Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Dapsone

Dapsone is crystals from 95% ethanol and is odorless.

CAS 80-08-0 Warning

01 · Identification

What Dapsone is

Dapsone is crystals from 95% ethanol and is odorless. It melts at 80 °C, is practically insoluble in water.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Dapsone identifiers and molecular data

Dapsone CAS number and EC number

CAS number80-08-0
EC number201-248-4
Index number (CLP Annex VI)612-084-00-1

Other names for Dapsone

  • 4,4'-diamino diphenyl sulfone

03 · GHS classification

Dapsone hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Dapsone pictograms and signal word

Signal wordWarning

Dapsone hazard class and category

GHS hazard classes Dapsone falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07

Dapsone hazard statements (H-codes)

Hazard statements assigned to Dapsone
CodeHazard statement
H302 Harmful if swallowed.

This page lists only the codes assigned to Dapsone. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Dapsone

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Dapsone issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Dapsone precautionary statements

CLP Annex VI assigns 4 precautionary statements to Dapsone. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Prevention

What to do before and during handling so the hazard never happens.

Response

What to do once exposure, spillage or fire has already happened.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Dapsone name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български дапсон 4,4′-диаминодифенилсулфон
Spanish español Dapsona 4,4'-diamino-difenil-sulfona
Czech čeština dapson 4,4'-diaminodifenylsulfon
Danish dansk dapson 4,4'-diaminodiphenylsulfon
German Deutsch Dapson 4,4'-Diaminodiphenylsulfon
Estonian eesti dapsoon 4,4'-diaminodifenüülsulfoon
Greek ελληνικά δαψόνη 4,4′-διαμινοδιφαινυλοσουλφόνη
English English dapsone 4,4'-diamino diphenyl sulfone
French français dapsone 4,4'-diaminodiphénylsulfone
Croatian hrvatski dapson 4,4'-diamino difenil sulfon
Italian italiano dapsone 4,4'-diaminodifenilsulfone4,4'-sulfonildianilina
Latvian latviešu dapsons 4,4'-diaminodifenilsulfons
Lithuanian lietuvių dapsonas 4,4'-diaminodifenilsulfonas
Hungarian magyar dapszon 4,4’-diaminodifenilszulfon
Maltese Malti dapson sulfon tad-difenil ta' 4,4'-diammino
Dutch Nederlands dapsone 4,4'-diaminodifenylsulfon
Polish polski dapson sulfon bis(4,4'-aminofenylowy)
Portuguese português dapsona 4,4'-diaminodifenilsulfona
Romanian română dapson 4,4'-diamino difenil sulfonă
Slovak slovenčina dapsón bis(4-aminofenyl)sulfón4,4’-sulfonyldianilín
Slovenian slovenščina dapson 4,4'-diamino difenil sulfon
Finnish suomi dapsoni di(4-aminofenyyli)sulfoni
Swedish svenska dapson 4,4'-diaminodifenylsulfon

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Dapsone GHS label elements

Everything CLP Annex VI fixes for Dapsone, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogram

Warning

Dapsone

  • Harmful if swallowed.
  • Do not eat, drink or smoke when using this product.
  • IF SWALLOWED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Dapsone in the GHS label constructor →

07 · Health hazards

Dapsone health hazards and exposure limits

Dapsone hazard summary

Some of the most commonly used curing agents in the advanced composite industry are the aromatic amines. Two of the most common are 4,4'-methylene-dianiline (MDA) and 4,4'-sulfonyldianiline (DDS). Like the epoxies, these compounds have a very low vapor pressure and usually do not present an airborne hazard unless in a mixture that is sprayed or cured at high temperatures. However, potential for dermal exposure is frequently high. The aromatic amines may permeate many of the commonly used protective gloves and thus may be particularly difficult to protect against . . . . Another of the amines, DDS, has a significant amount of toxicological data as its pharmaceutical grade, Dapsone, has been used for years to treat leprosy and certain types of chronic dermal inflammation. However, at low airborne concentrations, there are no known effects from workplace exposure. [OSHA Technical Manual: Advanced Composites] Methemoglobinemia, hemolytic anemia, and liver injury have been reported after toxic ingestion. [HSDB] The therapeutic range for adults is 50-300 mg/day. 5-12% methemoglobinemia has been reported in patients taking 100 mg/day chronically. Hemolysis has not been reported in adult patients taking less than 300 mg/day. [Olson, p. 211]

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Dapsone carcinogenicity classification

IARC classification Group 3 — Not classifiable as to its carcinogenicity to humans
IARC monographs Volume 24: (1980) Some Pharmaceutical Drugs

Studied by the US National Toxicology Program: TR-020: Bioassay of Dapsone for Possible Carcinogenicity (CASRN 80-08-0) (1977 )

Inadequate evidence of carcinogenicity in humans. Limited evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 3: The agent is not classifiable as to its carcinogenicity to humans.

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · Physical and chemical properties

Dapsone properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Dapsone melting point

Property Value Conditions Source
Melting point 80 °C (176 °F) between HSDB
176 °C (348.8 °F) DOE PAC
175.5 °C (347.9 °F) range, midpoint shown HSDB

Dapsone density

Property Value Conditions Source
Density 1.33 g/cm³ at 25 °C CAMEO

Dapsone solubility

Property Value Conditions Source
Solubility Soluble in alcohol, methanol, acetone, dilute hydrochloric acid. Practically insoluble in water. HSDB
Insoluble in fixed and vegetable oils. HSDB
Slightly soluble in deuterated dimethyl sulfoxide. HSDB

Dapsone vapor pressure

Property Value Conditions Source
Vapor pressure 3e-8 mmHg Haz-Map

Dapsone flash point

Property Value Conditions Source
Flash point 160 °C (320 °F) above this value CAMEO

Dapsone vapor density

Property Value Conditions Source
Vapor density 8.3 (air = 1) HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Handling and storage

Dapsone storage and handling

Dapsone storage conditions

Keep container tightly closed in a dry and well-ventilated place. Light sensitive.

Source: Hazardous Substances Data Bank (HSDB)

Dapsone incompatible materials

Incompatible materials: Strong oxidizing agents

Source: Hazardous Substances Data Bank (HSDB)

Dapsone reactivity

4,4'-SULFONYLDIANILINE can neutralize acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated in combination with strong reducing agents, such as hydrides. Incompatible with strong oxidizing agents. Also incompatible with epoxy resins under uncontrolled conditions (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Dapsone in the storage compatibility matrix →

10 · Questions

Dapsone — frequently asked questions

What is the CAS number of Dapsone?

The CAS number of Dapsone is 80-08-0. Its EC number is 201-248-4.

What does a Dapsone label have to show?

Under CLP Annex VI the label for Dapsone carries the pictogram Exclamation mark and the signal word is Warning.

Is Dapsone flammable?

CLP Annex VI assigns Dapsone no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it. The flash point reported for it is 160 °C (320 °F), above this value (CAMEO).

Is Dapsone a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Dapsone. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health. IARC places it in Group 3: not classifiable as to its carcinogenicity to humans.

What is the melting point of Dapsone?

The melting point reported for Dapsone is 80 °C (176 °F), between (HSDB).

How should Dapsone be stored?

Keep container tightly closed in a dry and well-ventilated place. Light sensitive. (Hazardous Substances Data Bank (HSDB))

Nearby

Substances next to Dapsone

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