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

2,4-DB (ISO)

2,4-DB (ISO) is white crystals with a slightly phenolic odor.

CAS 94-82-6 C10H10Cl2O3 249.09 g/mol Warning

01 · Identification

What 2,4-DB (ISO) is

2,4-DB (ISO) is white crystals with a slightly phenolic odor. Its molecular formula is C10H10Cl2O3 and its molecular weight is 249.09 g/mol. It melts at 119 °C.

Under the GHS it carries the signal word Warning.

02 · Identifiers

2,4-DB (ISO) identifiers and molecular data

2,4-DB (ISO) CAS number and EC number

CAS number94-82-6
EC number202-366-9
Index number (CLP Annex VI)607-083-00-8

2,4-DB (ISO) molecular formula and molecular weight

Molecular formulaC10H10Cl2O3
Molecular weight249.09 g/mol

Other names for 2,4-DB (ISO)

  • 4-(2,4-dichlorophenoxy)butyric acid

03 · GHS classification

2,4-DB (ISO) hazard classification

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

2,4-DB (ISO) pictograms and signal word

Signal wordWarning

2,4-DB (ISO) hazard class and category

GHS hazard classes 2,4-DB (ISO) falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 2 H411 GHS09

2,4-DB (ISO) hazard statements (H-codes)

Hazard statements assigned to 2,4-DB (ISO)
CodeHazard statement
H302 Harmful if swallowed.
H411 Toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to 2,4-DB (ISO). 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 2,4-DB (ISO)

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 2,4-DB (ISO) 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

2,4-DB (ISO) precautionary statements

CLP Annex VI assigns 7 precautionary statements to 2,4-DB (ISO). 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.

Disposal

What has to happen to the contents and the empty container.

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

2,4-DB (ISO) 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 2,4-DB (ISO) 4-(2,4-дихлорофенокси)маслена киселина
Spanish español 2,4-DB (ISO) ácido 4-(2,4-diclorofenoxi)butírico
Czech čeština 2,4-DB (ISO) 4-(2,4-dichlorfenoxy)butanová kyselina
Danish dansk 2,4-DB (ISO) 4-(2,4-dichlorphenoxy)smørsyre
German Deutsch 2,4-DB (ISO) 4-(2,4-Dichlorphenoxy)buttersäure
Estonian eesti 2,4-DB (ISO) 4-(2,4-diklorofenoksü)võihape
Greek ελληνικά 2,4-DB (ISO) 4-(2,4-διχλωροφαινοξυ)βουτυρικό οξύ
English English 2,4-DB (ISO) 4-(2,4-dichlorophenoxy)butyric acid
French français 2,4-DB (ISO) acide 4-(2,4-dichlorophénoxy)butyrique
Croatian hrvatski 2,4-DB (ISO) 4-(2,4-diklorfenoksi)maslačna kiselina
Italian italiano 2,4-DB (ISO) acido 4-(2,4-diclorofenossi)butirrico
Latvian latviešu 2,4-DB (ISO) 4-(2,4-dihlorfenoksi)sviestskābe
Lithuanian lietuvių 2,4-DB (ISO) 4-(2,4-dichlorfenoksi)butano rūgštis
Hungarian magyar 2,4-DB (ISO) 4-(2,4-diklórfenoxi)butánsav
Maltese Malti 2,4-DB (ISO) aċidu 4-(2,4-diklorofenossi)butiriku
Dutch Nederlands 2,4-DB (ISO) 4-(2,4-dichloorfenoxy)boterzuur
Polish polski 2,4-DB (ISO) kwas 4-(2,4-dichlorofenoksy)butanowy
Portuguese português 2,4-DB (ISO) ácido 4-(2,4-diclorofenoxi)butírico
Romanian română 2,4-DB (ISO) acid 4-(2,4-diclorofenoxi) butiric
Slovak slovenčina 2,4-DB (ISO) kyselina 4-(2,4-dichlórfenoxy)butánová
Slovenian slovenščina 2,4-DB (ISO) 4-(2,4-diklorofenoksi)maslena kislina
Finnish suomi 2,4-DB (ISO) 4-(2,4-dikloorifenoksi)voihappo
Swedish svenska 2,4-DB (ISO) 4-(2,4-diklorfenoxi)smörsyra

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

2,4-DB (ISO) GHS label elements

Everything CLP Annex VI fixes for 2,4-DB (ISO), laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogramGHS09 Environment pictogram

Warning

2,4-DB (ISO)

  • Harmful if swallowed.
  • Toxic to aquatic life with long lasting effects.
  • Do not eat, drink or smoke when using this product.
  • Avoid release to the environment.
  • IF SWALLOWED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.
  • Collect spillage.
  • Dispose of contents/container to

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

Need this as an actual label? Open 2,4-DB (ISO) in the GHS label constructor →

07 · Health hazards

2,4-DB (ISO) health hazards and exposure limits

2,4-DB (ISO) hazard summary

A skin and eye irritant; The esters of 2,4-D are hydrolyzed rapidly in the body to 2,4-D; Do not accumulate in mammals; Plasma half-life is about 1 day; Analysis of 2,4-D as esters and amine salts in 1982 found the esters more highly contaminated with dioxins; [HSDB] Chlorophenoxy herbicides are possibly carcinogenic to humans (Group 2B); [IARC] See 2,3,7,8-Tetrachlorodibenzo-p-dioxin. See 2,4D.

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

2,4-DB (ISO) carcinogenicity classification

Cancer Classification: Not Likely to be Carcinogenic to Humans

Source: Hazardous Substances Data Bank (HSDB)

Classification of carcinogenicity: 1) evidence in humans: limited; Overall summary evaluation of carcinogenic risk to humans is Group 2B: The agent is possibly carcinogenic to humans. /Chlorophenoxy herbicides; From table/

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

2,4-DB (ISO) 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.

2,4-DB (ISO) melting point

Property Value Conditions Source
Melting point 119 °C (246.2 °F) range, midpoint shown HSDB

2,4-DB (ISO) solubility

Property Value Conditions Source
Solubility Readily soluble in acetone, ethanol, and diethyl ether. Slightly soluble in benzene, toluene, and kerosene. HSDB
Water solubility: 46 ppm at 25 °C. at 25 °C HSDB

2,4-DB (ISO) vapor pressure

Property Value Conditions Source
Vapor pressure 0.0000111 mmHg Haz-Map

2,4-DB (ISO) corrosivity

Property Value Conditions Source
Corrosivity The acid is slightly corrosive to iron. HSDB

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

09 · Handling and storage

2,4-DB (ISO) storage and handling

2,4-DB (ISO) incompatible materials

In an altered process to prepare 2,4-dichlorophenoxybutyric acid, the lactone /butyrolactone/ was added to the other components, and soon after, the reaction temperature reached 165 °C, higher than the usual 160 °C. Application of cooling failed to check the thermal runaway, and soon after reaching 180 °C the vessel began to fail and an explosion and fire occurred.

Source: Hazardous Substances Data Bank (HSDB)

2,4-DB (ISO) reactivity

2,4-DB is an organic acid. Neutralizes bases in exothermic reactions. Forms water soluble metal and amine salts. Hard water precipitates the calcium and magnesium salts from aqueous solutions of such salts.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 2,4-DB (ISO) in the storage compatibility matrix →

10 · Questions

2,4-DB (ISO) — frequently asked questions

What is the CAS number of 2,4-DB (ISO)?

The CAS number of 2,4-DB (ISO) is 94-82-6. Its EC number is 202-366-9.

What is the chemical formula of 2,4-DB (ISO)?

The molecular formula of 2,4-DB (ISO) is C10H10Cl2O3 and its molecular weight is 249.09 g/mol.

What does a 2,4-DB (ISO) label have to show?

Under CLP Annex VI the label for 2,4-DB (ISO) carries the pictograms Exclamation mark and Environment and the signal word is Warning.

Is 2,4-DB (ISO) flammable?

CLP Annex VI assigns 2,4-DB (ISO) 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.

Is 2,4-DB (ISO) a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for 2,4-DB (ISO). 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.

What is the melting point of 2,4-DB (ISO)?

The melting point reported for 2,4-DB (ISO) is 119 °C (246.2 °F), range, midpoint shown (HSDB).

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