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

Methylmercury chloride

Methylmercury chloride is white crystals or plates from ethanol with a characteristic odor.

CAS 115-09-3 Danger

01 · Identification

What Methylmercury chloride is

Methylmercury chloride is white crystals or plates from ethanol with a characteristic odor. It melts at 170 °C.

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

02 · Identifiers

Methylmercury chloride identifiers and molecular data

Methylmercury chloride CAS number and EC number

CAS number115-09-3
EC number204-064-2
Index number (CLP Annex VI)080-012-00-0

Methylmercury chloride molecular formula and molecular weight

Chemical class Carcinogens

Other names for Methylmercury chloride

  • methylmercuric chloride

03 · GHS classification

Methylmercury chloride hazard classification

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

Methylmercury chloride pictograms and signal word

Signal wordDanger

Methylmercury chloride hazard class and category

GHS hazard classes Methylmercury chloride falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 1 or 2 H300 GHS06
Acute toxicity - dermal GHS chapter 3.1 Category 1 or 2 H310 GHS06
Acute toxicity - inhalation GHS chapter 3.1 Category 1 or 2 H330 GHS06
Carcinogenicity GHS chapter 3.6 Category 2 H351 GHS08
Reproductive toxicity GHS chapter 3.7 Category Lactation H362
Specific target organ toxicity - repeated exposure GHS chapter 3.9 Category 1 H372 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

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

Methylmercury chloride hazard statements (H-codes)

Hazard statements assigned to Methylmercury chloride
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>.
H360Df May damage the unborn child. Suspected of damaging fertility.
H362 May cause harm to breast-fed children.
H330 Fatal if inhaled.
H310 Fatal in contact with skin.
H300 Fatal if swallowed.
H372 Causes 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 Methylmercury chloride. 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 Methylmercury chloride

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 Methylmercury chloride 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

Methylmercury chloride precautionary statements

CLP Annex VI assigns 17 precautionary statements to Methylmercury chloride. 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

Methylmercury chloride 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 метилживачен хлорид
Spanish español Cloruro de metilmercurio
Czech čeština chlorid methylrtuti
Danish dansk methylkviksølvchlorid
German Deutsch Methylquecksilberchlorid
Estonian eesti metüülelavhõbekloriid
Greek ελληνικά χλωριούχος μεθυλυδράργυρος
English English methylmercuric chloride
French français chlorure de méthylmercure
Croatian hrvatski metilživin klorid
Italian italiano metilmercurio cloruro
Latvian latviešu metildzīvsudraba hlorīds
Lithuanian lietuvių metilgyvsidabrio chloridas
Hungarian magyar metil-higany-klorid
Maltese Malti klorur metilmerkuriku
Dutch Nederlands methylkwikchloride
Polish polski chlorek metylortęci
Portuguese português cloreto metilmercúrico
Romanian română clorură de metilmercur
Slovak slovenčina metylhydrargýrium-chlorid
Slovenian slovenščina metilživosrebrov klorid
Finnish suomi Metyylielohopeakloridi
Swedish svenska metylkvicksilverklorid

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

Methylmercury chloride GHS label elements

Everything CLP Annex VI fixes for Methylmercury chloride, 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

Methylmercury chloride

  • Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • May damage the unborn child. Suspected of damaging fertility.
  • May cause harm to breast-fed children.
  • Fatal if inhaled.
  • Fatal in contact with skin.
  • Fatal if swallowed.
  • Causes 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.
  • Use only outdoors or in a well-ventilated area.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • 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 Methylmercury chloride in the GHS label constructor →

07 · Health hazards

Methylmercury chloride health hazards and exposure limits

Methylmercury chloride hazard summary

May cause CNS injury and death; [CAMEO] May be fatal by inhalation, skin absorption, or ingestion; May cause irritation; Targets nerves; [MSDSonline] See Mercury, alkyl compounds and linked occupational diseases.

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

Methylmercury chloride carcinogenicity classification

Methylmercury compounds are possibly carcinogenic to humans (Group 2B). There is sufficient evidence in experimental animals for the carcinogenicity of methylmercury chloride. /Methylmercury compounds/

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.

Methylmercury chloride occupational exposure limits

US occupational exposure limits reported for Methylmercury chloride. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL 0.01 [mg/m3], Ceiling(OSHA) = 0.04 mg/m3, as Hg Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
IDLH 2 mg Hg/m3 (NIOSH, 2024) CAMEO Chemicals
IDLH 2.0 [mg/m3], as Hg Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

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

Methylmercury chloride 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.

Methylmercury chloride melting point

Property Value Conditions Source
Melting point 170 °C (338 °F) HSDB

Methylmercury chloride density

Property Value Conditions Source
Density 4.063 g/cm³ HSDB
4.06 g/cm³ at 25 °C CAMEO

Methylmercury chloride solubility

Property Value Conditions Source
Solubility less than 0.1 mg/mL at 70 °F (NTP, 1992) at 21.11 °C CAMEO

Methylmercury chloride vapor pressure

Property Value Conditions Source
Vapor pressure 0.0085 mmHg CAMEO
0.0085 mmHg at 25 °C HSDB

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

09 · Source notes

Further notes on Methylmercury chloride

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.

Solubility

METHYL- & ETHYLMERCURY CHLORIDE HAVE A HIGH SOLUBILITY IN SOLVENTS & LIPIDS; SHORT-CHAIN ALKYLMERCURIC COMPOUNDS FORM SALTS WITH HALOGENS, WHICH ARE HIGHLY VOLATILE AT ROOM TEMP; SATURATION CONCN OF METHYLMERCURY CHLORIDE AT 20 °C IS 90000 MG MERCURY/CU M; OTHER SALTS, SUCH AS HYDROXIDE & NITRATE OF METHYLMERCURY ARE LESS VOLATILE /METHYLMERCURY COMPOUNDS/

Source: HSDB

10 · Handling and storage

Methylmercury chloride storage and handling

Methylmercury chloride storage conditions

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Source: Hazardous Substances Data Bank (HSDB)

Methylmercury chloride reactivity

METHYL MERCURY(II)CHLORIDE may be sensitive to light.

Source: CAMEO Chemicals

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

11 · Questions

Methylmercury chloride — frequently asked questions

What is the CAS number of Methylmercury chloride?

The CAS number of Methylmercury chloride is 115-09-3. Its EC number is 204-064-2.

What does a Methylmercury chloride label have to show?

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

Is Methylmercury chloride flammable?

CLP Annex VI assigns Methylmercury chloride 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 Methylmercury chloride a carcinogen?

CLP Annex VI assigns Methylmercury chloride H351 — suspected of causing cancer. That is category 2: the evidence points that way but is not conclusive.

What is the exposure limit for Methylmercury chloride?

The US occupational exposure limit reported for Methylmercury chloride is 0.01 [mg/m3], Ceiling(OSHA) = 0.04 mg/m3, as Hg (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 melting point of Methylmercury chloride?

The melting point reported for Methylmercury chloride is 170 °C (338 °F) (HSDB).

How should Methylmercury chloride be stored?

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/ (Hazardous Substances Data Bank (HSDB))

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