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

Chlordecone

Chlordecone is crystals and is odorless.

CAS 143-50-0 C10Cl10O 490.6 g/mol Danger

01 · Identification

What Chlordecone is

Chlordecone is crystals and is odorless. Its molecular formula is C10Cl10O and its molecular weight is 490.6 g/mol. It boils at 350 °C, melts at 350 °C.

Under the GHS it carries the signal word Danger. It is classed as carcinogens.

02 · Identifiers

Chlordecone identifiers and molecular data

Chlordecone CAS number and EC number

CAS number143-50-0
EC number205-601-3
Index number (CLP Annex VI)606-019-00-6

Chlordecone molecular formula and molecular weight

Molecular formulaC10Cl10O
Molecular weight490.6 g/mol
Chemical class Carcinogens

Other names for Chlordecone

  • chlordecone (ISO)
  • perchloropentacyclo[5,3,0,02,6,03,9,04,8]decan-5-one
  • decachloropentacyclo[5,2,1,02,6,03,9,05,8]decan-4-one

03 · GHS classification

Chlordecone hazard classification

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

Chlordecone pictograms and signal word

Signal wordDanger

Chlordecone hazard class and category

GHS hazard classes Chlordecone falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 3 H301 GHS06
Acute toxicity - dermal GHS chapter 3.1 Category 3 H311 GHS06
Carcinogenicity GHS chapter 3.6 Category 2 H351 GHS08
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Chlordecone hazard statements (H-codes)

Hazard statements assigned to Chlordecone
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to Chlordecone. 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 Chlordecone

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 Chlordecone 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

Chlordecone precautionary statements

CLP Annex VI assigns 13 precautionary statements to Chlordecone. 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.

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

Chlordecone 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 хлордекон (ISO) перхлоропентацикло[5.3.0.0 2,6 .0 3,9 .0 4,8 ]декан-5-ондекахлоропентацикло[5.2.1.0 2,6 .0 3,9 .0 5,8 ]декан-4-он
Spanish español Clordecona (ISO) percloropentaciclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onadecacloropentaciclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-ona
Czech čeština chlordekon (ISO) perchlorpentacyklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-ondekachlorpentacyklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-on
Danish dansk chlordecon (ISO) perchloropentacyclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onedecachlorpentacyclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-on
German Deutsch Chlordecon (ISO) Decachlorpentacyclo(5,2,1,0 2,6 ,0 3,9 ,0 5,8 )decan-4-on
Estonian eesti kloordekoon (ISO) perkloropentatsüklo[5.3.0.0 2,6 .0 3,9 .0 4,8 ]dekaan-5-oondekakloropentatsüklo[5.2.1.0 2,6 .0 3,9 .0 5,8 ]dekaan-4-oon
Greek ελληνικά chlordecone (χλωρδεκόνη) (ISO) υπερχλωροπεντακυκλο[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]δεκαν-5-όνηδεκαχλωροπεντακυκλο[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]δεκαν-4-όνη
English English chlordecone (ISO) perchloropentacyclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onedecachloropentacyclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-one
French français chlordécone (ISO) perchloropentacyclo[5,3,0,02,6,03,9,0,4,8]décan-5-onedécachloropentacyclo[5,2,1,02,6,03,9,05,8]décan-4-one
Croatian hrvatski klordekon (ISO) perklorpentaciklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-ondekaklorpentaciklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-on
Italian italiano clordecone (ISO) percloropentaciclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onedecacloropentaciclo [5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-one
Latvian latviešu hlordekons (ISO) perhlorpentaciklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekān-5-ons dekahlorpentaciklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekān-4-ons
Lithuanian lietuvių chlordekonas (ISO) perchlorpentaciklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-onasdekachlorpentaciklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-onas
Hungarian magyar klórdekon (ISO) perklórpentaciklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekán-5-ondekaklórpentaciklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekán-4-on
Maltese Malti klorodekon (ISO) perkloropentaċiklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-ondekakloropentaċiklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-on
Dutch Nederlands chloordecone (ISO) perchloorpentacyclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decaan-5-ondecachloorpentacyclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decaan-4-on
Polish polski chlordekon (ISO) perchloropentacyklo[5,3,0,0, 2,6 ,0, 3,9 0, 4,8 ]dekan-5-ondekachloropentacyklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-on
Portuguese português clordecona (ISO) percloropentaciclo [5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onadecacloropentaciclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-ona
Romanian română clordecon (ISO) perclorpentaciclo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]decan-5-onădecacloropentaciclo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]decan-4-onă
Slovak slovenčina chlórdekón (ISO) perchlórpentacyklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ] dekan-5-ondekachlórpentacyklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ] dekan-4-on
Slovenian slovenščina klordekon (ISO) perkloropentaciklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-ondekakloropentaciklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-on
Finnish suomi klordekoni (ISO) perklooripentasyklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-onidekaklooripentasyklo[5,2,1,0 2,6 ,0 3,9 ,0 5,8 ]dekan-4-oni
Swedish svenska klordekon (ISO) perklorpentacyklo[5,3,0,0 2,6 ,0 3,9 ,0 4,8 ]dekan-5-ondekaklorpentacyklo[5,2,1,02,6,03,9,05,8]dekan-4-on

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

Chlordecone GHS label elements

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

GHS06 Skull and crossbones pictogramGHS08 Health hazard pictogramGHS09 Environment pictogram

Danger

Chlordecone

  • Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Toxic in contact with skin.
  • Toxic if swallowed.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not eat, drink or smoke when using this product.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF exposed or concerned:
  • Immediately call a POISON CENTER/doctor/
  • Get medical advice/attention.
  • Rinse mouth.
  • Wash with plenty of water/
  • Collect spillage.
  • Dispose of contents/container to

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

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

07 · Health hazards

Chlordecone health hazards and exposure limits

Chlordecone hazard summary

Mirex and chlordecone are two separate, but chemically similar, manufactured insecticides that do not occur naturally in the environment. Mirex is a white crystalline solid, and chlordecone is a tan-white crystalline solid. Both chemicals are odorless. Mirex and chlordecone have not been manufactured or used in the United States since 1978. Mirex was used to control fire ants, and as a flame retardant in plastics, rubber, paint, paper, and electrical goods from 1959 to 1972. Chlordecone was used as an insecticide on tobacco, ornamental shrubs, bananas, and citrus trees, and in ant and roach traps. Mirex was sold as a flame retardant under the trade name Dechlorane, and chlordecone was also known as Kepone. Use of trade names is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry, the Public Health Service, or the U.S. Department of Health and Human Services.

Source: Agency for Toxic Substances and Disease Registry (ATSDR)

Chlordecone carcinogenicity classification

IARC classification Group 2B — Possibly carcinogenic to humans
IARC monographs Volume 20: (1979) Some Halogenated Hydrocarbons

Studied by the US National Toxicology Program: TR-000

Classification of carcinogenicity: 1) evidence in humans: no adequate data; 2) evidence in animals: sufficient. Overall summary evaluation of carcinogenic risk to humans is Group 2B: The agent is possibly carcinogenic to humans. /From table/

Source: Hazardous Substances Data Bank (HSDB)

Kepone (chlordecone) is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.

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.

Chlordecone occupational exposure limits

US occupational exposure limits reported for Chlordecone. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL none The National Institute for Occupational Safety and Health (NIOSH)
REL Ca TWA 0.001 mg/m3 See Appendix A The National Institute for Occupational Safety and Health (NIOSH)
IDLH A potential occupational carcinogen. (NIOSH, 2024) CAMEO Chemicals
IDLH NIOSH considers kepone to be a potential occupational carcinogen. Hazardous Substances Data Bank (HSDB)
IDLH Ca [N.D.] The National Institute for Occupational Safety and Health (NIOSH)

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · Physical and chemical properties

Chlordecone 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.

Chlordecone boiling point

Property Value Conditions Source
Boiling point 350 °C (662 °F) decomposes CAMEO
Sublimes sublimes HSDB

Chlordecone melting point

Property Value Conditions Source
Melting point 350 °C (662 °F) decomp HSDB
350 °C (662 °F) sublimes NIOSH
350 °C (662 °F) decomposes CAMEO

Chlordecone density

Property Value Conditions Source
Density 1.64 g/cm³ at 25 °C HSDB
1.61 g/cm³ at 25 °C DOE PAC

Chlordecone solubility

Property Value Conditions Source
Solubility Soluble in strongly alkaline aqueous solution; readily soluble in acetone, less soluble in benzene & light petroleum HSDB
Slightly soluble in hydrocarbon solvents. Soluble in alcohols, ketones, acetic acid. HSDB
In water, 2.70 mg/L at 25 °C at 25 °C HSDB

Chlordecone vapor pressure

Property Value Conditions Source
Vapor pressure 2.25e-7 mmHg at 25 °C HSDB
3e-7 mmHg at 25 °C NIOSH
3e-7 mmHg below this value, at 25 °C CAMEO

Chlordecone flash point

Property Value Conditions Source
Flash point 100 °C (212 °F) above this value HSDB

Chlordecone lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Noncombustible Solid NIOSH

Chlordecone vapor density

Property Value Conditions Source
Vapor density 16.94 (air = 1) HSDB

Chlordecone corrosivity

Property Value Conditions Source
Corrosivity Noncorrosive HSDB

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

09 · Fire and explosion

Chlordecone fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Chlordecone fire potential

This chemical is a noncombustible solid.

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

Chlordecone storage and handling

Chlordecone safe storage

Provision to contain effluent from fire extinguishing. Separated from acids.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Chlordecone storage conditions

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

Source: Hazardous Substances Data Bank (HSDB)

Chlordecone incompatible materials

Incompatible materials: Strong oxidizing agents.

Source: Hazardous Substances Data Bank (HSDB)

Chlordecone reactivity

A halogenated ketone. Ketones are reactive with many acids and bases liberating heat and flammable gases (e.g., H2). The amount of heat may be sufficient to start a fire in the unreacted portion of the ketone. Ketones react with reducing agents such as hydrides, alkali metals, and nitrides to produce flammable gas (H2) and heat. Ketones are incompatible with isocyanates, aldehydes, cyanides, peroxides, and anhydrides. They react violently with aldehydes, HNO3, HNO3 + H2O2, and HClO4.

Source: CAMEO Chemicals

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

11 · Questions

Chlordecone — frequently asked questions

What is the CAS number of Chlordecone?

The CAS number of Chlordecone is 143-50-0. Its EC number is 205-601-3.

What is the chemical formula of Chlordecone?

The molecular formula of Chlordecone is C10Cl10O and its molecular weight is 490.6 g/mol.

What does a Chlordecone label have to show?

Under CLP Annex VI the label for Chlordecone carries the pictograms Skull and crossbones, Health hazard and Environment and the signal word is Danger.

Is Chlordecone flammable?

CLP Annex VI assigns Chlordecone 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 100 °C (212 °F), above this value (HSDB).

Is Chlordecone a carcinogen?

CLP Annex VI assigns Chlordecone H351 — suspected of causing cancer. That is category 2: the evidence points that way but is not conclusive. IARC places it in Group 2B: possibly carcinogenic to humans.

What is the exposure limit for Chlordecone?

The US occupational exposure limit reported for Chlordecone is none (The National Institute for Occupational Safety and Health (NIOSH)). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.

What is the boiling point of Chlordecone?

The boiling point reported for Chlordecone is 350 °C (662 °F), decomposes (CAMEO).

What is the melting point of Chlordecone?

The melting point reported for Chlordecone is 350 °C (662 °F), decomp (HSDB).

How should Chlordecone be stored?

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

Nearby

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