Strontium 4-[(5-chloro-4-methyl-2-sulphonatophenyl)azo]-3-hydroxy-2-naphthoate (1:1)

Endpoint summary

Description of key information

Studies of Pigment Red 48:3 and of other members of the same category indicate that Pigment Red 48:3 is not acutely toxic via the oral, inhalation, and dermal route of exposure.

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

Study period:

1972

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

non GLP, no necropsy performed. Little information on test item

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

yes

Remarks:

higher doses and more animals, only 8 days post-observation.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Specific details on test material used for the study:

- Test substance was present in a mixture
- Manufacture date: 6.8.71
- Company identifier: TK 10340
- Product containing mainly the sodium salt of pigment red 48. The content of Pigment red 48:3 is 29%.

Species:

rat

Strain:

other: CFE

Sex:

male/female

Details on test animals or test system and environmental conditions:

Healthy young random bred rats of the CFE (RAC, SPF) strain purchased from the breeder were used for these experiments. The mean initial body weight was between 127 and 138 g. Before starting, the animals were acclimatized for at least 5 days in our laboratories to a constant room temperature of 22°C, relative humidity of 55 % and 14 hours light/day. They were housed in groups of 5 in macrolon cages (size 3). A standard diet of Nafag and drinking water were given "ad libitum".

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

Rats received by gavage various doses of a preparation suspended with 0.5% carboxymethyIcellulose and tap water. The total volume given was 20 mL/kg body weight.

Doses:

5000 and 10000 mg/kg bw (containing 2900 mg/kg bw of Pigment Red 48:3)

No. of animals per sex per dose:

- 5000 mg/kg bw: 5/sex
- 10000 mg/kg bw: 3 males and 2 females

Control animals:

no

Details on study design:

Symptoms and mortality after administration were recorded during an observation period of 8 days.

Key result

Sex:

male/female

Dose descriptor:

LD0

Effect level:

>= 2 900 mg/kg bw

Remarks on result:

other: calculated on content of Pigment Red 48:3

Gross pathology:

not performed

Other findings:

- Other observations: red stained feces at both doses, red stained urine at 10000 mg/kg bw

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 900 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

Please see the category read-across justification in the category object.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 1 518 mg/m³ air

Based on:

other: read-across

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 4.76 mg/L air

Based on:

other: read-across

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LC50

Value:

1 518 mg/m³ air

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Justification for type of information:

Please see the category read-across justification in the category object.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 500 mg/kg bw

Based on:

other: read-across

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 500 mg/kg bw

Additional information

Acute oral toxicity

Pigment Red 48:3 is of low acute oral toxicity (LD50 > 2900 mg/kg bw) as calculated from a study with a product containing both the sodium salt and the strontium salt (Ciba 1972). In deviation to the OECD testing guideline, the observation period was only 8 days and gross pathology was not performed. In the absence of mortality and considering the presence of the analogue sodium salt, the study is considered acceptable for hazard assessment. In addition, poorly documented data indicates absence of mortality after a single oral dose of 15000 mg/kg bw (Synthesia 1989).

Data on a moiety of Pigment Red 48:3 is also available (4-amino-6-chlorotoluene-3-sulphonic acid; CAS 88-51-7). This moiety is not acutely toxic via the oral route (LD50 >7500 mg/kg bw).

Acute inhalation toxicity

The hazard of acute inhalation toxicity is derived from experimental data on analogue pigments present in the category. A valid study is available for Pigment Red 57:1 which differs from Pigment Red 48:3 by the presence of a chlorine and Ca2+ instead of Sr2+. In addition, a valid study is available for Pigment Red 48:1 which is of lower water solubility as it contains Ba2+ instead of Sr2+. Acute inhalation exposure to aerosol of Pigment Red 48:1 at a concentration of 4.76 mg/L caused mortality in one of ten rats (Capelle 1993) as assessed in a GLP compliant study following OECD testing guideline 403. The study with Pigment Red 57:1 (Sachsse 1976) was performed in rats with a commercial product following a protocol which is comparable to OECD testing guideline 403 (1981). A limit test was performed with the highest concentration of dust that was technically achievable (1518 ± 176 mg/m3 air). No mortality, no clinical signs and no findings upon necropsy were observed.

Data on a moiety (sulfonated phenylring) of Pigment Red 48:3 is also available (4-amino-6-chlorotoluene-3-sulphonic acid; CAS 88-51-7). This moiety is not acutely toxic via the inhalation route (LC50 >13.0 mg/L).

Acute dermal toxicity

The hazard of acute dermal toxicity is derived from experimental data on analogue pigments (48:1, 48:2, 48:3, and 57:1) present in the category. For these pigments, the LD50s all exceeded 2500 mg/kg bw. As a result, it can be concluded that Pigment Red 48:3 is also not acutely toxic via the dermal route.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes. As a result the substance is not considered to be classified for acute oral, dermal or inhalation toxicity according to Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008.