1820 mg/m³ air at 1 hour exposure.

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days .
- Necropsy of survivors performed: yes.
- Other examinations performed: clinical signs.

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 1 895 mg/m³ air (nominal)

Based on:

test mat.

Exp. duration:

4 h

Sex:

male/female

Dose descriptor:

LC50

Effect level:

1 820 mg/m³ air (nominal)

Based on:

test mat.

Exp. duration:

1 h

Mortality:

No mortality occuerred.

Clinical signs:

other:

Gross pathology:

No abnormalities detected.

Interpretation of results:

other: not applicable.

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

LC50 (4 h): > 1.895 mg/l air

Executive summary:

Method

Acute inhalation toxicity was assessed following the method described into the OECD guideline 403.

Results

LC50 (4 h): > 1.895 mg/l air

LC50 (1 h): 1.820 mg/l air

Conclusion

According to the CLP Regulation (EC 1272/2008), 3.1 Acute toxicity section, substances can be allocated to one of four toxicity categories based on acute toxicity by the oral, dermal or inhalation route according to the numeric criteria. Acute toxicity values are expressed as (approximate) LD50 (oral, dermal) or LC50 (inhalation) values or as acute toxicity estimates (ATE).

The inhalation LD50 value classification limit for dust is 5.0 mg/l (category 4: 1.0 < ATE ≤ 5.0 mg/l). In the current test an LD50 was non identified; considering the fact that no mortality occurred, a classification category can not be assigned. Thus, a classification according to the CLP Regulation (EC 1272/2008) is not applicable.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

1 895 mg/m³

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

other: read-across based on grouping of substances (category approch)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted according to internationally accepted testing guidelines and performed according to GLP but used in RA

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL, Biological Research Laboratories Ltd., Wblferstrasse 4, CH-4414 Fullinsdorf.
- Age at study initiation: 10 weeks (males), 12 weeks (females).
- Weight at study initiation: 225 - 247 g (males), 200 - 222 g (females).
- Housing: individually in Makrolon type-2 cages with standard softwood bedding ("Lignocel", Schill AG, CH-4132 Muttenz).
- Diet: pelleted standard Kliba 343, Batches 77/90 and 78/90 rat maintenance diet ("Kliba", Klingentalmuehle AG, CH-4303 Kaiseraugst); ad libitum.
- Water: community tap water from Itingen; ad libitum.
- Acclimation period: one week.

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 3 °C
- Humidity: 40-70 %
- Air changes: 10 - 15 air changes per hr.
- Photoperiod: 12 / 12 hrs dark / hrs light.

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: backs of the animals.
- Preparation: clipping 24 h before application.
- % coverage: 10% of the total body surface.

REMOVAL OF TEST SUBSTANCE
- Washing: with lukewarm tap water.
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount applied: 4 ml
- Concentration: 100%
- For solids, paste formed: yes

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: observations four times during test day 1, and daily during days 2 - 15; weighing on test days 1 (pre-administration), 8 and 15.
- Necropsy of survivors performed: yes
- Other examinations performed: gross pathology.

Statistics:

The LOGIT-Model could not be applied to the observed rate of death. The toxicity was estimated without use of a statistical model.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality.

Clinical signs:

No systemic signs were observed in the animals during the entire observation period.
Skin observations: males/females: scales (back) (10/10); general erythema (back) (3/10); males: erythema focal (back) (3/5). All animals had recovered from the local signs after 7 observation days.

Body weight:

Mean body weight (g): days 1, 8, 15
- males: 236.2, 265.2, 294.8
- females: 207.3, 214.0, 217.8

Gross pathology:

No findings noted.

Interpretation of results:

not classified

Remarks:

Migrated information according to the CLP Regulation Criteria used for interpretation of results: EU

Conclusions:

LD50 > 2000 mg/kg bw

Executive summary:

Method

Upon an acute oral single administration (2000 mg/kg bw) and a 15 day post-treatment observation period, the dermal LD50 was determined for the test substance, according to the OECD guideline 402.

Results

LD50 > 2000 mg/kg bw

No deaths accorred and no systemic signs were observed in the animals during the entire observation period. Skin reactions are all recovered after 7 observation days.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Several acute toxicity studies were performed on the substance under registration. The most reliable was performed with a purity of the test substance > 80 % and resulted in LD50 very high, over 10000 mg/Kg bw. Some studies resulted in a lower LD50 (between 5000 and 10000), but purity was reported as less than 50 % and no information on the other constituents is provided.

In conclusion, an LD50 greater than 10000 mg/Kg bw has been set for the substance under registration.

A valid GLP study for acute dermal toxicity was reported (RCC, Research & Consulting Company AG., 1991), performed just at 2000 mg/Kg bw with no effect. The tested substance is the analogous 3a-MSA, the dihydoxyethyl derivative tetrasulphonated, belonging to the Stilbene Fluorescent Whitening Agents category, group 3. It has similar organic functional groups, while the sulphonation degree is higher than that of 3b-A, therefore 3a-MSA has also higher salification degree.

Skin adsorption was evaluated and calculated for all members of the category (see Category Justification Report, Section 13 of the dossier).

As it can be noted, the influence of the variability in functional group is very low, more related to the variability in the polarity of the substance than on potential reactivity that can arise a concern. From a metabolic point of view, estimation with OECD Toolbox of the dermal metabolism was performed in order to verify if breakdown products may be formed. Results are negative for all members. Oral acute toxicity is also comparable for the two substances, with very high estimated LD50. The two substances are expected to have a similar behaviour regarding dermal acute toxicity, as well as all the other members of the Stilbene Fluorescent Whitening Agents category.

Because of the physical state and the trade forms, inhalation is not an appropriate route of exposure. Acute toxicity results for the other two exposure routes indicate no concern therefore no testing was performed. One test is available on an analogous substance, performed at the maximum allowed concentration of 1890 mg/m3: no effects were observed. The analogous substance, part of the Stilbene Fluorescent Whitening Agents, group 3, is the acid form of the disulphonated derivative dihydroxyethyl derivative, therefore contains the same organic functional groups, but due to the sulphonation/salification degree is less soluble. This property makes the Read Across substance 3a-A(free acid) a conservative representative because of the potential higher bioavailability.

As a conclusion, it can be stated that the substance is not acutely toxic for all the three exposure ways.

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), 3.1 Acute toxicity section, substances can be allocated to one of four toxicity categories based on acute toxicity by the oral, dermal or inhalation route according to the numeric criteria. Acute toxicity values are expressed as (approximate) LD50 (oral, dermal) or LC50 (inhalation) values or as acute toxicity estimates (ATE).

The oral LD50 value was established to be greater than 10000 mg/kg body weight, therefore the test substance is out of any classification limit for acute oral toxicity (oral acute toxicity category 4: 300 < ATE ≤ 2000 mg/kg bw).

The dermal LD50 value was established to exceed 2000 mg/kg body weight, which exceeded the highest CLP classification limit (dermal acute toxicity category 4: 1000 < ATE ≤ 2000 mg/kg bw).

The inhalation LC50 value was established to be greater than 1895 mg/m3. For powder the limit for classification is ATE > 5 mg/l i. e. 5000 mg/m3.

Since no effect was observed at the tested concentration and this was the maximum reachable concentration in the test condition, it is assumed that the substance is not classified for inhalation acute toxicity.

In conclusion, the available experimental data are adequate for classification and labelling and the test substance is non classified for oral and dermal acute toxicity, according to the CLP Regulation (EC 1272/2008).