Substance profile
Methidathion
Methidathion is colorless crystals with an organophosphate odor.
01 · Identification
What Methidathion is
Methidathion is colorless crystals with an organophosphate odor. Its molecular formula is C6H11N2O4PS3 and its molecular weight is 302.3 g/mol. It melts at 39 °C.
Under the GHS it carries the signal word Danger. It is classed as carcinogens.
02 · Identifiers
Methidathion identifiers and molecular data
Methidathion CAS number and EC number
Methidathion molecular formula and molecular weight
Other names for Methidathion
- methidathion (ISO)
- 2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl-O,O-dimethylphosphorodithioate
03 · GHS classification
Methidathion hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Methidathion pictograms and signal word
Methidathion hazard class and category
| 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 4 | H312 | GHS07 |
| 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.
Methidathion hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H300 | Fatal if swallowed. |
| H312 | Harmful in contact with skin. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
This page lists only the codes assigned to Methidathion. 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 Methidathion
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 Methidathion 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
Methidathion precautionary statements
CLP Annex VI assigns 11 precautionary statements to Methidathion. 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.
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
Methidathion 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 | метидатион (ISO) 5-метокси-2,3-дихидро-2-оксо-1,3,4-тиадиазол-3-илметил- O , O -диметилов фосфородитиоат |
| Spanish español | Metidatión (ISO) fosforoditioato de 2,3-dihidro-5-metoxi-2-oxo-1,3,4-tiadiazol-3-ilmetilo y O , O -dimetilo |
| Czech čeština | methidathion (ISO) S -(5-methoxy-2(3 H )-oxo-4,5-dihydro-1,3,4-thiadiazol-3-yl)methyl- O, O -dimethyl-fosforodithioát |
| Danish dansk | methidathion (ISO) 2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl- O, O- dimethyldithiophosphat |
| German Deutsch | Methidathion (ISO) 2,3-Dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl- O, O -dimethylphosphorodithioat |
| Estonian eesti | metidatioon (ISO) 2,3-dihüdro-5-metoksü-2-okso-1,3,4-tiadiasool-3-üülmetüül- O , O -dimetüülfosforoditioaat |
| Greek ελληνικά | methidathion (μεθιδαθείο) (ISO) διθειοφωσφορικό 2,3-διυδρο-5-μεθοξυ-2-οξο-1,3,4-θειαδιαζολ-3-υλομεθυλο- O , O -διμεθύλιο |
| English English | methidathion (ISO) 2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl- O , O -dimethylphosphorodithioate |
| French français | méthidathion (ISO) 2,3-dihydro-5-méthoxy-2-oxo-1,3,4-thiadiazol-3-ylméthyl- O , O -diméthylphosphorodithioate |
| Croatian hrvatski | metidation (ISO) 2,3-dihidro-5-metoksi-2-okso-1,3,4-tiadiazol-3-il-metil- O , O -dimetil-fosforoditioat |
| Italian italiano | metidation (ISO) ditiofosfato di 2,3-diidro-5-metossi-2-osso-1,3,4-tiadiazol-3-ilmetile e O, O-dimetile |
| Latvian latviešu | metidations (ISO) 2,3-dihidro-5-metoksi-2-okso-1,3,4-tiadiazol-3-ilmetil- O , O -dimetilfosforditioāts |
| Lithuanian lietuvių | metidationas (ISO) 2,3-dihidro-5-metoksi-2-okso-1,3,4-tiadiazol-3-ilmetil- O , O -dimetilditiofosfatas |
| Hungarian magyar | metidation (ISO) 2,3-dihidro-5-metoxi-2-oxo-1,3,4-tiadiazol-3-ilmetil- O, O -dimetil-ditiofoszfát |
| Maltese Malti | metidatijon (ISO) 2,3-diidro-5-metossi-2-osso-1,3,4-tijadiażol-3-ilmetil- O , O -dimetilfosforoditijoat |
| Dutch Nederlands | methidathion (ISO) 2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazool-3-ylmethyl- O , O -dimethyldithiofosfaat |
| Polish polski | metydation (ISO) ditiofosforan S -(5-metoksy-2-okso-2,3-dihydro-1,3,4-tiadiazol-3-ilo)metylu- O , O -dimetylu |
| Portuguese português | metidatião (ISO) ditiofosfato de 2,3-di-hidro-5-metoxi-2-oxo-1,3,4-tiadiazol-3-ilmetilo e de O , O -dimetilo |
| Romanian română | metidation (ISO) ditiofosfat de 2,3- dihidro-5-metoxi-2-oxo- 1,3,4-tiadiazol-3-ilmetil și de O , O -dimetil |
| Slovak slovenčina | metidatión (ISO) S -[(5-metoxy-2-oxo-2,3-dihydro-1,3,4- tiadiazol-3-yl)metyl]- O, O -dimetylfosforoditioát |
| Slovenian slovenščina | metidation (ISO) 2,3-dihidro-5-metoksi-2-okso-1,3,4-tiadiazol-3-ilmetil- O , O -dimetilfosforoditioat |
| Finnish suomi | metidationi (ISO) 2,3-dihydro-5-metoksi-2-okso-1,3,4-tiadiatsoli-3-yylimetyyli- O , O -dimetyylifosforoditioaatti |
| Swedish svenska | metidation (ISO) 2,3-dihydro-5-metoxi-2-oxo-1,3,4-tiadiazol-3-ylmetyl- O , O -dimetylfosforditioat |
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
Methidathion GHS label elements
Everything CLP Annex VI fixes for Methidathion, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Methidathion
- Fatal if swallowed.
- Harmful in contact with skin.
- Very toxic to aquatic life.
- Very toxic to aquatic life with long lasting effects.
- 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:
- Immediately call a POISON CENTER/doctor/…
- Call a POISON CENTER/doctor/… 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 Methidathion in the GHS label constructor →
07 · Health hazards
Methidathion health hazards and exposure limits
Methidathion hazard summary
Allergic contact dermatitis reported in workers handling this pesticide; [Kanerva, p. 1812] A cholinesterase inhibitor that may cause convulsions and respiratory failure; May have cumulative effects; Can be absorbed through skin; [ICSC] Severely irritating to eyes; No reports of delayed neuropathy following ingestion poisonings; [HSDB] Human ingestion of 93 mg/kg causes miosis, lachrymation, and coma; [RTECS] A chronic dietary study of dogs produced inhibition of cholinesterase activity, increased hepatic enzymes, gross hepatic lesions, histopathology, and chronic hepatitis; [Reference #1] An irritant that may cause serious eye injury; Highly toxic by ingestion, inhalation, and skin absorption; [Aldrich MSDS] The average of two baseline respective cholinesterase activity determinations three days apart, with no exposures to enzyme inhibiting pesticides for at least 30 days, is recommended for each worker prior to exposure to cholinesterase inhibitors because of large inter-individual differences in published baseline values. To be established at least once a year. Removal from workplace exposures is recommended until the cholinesterase activity returns to within 20% of baseline. [TLVs and BEIs]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Methidathion carcinogenicity classification
Cancer Classification: Group C Possible Human Carcinogen
Source: Hazardous Substances Data Bank (HSDB)
CLASSIFICATION: C; possible human carcinogen. BASIS FOR CLASSIFICATION: Increased incidence of liver adenomas, carcinomas, and combined adenomas and carcinomas in male mice. There was no shortening of time to tumor. Short-term tests and structure/activity study were not supportive of a higher classification. HUMAN CARCINOGENICITY DATA: None. ANIMAL CARCINOGENICITY DATA: Limited.
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
Methidathion 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.
Methidathion melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 39 °C (102.2 °F) | HSDB | |
| 39.44 °C (103 °F) | range, midpoint shown | CAMEO |
Methidathion density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.5 g/cm³ | ICSC | |
| 1.51 g/cm³ | at 20 °C | HSDB | |
| 1.495 g/cm³ | at 20 °C | CAMEO |
Methidathion solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Solubility (all in g/L at 20 °C): ethanol (150); acetone (670); toluene (720); hexane (11); n-octanol (14) | at 20 °C | HSDB |
| In water, 187 mg/L at 20 °C | at 20 °C | HSDB | |
| Soluble in benzene, methanol and xylene at >60 g/100 mL at 25 °C. Moderately soluble in chloroform and dichloromethane. | at 25 °C | HSDB |
Methidathion vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 0.000001 mmHg | OSHA | |
| 0.000001 mmHg | at 20 °C | CAMEO | |
| 0.00000337 mmHg | at 25 °C | HSDB |
Methidathion flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 100 °C (212 °F) | ICSC |
Methidathion corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Non-corrosive | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Handling and storage
Methidathion storage and handling
Methidathion safe storage
Provision to contain effluent from fire extinguishing. Separated from food and feedstuffs. Well closed. Store in an area without drain or sewer access.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Methidathion storage conditions
Store in dry, well-ventilated, secure area out of reach of children and animals.
Source: Hazardous Substances Data Bank (HSDB)
Methidathion reactivity
Organophosphates, such as METHIDATHION, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Methidathion in the storage compatibility matrix →
10 · Questions
Methidathion — frequently asked questions
What is the CAS number of Methidathion?
The CAS number of Methidathion is 950-37-8. Its EC number is 213-449-4.
What is the chemical formula of Methidathion?
The molecular formula of Methidathion is C6H11N2O4PS3 and its molecular weight is 302.3 g/mol.
What does a Methidathion label have to show?
Under CLP Annex VI the label for Methidathion carries the pictograms Skull and crossbones and Environment and the signal word is Danger.
Is Methidathion flammable?
CLP Annex VI assigns Methidathion 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) (ICSC).
Is Methidathion a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Methidathion. 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 Methidathion?
The melting point reported for Methidathion is 39 °C (102.2 °F) (HSDB).
How should Methidathion be stored?
Store in dry, well-ventilated, secure area out of reach of children and animals. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Methidathion
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