Dapson SDS/MSDS (Safety Data Sheet)

3.1 Substances
Product name: Dapson
CAS Number: 80-08-0
PubChem CID: 2955
Molecular formula: C12H12N2O2S
Molecular weight: 248.30 g/mol
IUPAC name: 4-(4-aminophenyl)sulfonylaniline

3.2 Mixtures
Not applicable (pure substance).

4.1 Description of first aid measures
Inhalation: INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater
Skin contact: SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.
Eye contact: EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.
Ingestion: INGESTION: DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport

4.2 Most important symptoms and effects, both acute and delayed
See Section 11 (Toxicological Information).

4.3 Indication of any immediate medical attention and special treatment needed
Treat symptomatically. Contact a poison control center or physician for severe exposure.

5.1 Extinguishing media
Suitable: Water spray, dry chemical, carbon dioxide (CO2), alcohol-resistant foam.
Unsuitable: None known.

5.2 Specific hazards arising from the substance or mixture
Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher. A water spray may also be used. (NTP, 1992)
Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.

5.3 Advice for firefighters
Wear self-contained breathing apparatus (SCBA) and full protective clothing.
Fight fire from upwind. Cool containers with water spray until fire is extinguished.
Flash point: greater than 320 °F (NTP, 1992)

6.1 Personal precautions, protective equipment and emergency procedures
Wear appropriate personal protective equipment (see Section 8).
Avoid breathing dust/vapor. Ensure adequate ventilation.
Evacuate personnel to safe areas. Keep people away from and upwind of spill.

6.2 Environmental precautions
Prevent product from entering drains, waterways, or soil.
Contain spill with inert absorbent material.

6.3 Methods and materials for containment and cleaning up
ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust; Environmental precautions: Do not let product enter drains; Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.
SRP: Expired or waste pharmaceuticals shall carefully take into consideration applicable DEA, EPA, and FDA regulations. It is not appropriate to dispose by flushing the pharmaceutical down the toilet or discarding to trash. If possible return the pharmaceutical to the manufacturer for proper disposal being careful to properly label and securely package the material. Alternatively, the waste pharmaceutical shall be labeled, securely packaged and transported by a state licensed medical waste contractor to dispose by burial in a licensed hazardous or toxic waste landfill or incinerator.
Product: Offer surplus and non-recyclable solutions to a licensed disposal company; Contaminated packaging: Dispose of as unused product.
SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Further processing of solid materials may result in the formation of combustible dusts. The potential for combustible dust formation should be taken into consideration before additional processing occurs. Provide appropriate exhaust ventilation at places where dust is formed.
Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.
Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.
SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.

7.1 Precautions for safe handling
SMALL SPILLS AND LEAKAGE: If a spill of this chemical occurs, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with acetone and transfer the dampened material to a suitable container. Use absorbent paper dampened with acetone to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.
STORAGE PRECAUTIONS: You should protect this chemical from exposure to light. Keep the container tightly closed under an inert atmosphere, and store under refrigerated temperatures. (NTP, 1992)
Keep container tightly closed in a dry and well-ventilated place. Light sensitive.
Dapsone tablets should be stored at 20-25 °C and protected from light. Dapsone may discolor following exposure to light.

7.2 Conditions for safe storage, including any incompatibilities
Keep container tightly closed in a dry and well-ventilated place. Light sensitive.
Dapsone tablets should be stored at 20-25 °C and protected from light. Dapsone may discolor following exposure to light.
Store away from incompatible materials (see Section 10).
[Note: Specific storage temperature not available in public databases. Refer to supplier Certificate of Analysis (COA) for exact storage conditions.]

9.1 Information on basic physical and chemical properties
a) Appearance: 4,4'-sulfonyldianiline appears as odorless white or creamy white crystalline powder. Slightly bitter taste. (NTP, 1992)
b) Odor: Odorless
c) Odor threshold: No data available
d) pH: No data available
e) Melting point/freezing point: 347 to 349 °F (NTP, 1992)
f) Initial boiling point and boiling range: No data available
g) Flash point: greater than 320 °F (NTP, 1992)
h) Evaporation rate: No data available
i) Flammability (solid, gas): No data available
j) Upper/lower flammability or explosive limits: No data available
k) Vapor pressure: 0.00000003 [mmHg]
l) Vapor density: No data available
m) Relative density: 1.33 at 77 °F (NTP, 1992) - Denser than water; will sink
n) Water solubility: less than 1 mg/mL at 68 °F (NTP, 1992)
o) Partition coefficient: n-octanol/water: Log P (n-octanol/water): 1
p) Auto-ignition temperature: No data available
q) Decomposition temperature: No data available
r) Viscosity: No data available
s) Explosive properties: No data available
t) Oxidizing properties: No data available

9.2 Other information
Topological Polar Surface Area (TPSA): 94.6 Ų
Complexity: 306

11.1 Information on toxicological effects
Acute toxicity:
No acute toxicity data available.
Skin corrosion/irritation:
No data available.
Serious eye damage/eye irritation:
No data available.
Respiratory or skin sensitization:
No data available.
Germ cell mutagenicity:
No data available.
Carcinogenicity:
No data available.
Reproductive toxicity:
No data available.
Specific target organ toxicity (single exposure):
H371, H372, H373
Specific target organ toxicity (repeated exposure):
No data available.
Aspiration hazard:
No data available.

11.2 Additional information
Carcinogen classification:
Dapsone
Group 3: Not classifiable as to its carcinogenicity to humans
Volume 24: (1980) Some Pharmaceutical Drugs
Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)
1987
1987
4,4'-Sulfonyldianiline (Dapsone)
TR-020: Bioassay of Dapsone for Possible Carcinogenicity (CASRN 80-08-0) (1977 )
07/25/77
Clear Evidence
No Evidence
No Evidence
No Evidence
It is concluded that under the conditions of thi
Exposure routes:
Ingestion (L1039, T14); dermal (L1039, T14) ; eye contact (L1039, T14); inhalation (L1039, T14)
Bioavailability is 70 to 80% following oral administration.
Signs and symptoms of exposure:
Overdosage might be expected to produce nasal congestion, syncope, or hallucinations. Measures to support blood pressure should be taken if necessary.
Data source: Hazardous Substances Data Bank (HSDB) via PubChem.

12.1 Toxicity
Dapsone's production and use and administration in skin infections and leprosy treatment, as an antibiotic in veterinary medicine, as a hardening agent in the curing of epoxy resins and as an analytical reagent may result in its release to the environment through various waste streams. If released to air, an estimated vapor pressure of 2.7X10-8 mm Hg at 25 °C indicates dapsone will exist in both the vapor and particulate phases in the atmosphere. Vapor-phase dapsone will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 0.23 days. Particulate-phase dapsone will be removed from the atmosphere by wet and dry deposition. Dapsone in aqueous media, was completely photodegraded in 6 hours following exposure to sunlight irradiation and, therefore, may be susceptible to direct photolysis. If released to soil, dapsone is expected to have moderate mobility based upon an estimated Koc of 260. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 3.1X10-14 atm-cu m/mole. Dapsone is not expected to volatilize from dry soil surfaces based upon its vapor pressure. Biodegradation data in soil or water were not available. If released into water, dapsone is expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is not expected to be an important fate proc

12.2 Persistence and degradability
No data available.

12.3 Bioaccumulative potential
Log P (n-octanol/water): 1
Low potential for bioaccumulation (Log P < 3).

12.4 Mobility in soil
No data available.

12.5 Results of PBT and vPvB assessment
PBT/vPvB assessment not available.

12.6 Other adverse effects
This substance is classified as hazardous to the aquatic environment.

13.1 Waste treatment methods
Waste Treatment Methods: Waste material must be disposed of in accordance with national and local regulations. Leave chemicals in original containers and do not mix with other waste. Handle uncleaned containers in the same manner as the product itself.

14.1 UN number
Not regulated as dangerous goods (research quantities typically exempt).

14.2 UN proper shipping name
Not subject to transport regulations (small quantities for research use).

14.3 Transport hazard class(es)
Not classified as dangerous goods for transport (research quantities).

14.4 Packing group
Not applicable (not regulated as dangerous goods in typical research quantities).

14.5 Environmental hazards
Marine pollutant: Yes (classified as environmentally hazardous per GHS).

14.6 Special precautions for user
Transport in original packaging. Ensure containers are tightly sealed.
For bulk or commercial quantities, consult applicable transport regulations (DOT, IATA, IMDG).

14.7 Transport in bulk according to Annex II of MARPOL 73/78 and the IBC Code
Not applicable.

15.1 Safety, health and environmental regulations/legislation specific for the substance or mixture
US EPA / TSCA: Subject to EPA TSCA regulations
EU ECHA / REACH: Registered (REACH Active)

SARA 302 Components:
No chemicals in this material are subject to the reporting requirements of SARA Title III, Section 302.
SARA 313 Components:
This material does not contain any chemical components with known CAS numbers that exceed the threshold (De Minimis) reporting levels established by SARA Title III, Section 313.
SARA 311/312 Hazards:
Acute (short-term) health hazard
Chronic (long-term) health hazard
Environmental hazard

Massachusetts Right To Know Components:
This material contains components subject to the Massachusetts Right to Know Act. See Section 2 for hazard classification.
Pennsylvania Right To Know Components:
This material contains components subject to the Pennsylvania Right to Know Act. See Section 2 for hazard classification.
New Jersey Right To Know Components:
This material contains components subject to the New Jersey Right to Know Act. See Section 2 for hazard classification.

California Prop. 65 Components:
This product does not contain any chemicals known to the State of California to cause cancer, birth defects, or any other reproductive harm.

Other regulatory listings:
- The Australian Inventory of Industrial Chemicals: Chemical: Benzenamine, 4,4'-sulfonylbis-
- EFSA Legal Basis: Regulation (EC) No 1935/2004 (amended)
- TSCA Requirements: Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329. Effective date: 9/30/91; Reporting date: 11/27/91.
Pursuant to section 8(d) of TSCA, EPA pr

15.2 Chemical safety assessment
A chemical safety assessment has not been carried out for this substance.
For research-use-only compounds, no CSA is required under REACH Annex I.

Revision Date: 2026/09/09
Further Information: The information provided is believed to be correct but is not exhaustive and should be used only as a guideline based on current knowledge. It does not represent a guarantee of the properties of the product. Selleck Chemicals Corporation and its Affiliates shall not be held liable for any damage resulting from handling or contact with the product.