Browse history interactively

Page 1

Page 1Revision 1

Page 2

Page 2Revision 2

← Previous editContent deleted Content addedVisualWikitext

Revision as of 09:20, 24 October 2011 editBeetstra (talk | contribs)Edit filter managers, Administrators172,031 edits Script assisted update of identifiers for the Chem/Drugbox validation project (updated: 'ChEMBL').← Previous edit		Latest revision as of 17:00, 31 December 2024 edit undoMimirIsSmart (talk | contribs)Extended confirmed users4,986 edits CheckedTag: Visual edit
(148 intermediate revisions by 89 users not shown)
Line 1:		Line 1:
	{{Use mdy dates|date=February 2011}}		{{Use mdy dates|date=January 2025}}{{chembox
			| Watchedfields = changed
	{{chembox
	| verifiedrevid = 444471153		| verifiedrevid = 457117816
			| ImageFile = Methyl iodide.svg
	| ImageFile_Ref = {{chemboximage|correct|??}}		| ImageFile_Ref = {{chemboximage|correct|??}}
			| ImageSize = 100
	| ImageFile = Methyl-iodide-CRC-MW-IR-dimensions-2D.png
			| ImageName = Stereo skeletal formula of iodomethane with all explicit hydrogens added
	| ImageSize = 150px
	| ImageFile1 = Iodomethane-3D-vdW.png		| ImageFileL1 = Iodomethane-3D-balls.png
			| ImageFileL1_Ref = {{chemboximage|correct|??}}
	| ImageSize1 = 130px
			| ImageNameL1 = Ball and stick model of iodomethane
	| IUPACName = Iodomethane
			| ImageFileR1 = Iodomethane-3D-vdW.png
	| OtherNames = Monoiodomethane, Methyl iodine, MeI, Halon 10001, UN 2644
			| ImageFileR1_Ref = {{chemboximage|correct|??}}
	| Section1 = {{Chembox Identifiers
			| ImageNameR1 = Spacefill model of iodomethane
	| CASNo = 74-88-4
			| PIN = Iodomethane<ref name=iupac2013>{{cite book | title = Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book) | publisher = ] | date = 2014 | location = Cambridge | page = 657 | doi = 10.1039/9781849733069-FP001 | isbn = 978-0-85404-182-4| chapter = Front Matter }}</ref>
	| CASNo_Ref = {{cascite|correct|CAS}}
			| OtherNames = {{Unbulleted list
	| EINECS = 200-819-5
			| Methyl iodide<ref name=iupac2013 />
	| ChEMBL = 115849
			| Methyl iodine
			| Monoiodomethane
			}}
			|Section1={{Chembox Identifiers
			| Abbreviations = {{Unbulleted list
			| Halon 10001
			| MeI
			}}
			| CASNo = 74-88-4
			| CASNo_Ref = {{cascite|correct|CAS}}
			| UNII_Ref = {{fdacite|correct|FDA}}
			| UNII = DAT010ZJSR
	| PubChem = 6328		| PubChem = 6328
	| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
	| ChemSpiderID = 6088		| ChemSpiderID = 6088
	| ChEBI_Ref = {{ebicite|correct|EBI}}		| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
			| EINECS = 200-819-5
			| UNNumber = 2644
			| KEGG = C18448
			| KEGG_Ref = {{keggcite|correct|kegg}}
			| MeSHName = methyl+iodide
	| ChEBI = 39282		| ChEBI = 39282
			| ChEBI_Ref = {{ebicite|correct|EBI}}
			| ChEMBL = 115849
			| ChEMBL_Ref = {{ebicite|correct|EBI}}
			| RTECS = PA9450000
			| Beilstein = 969135
			| Gmelin = 1233
	| SMILES = CI		| SMILES = CI
			| StdInChI = 1S/CH3I/c1-2/h1H3
	| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
			| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
	| StdInChI=1S/CH3I/c1-2/h1H3
	| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
	| StdInChIKey = INQOMBQAUSQDDS-UHFFFAOYSA-N		| StdInChIKey = INQOMBQAUSQDDS-UHFFFAOYSA-N
			| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
	| RTECS = PA9450000
			}}
	| KEGG_Ref = {{keggcite|correct|kegg}}
			|Section2={{Chembox Properties
	| KEGG = C18448
			| C=1 | H=3 | I=1
	}}
			| Appearance = Colorless liquid
	| Section2 = {{Chembox Properties
			| Odor = Pungent, ]-like<ref name=PGCH/>
	| Formula = CH<sub>3</sub>I
			| Density = 2.28{{nbsp}}g·mL<sup>−1</sup>
	| MolarMass = 141.94 g/mol
			| MeltingPtK = 206.7
	| Appearance = Clear colourless liquid with acrid odor
			| BoilingPtK = 315.5 to 315.9
	| Density = 2.28 g/cm<sup>3</sup> (20 °C)<ref name=Merck>'']'', 11th Edition, '''6002'''</ref>
			| Solubility = 14{{nbsp}}g·L<sup>−1</sup> (at {{convert|20|C|disp=comma}})<ref name=GESTIS>{{GESTIS|ZVG=28110}}</ref>
	| MeltingPtC = -66.45
	| BoilingPtC = 42.43		| LogP = 1.609
			| VaporPressure = 54.4{{nbsp}}kPa (at {{convert|20|C|disp=comma}})
	| Solubility = 1.4 g/100 mL (20 °C)
	| LogP = 1.51		| RefractIndex = 1.530–1.531
			| HenryConstant = 1.4{{nbsp}}μmol·Pa<sup>−1</sup>·kg<sup>−1</sup>
	| VaporPressure = 50 kPa at 20 °C <br>53.32 at 25.3 °C <br>166.1 kPa at 55 °C
			| MagSus = −57.2·10<sup>−6</sup> cm<sup>3</sup>·mol{{sup|−1}}
	| RefractIndex = 1.531
	}}		}}
	| Section3 = {{Chembox Structure		|Section3={{Chembox Structure
	| MolShape = Tetrahedral		| MolShape = Tetrahedron
	}}		}}
	| Section3 = {{Chembox Hazards		|Section4={{Chembox Thermochemistry
			| DeltaHf = −14.1 – −13.1{{nbsp}}kJ·mol<sup>−1</sup>
	| EUClass = Toxic ('''T'''), ]
			| DeltaHc = −808.9 – −808.3{{nbsp}}kJ·mol<sup>−1</sup>
	| ExternalMSDS =
			| HeatCapacity = 82.75{{nbsp}}J·K<sup>−1</sup>·mol<sup>−1</sup>
	| FlashPt =
			}}
	| Autoignition =
			|Section5={{Chembox Hazards
	| NFPA-H = 3
			| GHSPictograms = {{gHS skull and crossbones}} {{gHS health hazard}}
	| NFPA-F = 1
			| GHSSignalWord = '''DANGER'''
	| NFPA-R = 1
			| HPhrases = {{h-phrases|301|312|315|331|335|351}}
	| NFPA-O =
			| PPhrases = {{p-phrases|261|280|301+310|311}}
	| RPhrases = {{R21}} {{R23/25}} {{R37/38}} {{R40}}
			| NFPA-H = 3
	| SPhrases = {{S1/2}} {{S36/37}} {{S38}} {{S45}}
			| NFPA-F = 0
	| ExploLimits = 8.5 - 66%
			| NFPA-R = 0
	| LD50 = 0.78 mmol/kg (mouse, ])<ref name=Merck/>
			| LD50 = {{unbulleted list
	| TLV-TWA = 2 ppm
			| 76{{nbsp}}mg·kg<sup>−1</sup> <small>(oral, rat)</small><ref name=GESTIS/>
	| TLV-STEL = 5 ppm
			| 800{{nbsp}}mg·kg<sup>−1</sup> <small>(dermal, guinea pig)</small>
	}}
			}}
			| IDLH = Ca <ref name=PGCH>{{PGCH|0420}}</ref>
			| PEL = TWA 5{{nbsp}}ppm (28{{nbsp}}mg/m<sup>3</sup>) <ref name=PGCH/>
			| REL = Ca TWA 2{{nbsp}}ppm (10{{nbsp}}mg/m<sup>3</sup>) <ref name=PGCH/>
			| LC50 = {{ubl
			| 1550{{nbsp}}ppm (rat, 30{{nbsp}}min)
			| 860{{nbsp}}ppm (mouse, 57{{nbsp}}min)
			| 220{{nbsp}}ppm (rat, 4{{nbsp}}hr)<ref name=IDLH>{{IDLH|74884|Methyl iodide}}</ref>
			}}
			| LCLo = 3800{{nbsp}}ppm (rat, 15{{nbsp}}min)<ref name=IDLH/>
			}}
			|Section6={{Chembox Related
			| OtherFunction_label = iodomethanes
			| OtherFunction = {{unbulleted list|]|]|]|]}}
			}}
	}}		}}
	'''Methyl iodide''', also called '''iodomethane''', and commonly abbreviated "MeI", is the ] with the formula CH<sub>3</sub>I. It is a ], colorless, ] liquid. In terms of chemical structure, it is related to ] by replacement of one ] atom by an atom of ]. It is naturally emitted by ] plantations in small amounts.<ref>{{cite journal| title = Emissions of Methyl Halides and Methane from Rice Paddies| author = K. R. Redeker, N.-Y. Wang, J. C. Low, A. McMillan, S. C. Tyler, and R. J. Cicerone| journal = ] | volume = 290		'''Iodomethane''', also called '''methyl iodide''', and commonly abbreviated "MeI", is the ] with the formula CH<sub>3</sub>I. It is a ], colorless, ] liquid. In terms of chemical structure, it is related to ] by replacement of one ] atom by an atom of ]. It is naturally emitted in small amounts by ] plantations.<ref>{{cite journal| title = Emissions of Methyl Halides and Methane from Rice Paddies|author1=K. R. Redeker |author2=N.-Y. Wang |author3=J. C. Low |author4=A. McMillan |author5=S. C. Tyler |author6=R. J. Cicerone |name-list-style=amp | journal = ] | volume = 290
	| issue = 5493| pages = 966–969| year = 2000| doi = 10.1126/science.290.5493.966| pmid = 11062125}}</ref> It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans and in lesser amounts on land due to terrestrial fungi and bacteria. Methyl iodide is used in ] as a source of ]s, and was approved for use as a ] by the ] in 2007.<ref name="sfgate.com">Zitto, Kelly {{cite news | url = http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/12/01/BAOQ1GKKKN.DTL | title = Methyl iodide gains state OK for use on crops | work = ] | date = December 2, 2010}}</ref> Iodomethane is a pre-plant biocide used to control insects, plant parasitic nematodes, soil borne pathogens, and weed seeds. The compound is registered for use as a preplant soil treatment for field grown strawberries, peppers, tomatoes, stone fruits, tree nuts, grape vines, ornamentals and turf and nursery grown strawberries, stone fruits, tree nuts, and conifer trees.		| issue = 5493| pages = 966–969| year = 2000| doi = 10.1126/science.290.5493.966| pmid = 11062125|bibcode=2000Sci...290..966R |s2cid=2830653 |url=http://www.escholarship.org/uc/item/3kh8g63d }}</ref> It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans, and in lesser amounts on land by terrestrial fungi and bacteria. It is used in ] as a source of ]s.
	==Preparation and handling==		==Preparation and handling==
	Methyl iodide is formed via the ] that occurs when ] is added to a mixture of ] with red ].<ref name=king>{{OrgSynth | author = King, C. S.; Hartman, W. W. | title = Methyl Iodide | collvol = 2 | collvolpages = 399 | year = 1943 | prep =CV2P0399}}</ref> The iodinating reagent is ] that is formed ''in situ:''		Iodomethane is formed via the ] that occurs when ] is added to a mixture of ] with red ].<ref name=king>{{OrgSynth | author = King, C. S. | author2 = Hartman, W. W. | title = Methyl Iodide | collvol = 2 | collvolpages = 399 | year = 1943 | prep =CV2P0399}}</ref> The iodinating reagent is ] that is formed ''in situ:''
	:3 ] + PI<Sub>3</sub> → 3 CH<sub>3</sub>I + ]		:3 ] + PI<Sub>3</sub> → 3 CH<sub>3</sub>I + ]
	Alternatively, it is prepared from the reaction of ] with potassium iodide in the presence of ]:<ref name=king/>		Alternatively, it is prepared from the reaction of ] with potassium iodide in the presence of ]:<ref name=king/>
	:] + ] &rarr; CH<sub>3</sub>I + CH<sub>3</sub>OSO<sub>2</sub>OK		:] + ] → CH<sub>3</sub>I + CH<sub>3</sub>OSO<sub>2</sub>OK
	Methyl iodide can also be prepared by the reaction of methanol with potassium iodide, catalyzed by acid:		Iodomethane can also be prepared by the reaction of methanol with aqueous ]:
	:CH<sub>3</sub>OH + KI + H<sub>2</sub>SO<sub>4</sub> &rarr; CH<sub>3</sub>I + K<sub>2</sub>SO<sub>4</sub> + H<sub>2</sub>O		: CH<sub>3</sub>OH + HI → CH<sub>3</sub>I + H<sub>2</sub>O
	The reaction is carried out at low temperature and the water generated in the reaction is trapped by excess sulfuric acid so the reaction is not reversible. The generated methyl iodide can be distilled from the reaction mixture.		The generated iodomethane can be distilled from the reaction mixture.
			Iodomethane may also be prepared by treating ] with ] and ] under 95% ].<ref>{{Cite journal | doi=10.1021/ed010p747|title = Preparation of methyl or ethyl iodide from iodoform| journal=Journal of Chemical Education| volume=10| issue=12| pages=747|year = 1933|last1 = Kimball|first1 = R. H.|bibcode = 1933JChEd..10..747K}}</ref>
			In the ] iodomethane is formed as an intermediate product by a catalytic reaction between ] and ].
	===Storage and purification===		===Storage and purification===
	Like many organoiodide compounds, methyl iodide is typically stored in dark bottles to inhibit degradation cause by light to give iodine, giving degraded samples a purplish tinge. Commercial samples may be stabilized by copper or silver wire.<ref name = sulikowski/> It can be purified by distillation followed by washing with ] to remove iodine.		Like many organoiodide compounds, iodomethane is typically stored in dark bottles to inhibit degradation caused by light to give iodine, giving degraded samples a purplish tinge. Commercial samples may be stabilized by copper or silver wire.<ref name = sulikowski/> It can be purified by washing with ] to remove iodine followed by distillation.
			===Biogenic iodomethane===
			Most iodomethane is produced by microbial methylation of iodide. Oceans are the major source, but rice paddies are also significant.<ref>{{cite journal|journal=Int. J. Environ. Sci. Technol.|year=2017|pages=1355–1370|doi=10.1007/s13762-016-1219-5|title=REVIEW: Halocarbon Emissions from Marine Phytoplankton and Climate Change|first1=Y.-K.|last1=Lim|first2=S.-M.|last2=Phang|first3=N. Abdul |last3=Rahman|first4=W. T.|last4=Sturges|first5= G.|last5=Malin|s2cid=99300836}}</ref>
			==Reactions==
	== Reactions ==
	===Methylation reagent===		===Methylation reagent===
	Methyl iodide is an excellent substrate for S<sub>N</sub>2 substitution reactions. It is ] open for attack by ]s, and ] is a good ]. It is used for alkylating carbon, oxygen, sulfur, nitrogen, and phosphorus nucleophiles.<ref name = sulikowski>{{cite encyclopedia | encyclopedia = ] | last1 = Sulikowski | first1 = Gary A. | last2 = Sulikowski | first2 = Michelle M. | last3 = Haukaas | first3 = Michael H. | last4 = Moon | first4 = Bongjin | title = Iodomethane | year = 2005 | doi = 10.1002/047084289X.ri029m.pub2}}</ref> Unfortunately, it has a high equivalent weight: one mole of methyl iodide weighs almost three times as much as one mole of ]. On the other hand, methyl chloride and ] are gaseous, thus harder to handle; they are also weaker alkylating agents.		Iodomethane is an excellent substrate for ] reactions. It is ] open for attack by ]s, and ] is a good ]. It is used for alkylating carbon, oxygen, sulfur, nitrogen, and phosphorus nucleophiles.<ref name = sulikowski>{{cite encyclopedia | encyclopedia = ] | last1 = Sulikowski | first1 = Gary A. | title = Encyclopedia of Reagents for Organic Synthesis | last2 = Sulikowski | first2 = Michelle M. | last3 = Haukaas | first3 = Michael H. | last4 = Moon | first4 = Bongjin | year = 2005 | doi = 10.1002/047084289X.ri029m.pub2| isbn = 978-0471936237 | chapter = Iodomethane }}</ref> Unfortunately, it has a high equivalent weight: one mole of iodomethane weighs almost three times as much as one mole of ] and nearly 1.5 times as much as one mole of ]. On the other hand, ] and ] are gaseous, thus harder to handle, and are also weaker alkylating agents. Iodide can act as a catalyst when reacting chloromethane or bromomethane with a nucleophile while iodomethane is formed in ''situ''.
	Iodides are generally expensive relative to the more common chlorides and bromides, though methyl iodide is reasonably affordable; on a commercial scale, the more toxic ] is preferred, since it is both cheap and liquid. The iodide leaving group in methyl iodide may cause side reactions, as it is a powerful nucleophile. Finally, being highly reactive, methyl iodide is more dangerous for laboratory workers than related chlorides and bromides.		Iodides are generally expensive relative to the more common chlorides and bromides, though iodomethane is reasonably affordable; on a commercial scale, the more toxic ] is preferred, since it is cheap and has a higher boiling point. The iodide leaving group in iodomethane may cause unwanted side reactions. Finally, being highly reactive, iodomethane is more dangerous for laboratory workers than related chlorides and bromides.
	For example, it can be used for the methylation of ]s or ]s:<ref>{{cite journal		For example, it can be used for the methylation of ]s or ]:<ref>{{cite journal
	| title = Efficient methylation of carboxylic acids with potassium hydroxide/methyl sulfoxide and iodomethane		| title = Efficient methylation of carboxylic acids with potassium hydroxide/methyl sulfoxide and iodomethane
	| author = Avila-Zárraga, J. G., Martínez, R.		| author = Avila-Zárraga, J. G.
			| author2 = Martínez, R.
	| journal = ]		| journal = ]
	| volume = 31		| volume = 31
	| issue = 14		| issue = 14
	| pages = 2177–2183		| pages = 2177–2183
	| month = January | year = 2001		| date=January 2001
	| doi = 10.1081/SCC-100104469}}</ref>		| doi = 10.1081/SCC-100104469| s2cid = 94476899
			}}</ref>
	:]		:]
	In these examples, the ] (] or ]) removes the acidic proton to form the carboxylate or phenoxide anion, which serves as the nucleophile in the S<sub>N</sub>2 substitution.		In these examples, the ] (] or ]) removes the acidic proton to form the ] or ] anion, which serves as the nucleophile in the S<sub>N</sub>2 substitution.
	Iodide is a ] anion which means that methylation with MeI tends to occur at the "softer" end of an ambidentate ]. For example, reaction with ] ion favours attack at {{Sulfur}} rather than "hard" {{Nitrogen}}, leading mainly to ] (CH<sub>3</sub>SCN) rather than CH<sub>3</sub>NCS. This behavior is relevant to the ] of stabilized ]s such as those derived from 1,3-dicarbonyl compounds. Methylation of these and related enolates can occur on the harder ] atom or the (usually desired) carbon atom. With methyl iodide, C-alkylation nearly always predominates.		Iodide is a ] anion which means that methylation with MeI tends to occur at the "softer" end of an ambidentate ]. For example, reaction with ] ion favours attack at sulfur rather than "hard" nitrogen, leading mainly to ] (CH<sub>3</sub>SCN) rather than ] CH<sub>3</sub>NCS. This behavior is relevant to the ] of stabilized ]s such as those derived from 1,3-dicarbonyl compounds. Methylation of these and related enolates can occur on the harder ] atom or the (usually desired) carbon atom. With iodomethane, C-alkylation nearly always predominates.
	===Other reactions===		===Other reactions===
	In the ], MeI forms ''in situ'' from the reaction of ] and ]. The CH<sub>3</sub>I then reacts with ] in the presence of a ] complex to form ], the precursor to ] after ]. Most acetic acid is prepared by this method.		In the ] and the ], MeI forms ''in situ'' from the reaction of ] and ]. The CH<sub>3</sub>I then reacts with ] in the presence of a ] or ] complex to form ], the precursor to ] after ]. The Cativa process is usually preferred because less water is required to use and there are less byproducts.
	MeI is used to prepare the ], ] ("MeMgI"), a common source of "Me<sup>&minus;</sup>. The use of MeMgI has been somewhat superseded by the commercially available ]. MeI can also be used to prepare ], by reacting 2 moles of MeI with a 2/1-molar sodium ] (2 moles of sodium, 1 mol of mercury).		MeI is used to prepare the ], ] ("MeMgI"), a common source of "Me<sup>&minus;</sup>". The use of MeMgI has been somewhat superseded by the commercially available ]. MeI can also be used to prepare ], by reacting 2 moles of MeI with a 2/1-molar sodium ] (2 moles of sodium, 1&nbsp;mol of mercury).
			Iodomethane and other organic iodine compounds do form under the conditions of a serious nuclear accident,<ref>{{cite journal|doi=10.1080/23312009.2015.1049111 | volume=1 | title=An introduction to serious nuclear accident chemistry | year=2015 | journal=Cogent Chemistry | first1 = Mark Russell | last1 = St. John Foreman| doi-access=free }}</ref> after both ] and ], ] was detected in organic iodine compounds in Europe<ref>{{cite journal |doi=10.1080/10256016.2013.828717 |title=Fission products from the damaged Fukushima reactor observed in Hungary |year=2014 |last1=Bihari |first1=Árpád |last2=Dezső |first2=Zoltán |last3=Bujtás |first3=Tibor |last4=Manga |first4=László |last5=Lencsés |first5=András |last6=Dombóvári |first6=Péter |last7=Csige |first7=István |last8=Ranga |first8=Tibor |last9=Mogyorósi |first9=Magdolna |last10=Veres |first10=Mihály |journal=Isotopes in Environmental and Health Studies |volume=50 |issue=1 |pages=94–102 |pmid=24437973 |s2cid=8992460 |url=http://real.mtak.hu/21034/1/ArpadBihari_4b_TF_manuscript_revised_forREAL.pdf }}</ref> and Japan<ref>{{cite journal |doi=10.1016/0265-931X(88)90042-2|title=Physicochemical speciation of airborne 131I in Japan from Chernobyl|year=1988|last1=Noguchi|first1=Hiroshi|last2=Murata|first2=Mikio|journal=Journal of Environmental Radioactivity|volume=7|pages=65–74}}</ref> respectively.
	== Use as a pesticide ==
	Methyl iodide has also been proposed for use as a ], ], ], ], and as a soil disinfectant, replacing methyl bromide (also known as ]) (banned under the ]). Manufactured by ] and sold under the brand name MIDAS, methyl iodide is registered as a pesticide in the U.S., Mexico, Morocco, Japan, Turkey, and New Zealand and registration is pending in Australia, Guatemala, Costa Rica, Chile, Egypt, Israel, South Africa and other countries.<ref>{{cite news | url = http://finance.yahoo.com/news/Iodomethane-Approved-in-bw-422120383.html?x=0 | title = Iodomethane Approved in Mexico and Morocco | work = ] | date = October 25, 2010}}</ref> In September 2007, 54 chemists and physicians contacted the EPA expressing deep concerns of serious risk if methyl iodide were to be permitted for use in agriculture. In a letter to the EPA they stated: "We are skeptical of U.S. EPA’s conclusion that the high levels of exposure to methyl iodide that are likely to result from broadcast applications are “acceptable” risks. U.S. EPA has made many assumptions about toxicology and exposure in the risk assessment that have not been examined by independent scientific peer reviewers for adequacy or accuracy. Additionally, none of U.S. EPA’s calculations account for the extra vulnerability of the unborn fetus and children to toxic insults."<ref>http://www.wired.com/wiredscience/2007/10/scientists-stop/</ref> EPA Assistant Administrator Jim Gulliford replied saying, "We are confident that by conducting such a rigorous analysis and developing highly restrictive provisions governing its use, there will be no risks of concern," and in October the EPA approved the use of methyl iodide as a soil ] in the U.S. It could not, however, yet be used in Washington and ] due to lack of state approval. It also was not yet approved for use in California pending approval by the California growers Department of Pesticide Regulation. The California state agency often imposes tighter restrictions than the EPA, and the previous year its top officials had expressed concerns to the EPA about methyl iodide. "We are conducting our own risk assessment of methyl iodide, and we expect that process to continue for several months before we make a decision whether or how it can be used safely in California," said Glenn Brank, a spokesman for the state Department of Pesticide Regulation.<ref>{{cite news | url = http://www.latimes.com/news/printedition/california/la-me-pesticide6oct06,0,3454295.story | title = EPA approves new pesticide despite scientists' concerns | work = ] | date = October 6, 2007}}</ref><ref>{{cite news | url = http://www.hcn.org/blogs/goat/california-sun-and-spray | title = California sun and spray | work = ] | date = August 4, 2009}}</ref>
			==Use as a pesticide==
	In February 2010, the California Department of Pesticide Regulation (DPR) concluded that methyl iodide is "highly toxic," and that "any anticipated scenario for the agricultural or structural fumigation use of this agent would result in exposures to a large number of the public and thus would have a significant adverse impact on the public health." It also concluded that adequate control of the chemical in these circumstances would be "difficult, if not impossible."<ref>{{cite news | url = http://www.cdpr.ca.gov/docs/risk/mei/peer_review_report.pdf | title = Report of the Scientific Review Committee on Methyl Iodide to the Department of Pesticide Regulation | work = special Scientific Review Committee of the California Department of Pesticide Regulation | date = February 5, 2010}}</ref>
			Iodomethane had also been proposed for use as a ], ], ], ], and as a soil disinfectant, replacing methyl bromide (also known as ]) (banned under the ]). Manufactured by ] and sold under the brand name MIDAS, iodomethane is registered as a pesticide in the U.S., Mexico, Morocco, Japan, Turkey, and New Zealand and registration is pending in Australia, Guatemala, Costa Rica, Chile, Egypt, Israel, South Africa and other countries.<ref>{{cite news|url=https://www.businesswire.com/news/home/20101025006234/en/Iodomethane-Approved-Mexico-Morocco |title=Iodomethane Approved in Mexico and Morocco |work=] |date=October 25, 2010 |access-date=2018-11-25}}</ref> The first commercial applications of iodomethane soil fumigant in California began in Fresno County in May 2011.<ref>{{cite web |author1=Nathan Rice |title=The fight over a much-needed pesticide: methyl iodide |url=https://www.hcn.org/issues/43-12/the-fight-over-a-much-needed-pesticide-methyl-iodide/ |website=] |access-date=9 June 2024 |date=25 July 2011}}</ref>
	On December 1, 2010, methyl iodide use was approved as a pesticide in the State of California.<ref>{{cite news | url = http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2010/12/01/national/a143424S98.DTL&tsp=1 | title = Calif approves use of pesticide linked to cancer | work = ] | date = December 1, 2010}}</ref> Following the approval, a coalition of environmentalists, researchers and farmers—including California State Assemblyman ], D-Carmel—gathered at locations in ] and six other sites around California to protest the impending use of methyl iodide and to ask governor-elect ] to block it. Critics of methyl iodide cite both the cancer-causing aspects of the ] and the potential for it to leach out of fields, contaminating water supplies.<ref>{{cite news | url = http://www.mercurynews.com/breaking-news/ci_16745459?nclick_check=1 | title = Statewide protest targets new strawberry pesticide | work = ] | date = November 30, 2010}}</ref> Objections were also raised by two dozen California legislators and 54 scientists, including five ].<ref name="sfgate.com"/>		Iodomethane had been approved for use as a ] by the ] in 2007 as a pre-plant ] used to control insects, plant parasitic nematodes, soil borne pathogens, and weed seeds.<ref name="sfgate.com">Zitto, Kelly {{cite news | url = http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/12/01/BAOQ1GKKKN.DTL | title = Methyl iodide gains state OK for use on crops | work = ] | date = December 2, 2010 | first=Kelly | last=Zito}}</ref> The compound was registered for use as a preplant soil treatment for field grown strawberries, peppers, tomatoes, grape vines, ornamentals and turf and nursery grown strawberries, stone fruits, tree nuts, and conifer trees. After the discovery phase in a consumer lawsuit, the manufacturer withdrew the fumigant citing its lack of market viability.<ref name=scrapped> ''San Jose Mercury News'' March 20, 2012</ref>
			The use of iodomethane as a fumigant has drawn concern. For example, 54 chemists and physicians contacted the U.S. EPA in a letter, saying "We are skeptical of U.S. EPA's conclusion that the high levels of exposure to iodomethane that are likely to result from broadcast applications are 'acceptable' risks. U.S. EPA has made many assumptions about toxicology and exposure in the risk assessment that have not been examined by independent scientific peer reviewers for adequacy or accuracy. Additionally, none of U.S. EPA's calculations account for the extra vulnerability of the unborn fetus and children to toxic insults."<ref>{{cite magazine| url=https://www.wired.com/wiredscience/2007/10/scientists-stop/ | magazine=Wired | first=Brandon | last=Keim | title=Scientists Stop EPA From Pushing Toxic Pesticide | date=October 1, 2007}}</ref> EPA Assistant Administrator Jim Gulliford replied saying, "We are confident that by conducting such a rigorous analysis and developing highly restrictive provisions governing its use, there will be no risks of concern," and in October the EPA approved the use of iodomethane as a soil ] in the United States.
	On January 5, 2011, a coalition of farmworkers, community advocates and environmental health organizations sued to challenge California's approval of methyl iodide. The plaintiff groups are: Pesticide Action Network North America, United Farm Workers of America, Californians for Pesticide Reform, Pesticide Watch Education Fund, Worksafe, Communities and Children Advocates Against Pesticide Poisoning as well as farmworkers Jose Hidalgo Ramon and Zeferino Estrada. The suit challenges the state Department of Pesticide Regulation's December 20, 2010 approval of methyl iodide for use in California on the grounds that it violates the California Environmental Quality Act, the California Birth Defects Prevention Act, and the Pesticide Contamination Prevention Act. The suit also contends that the Department of Pesticide Regulation violated the law requiring involvement of the Office of Environmental Health Hazard Assessment in the development of farmworker safety regulations and made an unlawful finding of emergency with its request for Restricted Materials status for methyl iodide.<ref>http://www.ens-newswire.com/ens/jan2011/2011-01-05-091.html</ref>
			The California Department of Pesticide Regulation (DPR) concluded that iodomethane is "highly toxic," that "any anticipated scenario for the agricultural or structural fumigation use of this agent would result in exposures to a large number of the public and thus would have a significant adverse impact on the public health", and that adequate control of the chemical in these circumstances would be "difficult, if not impossible."<ref>{{cite news | url = http://www.cdpr.ca.gov/docs/risk/mei/peer_review_report.pdf | title = Report of the Scientific Review Committee on Methyl Iodide to the Department of Pesticide Regulation | work = special Scientific Review Committee of the California Department of Pesticide Regulation | date = February 5, 2010}}</ref> Iodomethane was approved as a pesticide in California that December.<ref>{{cite news |last1=Schwartz |first1=Carly |title=Methyl Iodide Controversy: California Officials Ignored Scientists In Approving Dangerous Pesticide |url=https://www.huffingtonpost.com/2011/08/30/california-pesticides-officials-ignored-scientists_n_942757.html |access-date=2018-11-25 |work=Huffington Post |date=31 August 2011}}</ref> A lawsuit was filed on January 5, 2011, challenging California's approval of iodomethane. Subsequently, the manufacturer withdrew the fumigant and requested that California Department of Pesticide Regulation cancel its California registration, citing its lack of market viability.<ref name=scrapped />
	The first commercial applications of MIDAS soil fumigant in California began in Fresno County, in May, 2011. To date since its federal registration as a pesticide, more than 17,000 acres of soil used for growing crops have been treated in the United States without a single reported safety or health incident. Soils treated with methyl iodide are completely free of the compound before crops are planted, and to date neither the U.S. EPA nor the U.S. Food and Drug Administration (agencies that routinely conduct pesticide residue testing of fruit and produce) have found any detectable quantity of methyl iodide in the food supply from fruit and produce grown in methyl iodide-treated soils, nor have they detected any other soil fumigant product.
	== Safety ==		==Safety==
	===Toxicity and biological effects===		===Toxicity and biological effects===
			According to the ] iodomethane exhibits moderate to high acute toxicity for inhalation and ingestion.<ref>{{Cite journal|doi=10.2134/jeq2008.0124 |pmid=19202021 |title=Degradation of Methyl Iodide in Soil: Effects of Environmental Factors |journal=] |url=http://ddr.nal.usda.gov/bitstream/10113/28473/1/IND44184498.pdf |last1=Guo |first1=Mingxin |last2=Gao |first2=Suduan |pages=513&ndash;519 |year=2009 |volume=38 |issue=2 |url-status=dead |archive-url=https://web.archive.org/web/20110814102050/http://ddr.nal.usda.gov/bitstream/10113/28473/1/IND44184498.pdf |archive-date=August 14, 2011 |df=mdy }}</ref> The ] (CDC) lists inhalation, skin absorption, ingestion, and eye contact as possible exposure routes with target organs of the eyes, skin, respiratory system, and the ]. Symptoms may include eye irritation, nausea, vomiting, dizziness, ], slurred speech, and ].<ref>{{cite web|url=https://www.cdc.gov/niosh/npg/npgd0420.html|title=CDC - NIOSH Pocket Guide to Chemical Hazards - Methyl iodide|work=cdc.gov|access-date=June 25, 2016}}</ref> In high dose acute toxicity, as may occur in industrial accidents, toxicity includes metabolic disturbance, renal failure, venous and arterial thrombosis and encephalopathy with seizures and coma, with a characteristic pattern of brain injury.<ref>{{cite journal|doi=10.1136/practneurol-2013-000565|title = Methyl iodide rhombencephalopathy: clinico-radiological features of a preventable, potentially fatal industrial accident|journal = ]|url=http://pn.bmj.com/content/13/6/393.full|last1=Iniesta|first1=Ivan|last2=Radon|first2=Mark|last3=Pinder|first3=Colin|year=2013|volume=13|issue = 6|pages = 393–395|pmid = 23847234|s2cid = 36789199}}</ref>
			Iodomethane has an {{LD50}} for oral administration to rats 76&nbsp;mg/kg, and is rapidly converted in the liver to S-methyl].<ref>{{cite journal | title = Metabolism of iodomethane in the rat | author = Johnson, M. K. | journal = ] | volume = 98 | issue = 1| pages = 38–43 | year = 1966 | doi = 10.1042/bj0980038 | pmid=5938661 | pmc=1264791}}</ref>
	According to the ] methyl iodide exhibits moderate to high
	acute toxicity for inhalation and ingestion.<ref>http://ddr.nal.usda.gov/bitstream/10113/28473/1/IND44184498.pdf</ref> The ] (CDC) lists inhalation, skin absorption, ingestion, and eye contact as possible exposure routes with target organs of the eyes, skin, respiratory system, and the ]. Symptoms may include eye irritation, nausea, vomiting, dizziness, ], slurred speech, and ].<ref>http://www.cdc.gov/niosh/npg/npgd0420.html</ref>
			In its risk assessment of iodomethane, the U.S. EPA conducted an exhaustive scientific and medical literature search over the past 100 years for reported cases of human poisonings attributable to the compound.{{cn|date=May 2024}} Citing the EPA as its source, the California Department of Pesticide Regulation said: "Over the past century, only 11 incidents of iodomethane poisoning have been reported in the published literature."<ref> (Hermouet, C. ''et al.'' 1996 & Appel, G.B. ''et al.'' 1975)</ref> "An updated literature search on May 30, 2007 for iodomethane poisoning produced only one additional case report."<ref> (Schwartz MD, ''et al.'' 2005).</ref> All but one were industrial—not agricultural—accidents, and the remaining case of poisoning was an apparent suicide. Iodomethane is routinely and regularly used in industrial processes as well as in most university and college chemistry departments for study and learning related to a variety of organic chemical reactions.{{cn|date=May 2024}}
	Methyl iodide has an {{LD50}} for oral administration to rats 76&nbsp;mg/kg, and in the ] it undergoes rapid conversion to S-methyl].<ref>{{cite journal | title = Metabolism of iodomethane in the rat | author = Johnson, M. K. | journal = ] | volume = 98 | issue = 1| pages = 38–43 | year = 1966 | doi = | pmid=5938661 | pmc=1264791}}</ref>
			In 2024, a case of a person being injected with iodomethane emerged. The subject, who was the victim of attempted murder by a GP disguised as a community nurse, went on to develop ] but survived.<ref name=iodoject>{{cite news|url= https://www.bbc.com/news/articles/c4g9ve47e92o|last=Leatherdale |first=Duncan |title=Disguised GP admits attempted murder poisoning |work=] |date=7 October 2024 |access-date=7 October 2024}}</ref>
	In its risk assessment of methyl iodide, the U.S. EPA conducted an exhaustive scientific and medical literature search over the past 100 years for reported cases of human poisonings attributable to the compound. Citing the EPA as its source, the California Department of Pesticide Regulation concluded, “Over the past century, only 11 incidents of iodomethane poisoning have been reported in the published literature.” (Hermouet, C. et al 1996 & Appel, G.B. et al 1975) “An updated literature search on May 30, 2007 for iodomethane poisoning produced only one additional case report.” (Schwartz MD, et al 2005). All but one were industrial—not agricultural—accidents, and the remaining case of poisoning was an apparent suicide. Methyl iodide is routinely and regularly used in industrial processes as well as in most university and college chemistry departments for study and learning related to a variety of organic chemical reactions.
	===Carcinogenicity in mammals===		===Carcinogenicity in mammals===
			The U.S. ] (NIOSH), the U.S. ] and the U.S. ] consider iodomethane a potential occupational carcinogen.<ref>{{cite web|url=https://www.cdc.gov/niosh/84117_43.html |title=CIB 43: MONOHALOMETHANES |url-status=dead |archive-url=https://web.archive.org/web/20110629133851/http://www.cdc.gov/niosh/84117_43.html |archive-date=June 29, 2011 |df=mdy }}</ref>
			The ] concluded based on studies performed after methyl iodide was put on the ] list that: "Methyl iodide is not classifiable as to its carcinogenicity to humans (Group 3)." {{As of|2007}} the ] classifies it as "not likely to be carcinogenic to humans in the absence of altered thyroid hormone homeostasis," i.e. it is a human carcinogen but only at doses large enough to disrupt thyroid function (via excess iodide).<ref>{{cite web |url=http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2005-0252-0056 |title=Iodomethane Pesticide Fact Sheet |year=2007 }} (36 pages, inc 12 pages of refs)</ref> However this finding is disputed by the ], which states that the EPA's assessment "appears to be based solely on a single rat inhalation study in which 66% of the control group and 54-62% of the rats in the other groups died before the end of the study". They go on to state: "The EPA appears to be dismissing early peer-reviewed studies in favor of two nonpeer-reviewed studies conducted by the registrant that are flawed in design and execution."<ref>{{cite web|url=http://www.cdpr.ca.gov/docs/risk/mei/comments/panna_mei_attach1.pdf |title=Re: Comments on the Methyl Iodide Preliminary Risk Assessment |access-date=April 26, 2011 |website=cdpr.ca.gov |url-status=dead |archive-url=https://web.archive.org/web/20110726123944/http://www.cdpr.ca.gov/docs/risk/mei/comments/panna_mei_attach1.pdf |archive-date=July 26, 2011 }}</ref> Despite requests by the U.S. EPA to the ] to bring forth scientific evidence of their claims, they have not done so.{{cn|date=May 2024}}
	Methyl iodide is listed under ] as a chemical known by the state to cause cancer or reproductive toxicity based on evaluative studies performed in the 1970s.<ref>{{cite web |url=http://www.oehha.ca.gov/prop65/prop65_list/Newlist.html |title=Proposition 65: A Chemical Listed Effective April 15, 2011 As Known To The State Of California To Cause Cancer: Epoxiconazole (15 Apr 2011) }}</ref>
	It is considered a potential occupational carcinogen by the U.S. ] (NIOSH), the U.S. ] and the U.S. ].<ref>{{cite web |url=http://www.cdc.gov/niosh/84117_43.html |title=CIB 43: MONOHALOMETHANES }}</ref> The ] concluded based on studies performed after methyl iodide was Proposition 65 listed that: “Methyl iodide is not classifiable as to its carcinogenicity to humans (Group 3).” {{As of|2007}} the ] classifies it as "not likely to be carcinogenic to humans in the absence of altered thyroid hormone homeostatis," i.e. it is a human carcinogen but only at doses large enough to disrupt thyroid function (via excess iodide).<ref>{{cite web |url=http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2005-0252-0056 |title=Iodomethane Pesticide Fact Sheet |year=2007 }} (36 pages, inc 12 pages of refs)</ref> However this finding is disputed by the ] which states that the EPA’s cancer rating "appears to be based solely on a single rat inhalation study in which 66% of the control group and 54-62% of the rats in the other groups died before the end of
	the study". They go on to state: "The EPA appears to be dismissing early peer-reviewed studies in favor of two nonpeer-reviewed studies conducted by the registrant that are flawed in design and execution."<ref>http://www.cdpr.ca.gov/docs/risk/mei/comments/panna_mei_attach1.pdf</ref> Despite requests by the U.S. EPA to the ] to bring forth scientific evidence of their claims, they have not done so.
	== References ==		==See also==
			*]
	{{reflist}}
			==References==
	== Additional sources ==
			{{Reflist|30em}}
			==Additional sources==
	* {{March4th}}		* {{March4th}}
	* Sulikowski, G. A.; Sulikowski, M. M. (1999). in Coates, R.M.; Denmark, S. E. (Eds.) ''Handbook of Reagents for Organic Synthesis, Volume 1: Reagents, Auxiliaries and Catalysts for C-C Bond Formation'' New York: Wiley, pp.&nbsp;423&ndash;26.		* Sulikowski, G. A.; Sulikowski, M. M. (1999). in Coates, R.M.; Denmark, S. E. (Eds.) ''Handbook of Reagents for Organic Synthesis, Volume 1: Reagents, Auxiliaries and Catalysts for C-C Bond Formation'' New York: Wiley, pp.&nbsp;423&ndash;26.
	* {{cite journal		* {{cite journal
	| title = Mechanisms of carcinogenicity of methyl halides.		| title = Mechanisms of carcinogenicity of methyl halides.
	| author = Bolt H. M., Gansewendt B.		|author1=Bolt H. M. |author2=Gansewendt B. | journal = ]
	| journal = ]
	| volume = 23		| volume = 23
	| issue = 3		| issue = 3
Line 150:		Line 198:
	| pmid = 8260067		| pmid = 8260067
	| doi = 10.3109/10408449309105011}}		| doi = 10.3109/10408449309105011}}
	</div>
	== External links ==		==External links==
	* {{ICSC|0509|05}}		* {{ICSC|0509|05}}
	* {{PGCH|0420}}		* {{PGCH|0420}}
Line 158:		Line 205:
	* IARC Summaries & Evaluations: , ,		* IARC Summaries & Evaluations: , ,
	*		*
	*		*
	* {{cite journal|last=Jones|first=Nicola|date=September 24, 2009|title=Strawberry pesticide leaves sour taste: Methyl iodide use by Californian farmers up for review.|journal=Nature News|url=http://www.nature.com/news/2009/090924/full/news.2009.943.html|accessdate=September 25, 2009|doi=10.1038/news.2009.943}}		* {{cite journal|last=Jones|first=Nicola|date=September 24, 2009|title=Strawberry pesticide leaves sour taste: Methyl iodide use by Californian farmers up for review.|journal=Nature News|url=http://www.nature.com/news/2009/090924/full/news.2009.943.html|access-date=September 25, 2009|doi=10.1038/news.2009.943}}
			* {{PPDB|1233|Name=Iodomethane}}
	{{Halomethanes}}
			{{halomethanes}}
	]
			{{Authority control}}
			]
	]		]
	]		]
Line 169:		Line 220:
	]		]
	]		]
			]
			]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]