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

Heptachlor

Heptachlor is a white to light tan waxy solid with a camphor-like odor.

CAS 76-44-8 C10H5Cl7 373.3 g/mol Danger

01 · Identification

What Heptachlor is

Heptachlor is a white to light tan waxy solid with a camphor-like odor. Its molecular formula is C10H5Cl7 and its molecular weight is 373.3 g/mol. It boils at 145 °C, melts at 95 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

02 · Identifiers

Heptachlor identifiers and molecular data

Heptachlor CAS number and EC number

CAS number76-44-8
EC number200-962-3
Index number (CLP Annex VI)602-046-00-2

Heptachlor molecular formula and molecular weight

Molecular formulaC10H5Cl7
Molecular weight373.3 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Heptachlor

  • heptachlor (ISO)
  • 1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene

03 · GHS classification

Heptachlor hazard classification

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

Heptachlor pictograms and signal word

Signal wordDanger

Heptachlor hazard class and category

GHS hazard classes Heptachlor 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
Specific target organ toxicity - repeated exposure GHS chapter 3.9 Category 2 H373 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

Heptachlor hazard statements (H-codes)

Hazard statements assigned to Heptachlor
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.
H373 May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to Heptachlor. 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 Heptachlor

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 Heptachlor 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

Heptachlor precautionary statements

CLP Annex VI assigns 15 precautionary statements to Heptachlor. 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

Heptachlor 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 хептахлор (ISO) 1,4,5,6,7,8,8-хептахлоро-3a,4,7,7a-тетрахидро-4,7-метаноинден
Spanish español Heptacloro (ISO) 1,4,5,6,7,8,8-heptacloro-3a,4,7,7a-tetrahidro-4,7-metanoindeno
Czech čeština heptachlor (ISO) 1,4,5,6,7,8,8-heptachlor-3a,4,7,7a-tetrahydro-1 H -4,7-methanoinden
Danish dansk heptachlor (ISO) 1,4,5,6,7,8,8-heptachlor-3a,4,7,7a-tetrahydro-4,7-methanoinden
German Deutsch Heptachlor (ISO) 1,4,5,6,7,8,8-Heptachlor-3a,4,7,7a-tetrahydro-4,7-methanoinden
Estonian eesti heptakloor (ISO) 1,4,5,6,7,8,8-heptakloro-3a,4,7,7a-tetrahüdro-4,7-metanoindeen
Greek ελληνικά heptachlor (επταχλώριο) (ISO) 1,4,5,6,7,8,8-επταχλωρο-3a,4,7,7a-τετραϋδρο-4,7-μεθανοϊνδένιο
English English heptachlor (ISO) 1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindene
French français heptachlore (ISO) 1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tétrahydro-4,7-méthanoindène
Croatian hrvatski heptaklor (ISO) 1,4,5,6,7,8,8-heptaklor-3a,4,7,7a-tetrahidro-4,7-metanoinden
Italian italiano eptacloro (ISO) 1,4,5,6,7,8,8- eptacloro - 3a,4,7,7a-tetraidro-4,7-metanoindene
Latvian latviešu heptahlors (ISO) 1,4,5,6,7,8,8-heptahlor-3a,4,7,7a-tetrahidro-4,7-metanoindēns
Lithuanian lietuvių heptachloras (ISO) 1,4,5,6,7,8,8-heptachlor-3a,4,7,7a-tetrahidro-4,7-metanoindenas
Hungarian magyar heptaklór (ISO) 1,4,5,6,7,8,8-heptaklór-3a,4,7,7a-tetrahidro-4,7-metanoindén
Maltese Malti ettaklor (ISO) 1,4,5,6,7,8,8-ettakloro-3a,4,7,7a-tetraidro-4,7-metanoinden
Dutch Nederlands heptachloor (ISO) 1,4,5,6,7,8,8-heptachloor-3a,4,7,7a-tetrahydro-4,7-methanoïndeen
Polish polski heptachlor (ISO) 1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-metanoinden
Portuguese português heptacloro (ISO) 1,4,5,6,7,8,8-heptacloro-3a,4,7,7a-tetra-hidro-4,7-metanoindeno
Romanian română heptaclor (ISO) 1,4,5,6,7,8,8-heptacloro-3a,4,7,7a-tetrahidro-4,7-metanoinden
Slovak slovenčina heptachlór (ISO) 1,4,5,6,7,8,8-heptachlór-3a,4,7,7a-tetrahydro-4,7-metanoindén
Slovenian slovenščina heptaklor (ISO) 1,4,5,6,7,8,8-heptakloro-3a,4,7,7a-tetrahidro-4,7-metanoinden
Finnish suomi heptakloori (ISO) 1,4,5,6,7,8,8-heptakloori-3a,4,7,7a-tetrahydro-4,7-metanoindeeni
Swedish svenska heptaklor (ISO) 1,4,5,6,7,8,8-heptaklor-3a,4,7,7a-tetrahydro-4,7-metanoinden

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

Heptachlor GHS label elements

Everything CLP Annex VI fixes for Heptachlor, 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

Heptachlor

  • 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.
  • May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • 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.
  • Get medical advice/attention if you feel unwell.
  • 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 Heptachlor in the GHS label constructor →

07 · Health hazards

Heptachlor health hazards and exposure limits

Heptachlor hazard summary

Heptachlor was used as an insecticide; however, nearly all registered uses of heptachlor have been canceled. Very limited information is available on the health effects of heptachlor in humans. Acute (short-term) inhalation exposure to heptachlor may result in nervous system effects, with oral studies showing gastrointestinal effects. Animal studies have reported effects on the liver and central nervous system from oral exposure. Chronic (long-term) inhalation and oral exposure by humans may be associated with neurological effects including irritability, salivation, and dizziness, while oral exposure may result in effects on the blood. Human studies are inconclusive regarding heptachlor and cancer. Animal oral studies have reported liver tumors. EPA has classified heptachlor as a Group B2, probable human carcinogen.

Source: EPA Hazardous Air Pollutants

Heptachlor carcinogenicity classification

IARC classification Group 2B — Possibly carcinogenic to humans
IARC monographs Volume 53: (1991) Occupational Exposures in Insecticide Application, and Some Pesticides; Volume 79: (2001) Some Thyrotropic Agents

Studied by the US National Toxicology Program: TR-009: Bioassay of Heptachlor for Possible Carcinogenicity (CASRN 76-44-8) (1977 )

Evaluation: There is inadequate evidence in humans for the carcinogenicity of chlordane and heptachlor. There is sufficient evidence in experimental animals for the carcinogenicity of chlordane and heptachlor. Overall evaluation: Chlordane and heptachlor are possibly carcinogenic to humans (Group 2B).

Source: Hazardous Substances Data Bank (HSDB)

Cancer Classification: Group B2 Probable Human Carcinogen

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.

Heptachlor occupational exposure limits

US occupational exposure limits reported for Heptachlor. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL 0.5 [mg/m3] Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
PEL 0.5 mg/m³ Occupational Safety and Health Administration (OSHA)
PEL TWA 0.5 mg/m3 [skin] The National Institute for Occupational Safety and Health (NIOSH)
REL 0.5 mg/m³ Occupational Safety and Health Administration (OSHA)
REL Ca TWA 0.5 mg/m3 [skin] See Appendix A The National Institute for Occupational Safety and Health (NIOSH)
IDLH 35 mg/m3 ; A potential occupational carcinogen. (NIOSH, 2024) CAMEO Chemicals
IDLH 35.0 [mg/m3] Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
IDLH NIOSH considers heptachlor to be a potential occupational carcinogen. [35 mg/cu m] Hazardous Substances Data Bank (HSDB)

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

Heptachlor 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.

Heptachlor boiling point

Property Value Conditions Source
Boiling point 145 °C (293 °F) decomposes NIOSH
145 °C (293 °F) at 1.5 mmHg (reduced pressure) HSDB

Heptachlor melting point

Property Value Conditions Source
Melting point 95 °C (203 °F) NIOSH
95.5 °C (203.9 °F) DOE PAC

Heptachlor density

Property Value Conditions Source
Density 1.66 g/cm³ NIOSH
1.6 g/cm³ ICSC
1.66 g/cm³ at 20 °C CAMEO

Heptachlor solubility

Property Value Conditions Source
Solubility Soluble in hexane. HSDB
Soluble in ethyl ether, ethanol, ligroin HSDB
g/100 ml solvent @ 27 °C: acetone 75, benzene 106, carbon tetrachloride 112, cyclohexanone 119, alcohol 4.5, xylene 102 at 27 °C HSDB

Heptachlor vapor pressure

Property Value Conditions Source
Vapor pressure 0.0004 mmHg at 25 °C HSDB
0.0003 mmHg at 25 °C NIOSH

Heptachlor lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Heptachlor is not combustible, but may be dissolved in flammable liquids. HSDB
Noncombustible Solid, but may be dissolved in flammable liquids. NIOSH

Heptachlor odor threshold

Property Value Conditions Source
Odor threshold 0.02 PPM HSDB

Heptachlor corrosivity

Property Value Conditions Source
Corrosivity Corrosive to metals. HSDB

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

09 · Fire and explosion

Heptachlor 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.

Heptachlor fire potential

Non-combustible

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

Heptachlor storage and handling

Heptachlor safe storage

Provision to contain effluent from fire extinguishing. Separated from strong oxidants, metals and food and feedstuffs. Well closed. Keep in a well-ventilated room. Dry. Store in an area without drain or sewer access.

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

Heptachlor storage conditions

Protect containers against physical damage. Outdoor or detached storage is preferred; in case of indoor storage, cool, well-ventilated, fire-proof place should be used and kept away from source of ignition.

Source: Hazardous Substances Data Bank (HSDB)

Heptachlor incompatible materials

Heptachlor can react with iron and rust to form ... hydrogen chloride gas.

Source: Hazardous Substances Data Bank (HSDB)

Heptachlor reactivity

HEPTACHLOR is incompatible with strong alkalis. Corrosive to metals. Can react with iron and rust to form toxic gases. Can react vigorously with oxidizing materials. Susceptible to epoxidation (NTP, 1992).

Source: CAMEO Chemicals

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

11 · Questions

Heptachlor — frequently asked questions

What is the CAS number of Heptachlor?

The CAS number of Heptachlor is 76-44-8. Its EC number is 200-962-3.

What is the chemical formula of Heptachlor?

The molecular formula of Heptachlor is C10H5Cl7 and its molecular weight is 373.3 g/mol.

What does a Heptachlor label have to show?

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

Is Heptachlor flammable?

CLP Annex VI assigns Heptachlor 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 Heptachlor a carcinogen?

CLP Annex VI assigns Heptachlor 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 Heptachlor?

The US occupational exposure limit reported for Heptachlor is 0.5 [mg/m3] (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). 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 Heptachlor?

The boiling point reported for Heptachlor is 145 °C (293 °F), decomposes (NIOSH).

What is the melting point of Heptachlor?

The melting point reported for Heptachlor is 95 °C (203 °F) (NIOSH).

How should Heptachlor be stored?

Protect containers against physical damage. Outdoor or detached storage is preferred; in case of indoor storage, cool, well-ventilated, fire-proof place should be used and kept away from source of ignition. (Hazardous Substances Data Bank (HSDB))

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