3,3'-sulphonyldianiline

Endpoint summary

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

1 200 mg/kg bw

Quality of whole database:

There are many studies, incl. human experience, on acute toxic effects. In most species investigated acute toxicity is observed above 600 mg/kg bw. It is estimated from several studies that the LD50 is above 1000 mg/kg bw and below 2000 mg/kg bw.

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

key study

Study period:

1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study has been performed under GLP and in compliance with guideline. The read-across of toxicological data is considered justified because 4,4’-DDS (dapsone) and 3,3’-DDS are structural isomers with identical mol mass, identical elemental composition and identical functional groups. To the best of our knowledge, only Dapsone is used as a pharmaceutical. It is not known whether 3,3’-DDS acts as 4,4’-DDS as a folate synthesis inhibitor in microorganisms.The main toxicological hazard of 4,4’-DDS is the methemoglobin formation. This is due to the aromatic amine substituent of the molecule, which is present in both isomers. It is concluded that the main toxicological hazard of 3.3’-DDS is also methemoglobin formation. Both isomers do not show a structural alert for mutagenicity. The toxicological and ecotoxicological hazard profiles of both isomers are considered to be identical. A read-across 1:1 is considered reasonable and justified due to the very small structural difference of both substances.

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPP 81-2 (Acute Dermal Toxicity)

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Type of coverage:

occlusive

Details on dermal exposure:

TEST SITE
- Area of exposure: back of the animal (shaved)
- Type of wrap if used: polyethylene plastic

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2g/kg bw
- Constant volume or concentration used: yes/no no
- For solids, paste formed: yes, 1% in a gel paste

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

Each 5 males and 5 females

Control animals:

not required

Details on study design:

Ten rabbits (5 per gender) were used. The back of each animal was haved. Half the animals received epidermal abrasions on the shaved area. The test article (1% dapsone gel) was applied to the back of each animal at a dose of 2g/kg and covered with polyethylene plastic. The rabbits were fitted with collars and the test article was left in place for 24 hours. The test sites were then wiped clean and the rabbits were monitored for 14 days for signs of illness, mortality,, and dermal reactions (erythema and edema) at the site of application. Body weights were recorded at the time of dosing and after 14 days.

Preliminary study:

Very slightly (barely perceptible) erythema was observed for the first 7 to 12 days after treatment; this may have been due to shaving, occlusion, taping, etc. No edema was observed. No effects on body weight, survival, clinical signs, or gross necropsy were observed.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

act. ingr.

Mortality:

None

Clinical signs:

other: Very slightly (barely perceptible) erythema was observed for the first 7 to 12 days after treatment; this may have been due to shaving, occlusion, taping, etc. No edema was observed.

Gross pathology:

No effect

Other findings:

none

Interpretation of results:

practically nontoxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

LD50 (dermal) > 2000 mg/kg. No clinical signs of toxicity

Executive summary:

The dermal LD50 in the rabbit is > 2000 mg/kg. No clinical signs observed.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Additional information

Justification for selection of acute toxicity – oral endpoint
Under test conditions in rabbit, LD0 value is 600 mg/kg bw with no toxic effect detectable, and LDLo range is 700 to 910 mg/kg with self-mutilations observed which indicates a low toxicity. Also a variety of acute oral toxicity studies with Dapsone as a pharmaceutical have been conducted in humans and the range of TDlows when the substance is orally applied is 18 - 37.5 mg/kg bw which confirms a low toxicty as well in Human.

Justification for classification or non-classification

The substance is classified for acute oral toxicity (Cat 4) with an LD50 >1000 mg/kg bw. The substance is also classified for Specific Target Organ Toxicity after single exposure Category 2 for effects on blood due to methemoglobin formation. There is no classification required for acute toxicity on the dermal route.