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Administrative data

Description of key information

Oral 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:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
August form 9th to 28th, 2006
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
The usage of information on Direct Blue 199_Na, which has the same main component and with a different counter ion, can be considered as suitable and appropriated because the difference in salification is expected to not influence the characteristics related to the specific end-point.
The impurity profile does not impact on the read across proposed. Details on the approach followed are included in the document attached to the IUCLID section 13.
Reason / purpose:
read-across source
Qualifier:
according to
Guideline:
OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)
Version / remarks:
adopted 17 December 2001
GLP compliance:
yes
Test type:
acute toxic class method
Limit test:
yes
Species:
rat
Strain:
Sprague-Dawley
Sex:
female
Details on test animals and environmental conditions:
Females were fasted.
Route of administration:
oral: unspecified
Vehicle:
water
Remarks:
distilled
Doses:
2000 mg/kg bw
No. of animals per sex per dose:
Two groups of three female: three female were treated, followed by a further group of three females at the same dose level.
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of clinical and mortality observations: monitored during the study.
- Necropsy of survivors performed: all animals were subjected to gross necropsy.
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
No deaths recorded.
Clinical signs:
No signs of systemic toxicity were observed.
Gross pathology:
Kidneys of all the females appeared stained green; in one case dark liver was observed.

Individual Clinical observations and mortality data

Animal number Effects noted
Hours after dosing Days after dosing
½ 1 2 4 1* 2* 3* 4 5 6 7 8 9 10 11 12 13 14
1 - 0 0 0 0 0 U 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0
1 - 1 0 0 0 0 U 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0
1 - 2 0 0 0 0 U 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0
2 - 0 0 0 0 0 U 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0
2 - 1 0 0 0 0 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0
2 - 2 0 0 0 0 0 F U 0 F U 0 F U 0 0 0 0 0 0 0 0 0 0 0

0 = no signs of systemic toxicity

F = Faeces stained blue

U = Urine stained blue

* = Bedding stained blue

Individual Bodyweights and bodyweight changes

Animal number Bodyweight (g) at day Bodyweight gain (g) during week
Day 1 Day 7 Day 14 1 2
1 - 0 214 239 256 25 17
1 - 1 200 217 237 17 20
1 - 2 211 241 268 30 27
2 - 0 203 226 243 23 17
2 - 1 203 237 249 34 12
2 - 2 186 226 240 40 14

Individual Necropsy Findings

Animal number Macroscopic observations
1-0 Kidneys: stained green
1-1 Liver: dark, Kidneys: stained green
1-2 Kidneys: stained green
2-0 Kidneys: stained green
2-1 Kidneys: stained green
2-2 Kidneys: stained green
Interpretation of results:
other: not classified, according to the CLP Regulation (EC 1272/2008)
Conclusions:
LD50 > 2000 mg/kg bw
Executive summary:

The present study was carried out to assess acute toxicity following a single oral administration to rats of the test substance to Sprague-Dawley CD strain rats, according to OECD Guideline 423. A group of three fasted females was treated with the test material at a dose level of 2000 mg/kg bw. This was followed by a further group of three fasted females at the same dose level. The test material was administered orally as a solution in distilled water. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy.

At the end of the study period, there was no mortality and no signs of systemic toxicity. No significant macroscopic alterations were observed in any of the major organs of the examined animals. Under the test conditions, LD50 was estimated to be greater than 2000 mg/kg bw.

Conclusion

LD50 > 2000 mg/kg bw

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

ACUTE TOXICITY - ORAL ROUTE

The oral acute toxicity of Direct Blue 199 was investigated in a study performed in Sprague-Dawley CD rats, according to OECD Guideline 423. The already existing experiment was performed on the Direct Blue 199_Na. The usage of information on Direct Blue 199_Na, which has the same main component and with a different counter ion, can be considered as suitable and appropriated because the difference in salification is expected to not influence the characteristics related to the specific end-point. The impurity profile does not impact on the read across proposed. Details on the approach followed are included in the document attached to the IUCLID section 13.

A group of three fasted females was treated with the test material at a dose level of 2000 mg/kg bw. This was followed by a further group of three fasted females at the same dose level. The test material was administered orally as a solution in distilled water. At the end of the study period, there was no mortality and no signs of systemic toxicity. No significant macroscopic alterations were observed in any of the major organs of the examined animals.

 

A second supporting study is available on Direct Blue 199_Na; despite the test method seems to be scientifically acceptable, many details are missing on both test procedures and on the study results. Furthermore, there are no information about the lot tested. 1.5 g of test compound was suspended in 3 ml of deionised water to make 3.8 ml of suspension. Animals were dosed at a rate of 20 ml/kg (equivalent to 8 g/kg of test compound). The suspension was administered as a single dose by gavage to ten rats. After administration of the compound, the animals were observed for 7 days. No deaths occurred and no clinical symptoms were recorded. Apart from staining of the kidneys an autopsy examination did not reveal any lesions caused by the administration of the test item.

 

Furthermore, a summary reporting some toxicological test results is available on Direct Blue 199b; unfortunately the original study reports cannot be more consulted. The available information included in the toxicological test results summary indicate that the substance is not acutely harmful for oral route: an oral LD50 of ca 8500 mg/kg was indicated. Dyspnoea, tumbling, position of rats are the effects reported above 5000 mg/kg bw. Furthermore, eyes, ears, extremities, fur and tails were turned blue and general organ discoloration, cardiac or gastric dilatation, diarrhoea were noted.

The reference substance under registration is the Direct Blue 199, the form which can have a variable number of the sulfonamide groups; in the Direct Blue 199b substance, this functional group can be found in a molar amount average of 0.5. Thus, although it has been appointed a different CAS number respect to the Direct Blue 199b, it can be considered as “included” into the structure variability of the Direct Blue 199.

 

ACUTE TOXICITY - INHALATION ROUTE

No acute toxicity studies by inhalation route are available on Direct Blue 199.

Nevertheless, because of the physical state of the substance inhalation is not an appropriate route of exposure. Particle size distribution showed that the 90 % of particles has a diameter lower than 65.4 µm and that only the 10 % of particles has a diameter lower than 20.1 µm. Thus, most of the Direct Blue 199 particles are expected to remain in the upper respiratory tract, which is characterized by efficacious defence mechanisms able to remove them; therefore, respirable particles, able to enter the deepest part of the lung, the non-ciliated alveoli (i.e. D50 of 4 µm), can be considered a minimal portion. This consideration, together with the consideration that the substance is manufactured and handled with suitable risk management measures and with the suitable personal protective equipments, lets to consider the possible absorption of the substance by inhalation route as negligible.

 

ACUTE TOXICITY - DERMAL ROUTE

The inhalation and the skin contact of Direct Blue 199 are unlikely. According to the Commission Regulation (EU) 2016/863, amending Annexes VII and VIII to REACH Regulation (EC 1907/2006) as regards skin corrosion/irritation, serious eye damage/eye irritation and acute toxicity, testing by the dermal route does not need to be conducted if no systemic effects have been observed in in vivo studies with dermal exposure (e.g. skin irritation, skin sensitisation). Furthermore, it is explained that recent scientific analysis of available data from in vivo acute toxicity studies have shown that substances that are not toxic via the oral route may be expected with high certainty to be also non-toxic via the dermal route. Therefore, testing those substances via the dermal route does not provide essential information for their safety assessment.

The amendment is the consequence of studies and scientific debates. In particular, the 15th Meeting of Competent Authorities for REACH and CLP (CARACAL, 2014) concluded that an adaptation of point 8.5.3 of Annex VIII to REACH is justified in order to not require information on acute dermal toxicity for substances that have shown no toxicity in acute oral toxicity test up to the limit dose of 2000 mg/kg bw.

 

In the oral acute toxicity test, no signs of systemic toxicity were recorded. The skin sensitisation potential was investigated in both Local Lymph Node Assay (LLNA) in Mice and in Albino Guinea Pigs Maximization Test (GPMT). In the LLNA assay no test item-related clinical signs were observed. In the GMPT assay no toxic symptoms were evident in the guinea pigs of either the control nor test group; no death occurred. No reason of concern is raised on the basis of the skin/eye irritation investigations.

 

REFERRENCE

CARACAL, 2014. 15th Meeting of Competent Authorities for REACH and CLP (CARACAL), 8 – 9 July 2014. Charlemagne building, Brussels, Belgium. Brussels, 26 July 2014. Doc. CA/61/2014. Stakeholder proposal to modify REACH standard information requirements for acute toxicity (REACH Annex VIII, point 8.5)

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 2000 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).

Dermal and inhalation exposure is unlikely, thus no acute toxicity value is available and no further investigation is required.

In conclusion, the test substance is non classified for oral acute toxicity, according to the CLP Regulation (EC 1272/2008).