Chloropicrin: Difference between revisions

|Watchedfields = changed

|verifiedrevid = 444854343

|ImageFileL1 =chloropicrin.png

|ImageFileR1 = Chloropicrin-3D-balls.png

|IUPACName = Trichloro(nitro)methane

|OtherNames = {{ubl|Nitrochloroform|Nitrotrichloromethane|PS|Tri-clor|Trichloronitromethane}}

|Section1={{Chembox Identifiers

|IUPHAR_ligand = 6292

|InChI = 1/CCl3NO2/c2-1(3,4)5(6)7

|InChIKey = LFHISGNCFUNFFM-UHFFFAOYAJ

|StdInChI_Ref = {{stdinchicite|correct|chemspider}}

|StdInChI = 1S/CCl3NO2/c2-1(3,4)5(6)7

|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|StdInChIKey = LFHISGNCFUNFFM-UHFFFAOYSA-N

|CASNo = 76-06-2

|CASNo_Ref = {{cascite|correct|CAS}}

|PubChem = 6423

|UNII_Ref = {{fdacite|correct|FDA}}

|UNII = I4JTX7Z7U2

|ChEBI_Ref = {{ebicite|correct|EBI}}

|ChEBI = 39285

|ChEMBL = 1327143

|Beilstein = 1756135

|Gmelin = 240197

|EC_number = 200-930-9

|RTECS = PB6300000

|UNNumber = 1580

|SMILES = ClC(Cl)(Cl)[N+]([O-])=O

|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

|ChemSpiderID = 13861343

|KEGG_Ref = {{keggcite|correct|kegg}}

|KEGG = C18445

}}

|Section2={{Chembox Properties

|Formula = {{chem2|CCl3NO2}}

|MolarMass = 164.375 g/mol

|Appearance = colorless liquid

|Odor = irritating<ref name=PGCH/>

|Density = 1.692&nbsp;g/ml<ref>http://msds.chem.ox.ac.uk/CH/chloropicrin.html {{Dead link|date=August 2022}}</ref>

|MeltingPtC = -69

|BoilingPtC = 112

|BoilingPt_notes = (decomposes)

|Solubility = 0.2%<ref name=PGCH/>

|VaporPressure = 18 mmHg (20°C)<ref name=PGCH/>

|MagSus = −75.3·10⁻⁶ cm³/mol

}}

|Section7={{Chembox Hazards

|MainHazards = Extremely toxic and irritating to skin, eyes, and lungs. Carcinogenic.

|GHSPictograms = {{GHS05}}{{GHS06}}{{GHS08}}{{GHS09}}

|GHSSignalWord = Danger

|HPhrases = {{H-phrases|301|314|330|370|372|410}}

|PPhrases = {{P-phrases|260|264|270|271|273|280|284|301+310|301+330+331|303+361+353|304+340|305+351+338|307+311|310|314|320|321|330|363|391|403+233|405|501}}

|NFPA-H = 4

|NFPA-F = 0

|NFPA-R = 3

|PEL = TWA 0.1 ppm (0.7 mg/m³)<ref name=PGCH>{{PGCH|0132}}</ref>

|REL = TWA 0.1 ppm (0.7 mg/m³)<ref name=PGCH/>

|IDLH = 2 ppm<ref name=PGCH/>

|LC50 = 9.7 ppm (mouse, 4 hr)<br />117 ppm (rat, 20 min)<br />14.4 ppm (rat, 4 hr)<ref name=IDLH>{{IDLH|76062|Chloropicrin}}</ref>

|LCLo = 293 ppm (human, 10 min)<br />340 ppm (mouse, 1 min)<br />117 ppm (cat, 20 min)<ref name=IDLH/>

}}

'''Chloropicrin''', also known as '''PS''' (from [[Port Sunlight]]<ref>{{cite book|last1=Foulkes|first1=C.H.|title="GAS!" — The Story of the Special Brigade|date=31 Jan 2012|publisher=Andrews UK Limited|page=193}}</ref>) and '''nitrochloroform''', is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, [[herbicide]], [[insecticide]], and [[nematicide]].<ref name="RED Fact Sheet">{{cite web|title=RED Fact Sheet: Chloropicrin|url=http://www.epa.gov/oppsrrd1/REDs/factsheets/chloropicrin-fs.pdf|publisher=US Environmental Protection Agency|access-date=20 September 2013|page=2|date=10 July 2008}}</ref> It was used as a [[poison gas in World War I]] and the [[Russian invasion of Ukraine|Russian Invasion of Ukraine.]]<ref>{{Cite web |last=Office of the Spokesperson |date=1 May 2024 |title=Imposing New Measures on Russia for its Full-Scale War and Use of Chemical Weapons Against Ukraine |url=https://www.state.gov/imposing-new-measures-on-russia-for-its-full-scale-war-and-use-of-chemical-weapons-against-ukraine-2/#:~:text=The%20Department%20of%20State%20has,Chemical%20Weapons%20Convention%20(CWC). |url-status=live |archive-url=https://web.archive.org/web/20240523134544/https://www.state.gov/imposing-new-measures-on-russia-for-its-full-scale-war-and-use-of-chemical-weapons-against-ukraine-2/ |archive-date=23 May 2024 |access-date=23 May 2024 |website=U.S. Department of State}}</ref> Its chemical structural formula is {{chem2|Cl3C\sNO2|auto=1}}.

==Synthesis==

Chloropicrin was discovered in 1848 by Scottish chemist [[John Stenhouse]]. He prepared it by the reaction of [[sodium hypochlorite]] with [[picric acid]]:<!--eq is an approx guess-->

:{{chem2|HOC6H2(NO2)3 + 11 NaOCl → 3 Cl3CNO2 + 3 [[sodium carbonate|Na2CO3]] + 3 [[sodium hydroxide|NaOH]] + 2 [[sodium chloride|NaCl]]}}

Because of the precursor used, Stenhouse named the compound chloropicrin, although the two compounds are structurally dissimilar.

Today, chloropicrin is manufactured by the reaction of [[nitromethane]] with [[sodium hypochlorite]]:<ref>Sheldon B. Markofsky "Nitro Compounds, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005.</ref>

:{{chem2|H3CNO2 + 3 NaOCl → Cl3CNO2 + 3 NaOH}}

Reaction of [[chloroform]] and [[nitric acid]] also yields chloropicrin:<ref>''Chloropicrin'' Kirby E. Jackson, Chemical Reviews 1934 14 (2), 251-286

[https://doi.org/10.1021/cr60048a003 DOI: 10.1021/cr60048a003]</ref>

:{{Chem2|Cl3CH + HONO2 -> Cl3CNO2 + H2O}}

Chloropicrin's chemical formula is {{chem2|CCl3NO2}} and its molecular weight is 164.38 grams/mole.<ref name=DPR_ExecSum>{{cite web|title=Executive Summary - Evaluation of Chloropicrin As A Toxic Air Contaminant|url=http://www.cdpr.ca.gov/docs/emon/pubs/tac/exec_sum_0210.pdf|publisher=Department of Pesticide Regulation - California Environmental Protection Agency|access-date=20 September 2013|page=iv|date=February 2010|archive-url=https://web.archive.org/web/20131006220801/http://www.cdpr.ca.gov/docs/emon/pubs/tac/exec_sum_0210.pdf|archive-date=6 October 2013|url-status=dead}}</ref> Pure chloropicrin is a colorless liquid, with a boiling point of 112&nbsp;°C.<ref name="DPR_ExecSum"/> Chloropicrin is sparingly soluble in water with solubility of 2&nbsp;g/L at 25&nbsp;°C.<ref name="DPR_ExecSum"/> It is volatile, with a vapor pressure of 23.2 [[millimeters of mercury]] (mmHg) at 25&nbsp;°C; the corresponding [[Henry's law]] constant is 0.00251&nbsp;atmosphere-cubic meter per mole.<ref name="DPR_ExecSum"/> The [[octanol-water partition coefficient]] (''K''_ow) of chloropicrin is estimated to be 269.<ref name="DPR_ExecSum"/> Its soil adsorption coefficient (''K''_oc; normalized to soil organic matter content) is 25&nbsp;cm³/g.<ref name="DPR_ExecSum"/>

==Use==

Chloropicrin was manufactured for use as [[poison gas in World War I]].<ref>{{cite book |last=Ayres |first=Leonard P. |title =The War with Germany |url=https://archive.org/details/warwithgermanya02ayregoog |publisher =United States Government Printing Office |edition =Second |date =1919 |location =Washington, DC |page =[https://archive.org/details/warwithgermanya02ayregoog/page/n86 80]}}</ref> In agriculture, chloropicrin is injected into soil prior to planting a crop to [[fumigation|fumigate]] soil. Chloropicrin affects a broad spectrum of [[fungi]], [[microbes]] and [[insects]].<ref name=chloro_background>{{cite web|title=Chloropicrin – Background|url=http://www.chloropicrinfacts.org/background.html|access-date=20 September 2013}}</ref><ref name="fumigant">{{cite web |url=http://www.workcover.nsw.gov.au/Documents/Publications/AlertsGuidesHazards/DangerousGoodsExplosivesFireworksPyrotechnics/chloropicrin_fact_sheet_1371.pdf |title=Factsheet: Chloropicrin |website=www.workcover.nsw.gov.au |archive-url=https://web.archive.org/web/20090520095913/http://www.workcover.nsw.gov.au/Documents/Publications/AlertsGuidesHazards/DangerousGoodsExplosivesFireworksPyrotechnics/chloropicrin_fact_sheet_1371.pdf |archive-date=May 20, 2009}}</ref> It is commonly used as a stand-alone treatment or in combination / co-formulation with [[methyl bromide]] and [[1,3-dichloropropene]].<ref name="fumigant" /><ref name="google">{{cite book| author = Amos Alfred Fries|author2=Clarence Jay West| title = Chemical warfare| url = https://archive.org/details/chemicalwarfare00westgoog| year = 1921| publisher = McGraw-Hill book company, inc.| page = [https://archive.org/details/chemicalwarfare00westgoog/page/n160 144]}}</ref>

Chloropicrin is used as an indicator and repellent when fumigating residences for insects with [[sulfuryl fluoride]] which is an odorless gas.<ref>{{cite web |url=http://termitetenting.com/ |title = Vikane® gas fumigant – Trusted by Homeowners, Preferred by Professionals}}</ref> Chloropicrin's [[mode of action]] is unknown<ref name="PPDB" /> (IRAC MoA 8B).<ref name="IRAC-MoAs-9.4" /> Chloropicrin may stimulate [[weed]] [[germination]], which can be useful when quickly followed by a more effective [[herbicide]].<ref name="Martin-2003">{{cite journal | last=Martin | first=Frank N. | title=Development of Alternative Strategies for Management of Soilborne Pathogens Currently Controlled with Methyl Bromide | journal=[[Annual Review of Phytopathology]] | publisher=[[Annual Reviews (publisher)|Annual Reviews]] | volume=41 | issue=1 | year=2003 | issn=0066-4286 | doi=10.1146/annurev.phyto.41.052002.095514 | pages=325–350| pmid=14527332}}</ref>

In February 2024, [[Ukraine|Ukrainian]] General [[Oleksandr Tarnavskyi]] accused the [[Russian Armed Forces]] of using chloropicrin [[munitions]].<ref>{{cite web |title=Ukraine accuses Russia of intensifying chemical attacks on the battlefield |url=https://www.reuters.com/world/europe/ukraine-accuses-russia-intensifying-chemical-attacks-battlefield-2024-02-09/ |website=Reuters |access-date=2024-02-10}}</ref> In May 2024, the [[United States Department of State]] also alleged use of chloropicrin by Russian forces in Ukraine, and imposed sanctions against Russian individuals and entities as a response.<ref>{{cite web |title=Imposing New Measures on Russia for its Full-Scale War and Use of Chemical Weapons Against Ukraine |url=https://www.state.gov/imposing-new-measures-on-russia-for-its-full-scale-war-and-use-of-chemical-weapons-against-ukraine-2/ |publisher=United States Department of State |access-date=2 May 2024}}</ref>

At a national level, chloropicrin is regulated in the [[United States]] by the [[United States Environmental Protection Agency]] as a restricted use [[pesticide]].<ref name="chloro_background"/><ref name=DPR_MitPro1>{{cite web|title=Chloropicrin Mitigation Proposal|url=http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|publisher=Department of Pesticide Regulation – California Environmental Protection Agency|access-date=20 September 2013|page=1|date=15 May 2013|archive-url=https://web.archive.org/web/20131006220459/http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|archive-date=6 October 2013|url-status=dead}}</ref> Because of its toxicity and [[carcinogen]]icity, distribution and use of chloropicrin is available only to licensed professionals and specially certified growers who are trained in its proper and safe use.<ref name="chloro_background"/><ref name="DPR_MitPro1"/> In the US, occupational exposure limits have been set at 0.1 ppm over an eight-hour time-weighted average.<ref name=cdc>{{cite web|title = NIOSH Pocket Guide to Chemical Hazards|url=https://www.cdc.gov/niosh/npg/npgd0132.html|publisher=Centers for Disease Control and Prevention|access-date=7 November 2013}}</ref>

===Agriculture===

In 2008 the US [[United States Environmental Protection Agency|EPA]] re-approved chloropicrin as safe for use in agricultural settings, stating that treatments "can provide benefits to both food consumers and growers. For consumers, it means more fresh fruits and vegetables can be cheaply produced domestically year-round because several severe pest problems can be efficiently controlled."<ref>{{cite web|title=Amended Reregistration Eligibility Decision (RED) for Chloropicrin|url=http://www.epa.gov/oppsrrd1/REDs/chloropicrin-red-amended.pdf|publisher=United States Environmental Protection Agency|access-date=20 September 2013|date=May 2009}}</ref>{{dead link|date=May 2024}}<ref name=DPR_MitPro2>{{cite web|title=Chloropicrin Mitigation Proposal|url=http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|publisher=Department of Pesticide Regulation – California Environmental Protection Agency|access-date=20 September 2013|page=2|date=15 May 2013|archive-url=https://web.archive.org/web/20131006220459/http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|archive-date=6 October 2013|url-status=dead}}</ref><ref name=safety>{{cite web|title=Environmental Protection Agency (EPA) Re-Registers Chloropicrin As Safe For Use Nationwide|url=http://www.chloropicrinfacts.org/safety.html|access-date=22 October 2013}}</ref> To ensure chloropicrin is used safely, the EPA requires a strict set of protections for handlers, workers, and persons living and working in and around farmland during treatments.<ref name="chloro_background"/><ref name="DPR_MitPro2"/> EPA protections were increased in both 2011 and 2012, reducing [[fumigant]] exposures and significantly improving safety.<ref name=DPR_MitProQuote>{{cite web|title=Chloropicrin Mitigation Proposal|url=http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|publisher=Department of Pesticide Regulation – California Environmental Protection Agency|access-date=20 September 2013|page=2|date=15 May 2013|quote=The Amended RED incorporated final new safety measures to increase protections for agricultural workers and bystanders. These measures establish a baseline for safe use of the soil fumigants throughout the United States, reducing fumigant exposures and significantly improving safety.|archive-url=https://web.archive.org/web/20131006220459/http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|archive-date=6 October 2013|url-status=dead}}</ref> Protections include the training of certified applicators supervising pesticide application, the use of buffer zones, posting before and during pesticide application, fumigant management plans, and compliance assistance and assurance measures.<ref name="safety"/><ref name=faq>{{cite web|title=Chloropicrin – Frequently Asked Questions|url=http://www.chloropicrinfacts.org/faq.html|access-date=21 October 2013}}</ref>

Used as a preplant soil treatment measure, chloropicrin suppresses soilborne pathogenic [[fungi]] and some [[nematodes]] and [[insects]]. According to chloropicrin manufacturers, with a [[half-life]] of hours to days, it is completely digested by soil organisms before the crop is planted, making it safe and efficient.{{rs?|date=May 2024}} Contrary to popular belief, chloropicrin does not [[Sterilization (microbiology)|sterilize]] soil and does not [[Ozone depletion|deplete the ozone layer]], as the compound is destroyed by sunlight. Additionally, chloropicrin has never been found in [[groundwater]], due to its low solubility.<ref>{{cite web |url= https://www.plantmanagementnetwork.org/edcenter/seminars/potato/Chloropicrin/ |title=Chloropicrin Soil Fumigation in Potato Production Systems|work=Plant Management Network |publisher=American Phytopathological Society |access-date= 1 Apr 2019}}</ref>

====California====

In [[California]], experience with acute effects of chloropicrin when used as a soil fumigant for [[strawberries]] and other [[crops]] led to the release of regulations in January 2015 creating buffer zones and other precautions to minimize exposure of farm workers, neighbors, and passersby.<ref name=CDPR01615>{{cite web|title=Control Measures for Chloropicrin|url=http://www.cdpr.ca.gov/docs/whs/pdf/control_measures_chloropicrin_summary.pdf|publisher=California Department of Pesticide Regulation|access-date=January 15, 2015|date=January 6, 2015|quote=added controls for chloropicrin when it is used as a soil fumigant. The controls are intended to reduce risk from acute (short-term) exposures that might occur near fields fumigated with products containing chloropicrin.|archive-url=https://web.archive.org/web/20150128143316/http://www.cdpr.ca.gov/docs/whs/pdf/control_measures_chloropicrin_summary.pdf|archive-date=January 28, 2015|url-status=dead}}</ref><ref name=DPR_MitProQuote2>{{cite web|title=Chloropicrin Mitigation Proposal|url=http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|publisher=Department of Pesticide Regulation – California Environmental Protection Agency|access-date=20 September 2013|page=2|date=15 May 2013|quote=The new measures appearing on soil fumigant Phase 2 labels include buffer zones and posting, emergency preparedness and response measures, training for certified applicators supervising applications, Fumigant Management Plans, and notice to State Lead Agencies who wish to be informed of applications in their states.|archive-url=https://web.archive.org/web/20131006220459/http://www.cdpr.ca.gov/docs/whs/pdf/dpr_chloropicrin_mitigation_proposal_and_app_1-3.pdf|archive-date=6 October 2013|url-status=dead}}</ref>

===High concentrations===

[[File:"Chlorpicrin, it smelled like flypaper" (OHA 365), National Museum of Health and Medicine (5405373108).jpg|thumb|348x348px|Gas identification art for chloropicrin]]

Chloropicrin is harmful to humans. It can be absorbed systemically through inhalation, ingestion, and the skin. At high concentrations, it is severely irritating to the lungs, eyes, and skin.<ref>[https://www.cdc.gov/niosh/ershdb/EmergencyResponseCard_29750034.html Chloropicrin (PS): Lung Damaging Agent]. National Institute for Occupational Safety and Health. Emergency Response Safety and Health Database, August 22, 2008. Retrieved December 23, 2008.</ref> In [[World War I]], German forces used concentrated chloropicrin against Allied forces as a [[lachrymatory agent|tear gas]]. While not as lethal as other chemical weapons, it induced [[vomiting]] and forced Allied soldiers to remove their masks to vomit, exposing them to more toxic gases used as weapons during the war.<ref>{{Cite journal |last=Heller |first=Charles E. |date=September 1984 |title=Chemical Warfare in World War I: The American Experience, 1917-1918 |url=https://www.armyupress.army.mil/Portals/7/combat-studies-institute/csi-books/leavenworth-papers-10-chemical-warfare-in-world-war-i-the-american-experience-1917-1918.pdf |journal=Leavenworth Papers |issue=10 |pages=23}}</ref>

==Damage to protective gear==

Chloropicrin and its derivative [[phosgene oxime]] have been known to damage or compromise earlier generations of personal protective equipment. Some of the soldiers attacked mentioned a white smoke emerging from their gas masks.{{citation needed|date=July 2022}}

==See also==

*[[Trichloronitrosomethane]]

*[[Tetrachlorodinitroethane]]

{{reflist|refs=

<ref name="IRAC-MoAs-9.4">{{cite web|url=http://irac-online.org/documents/moa-classification/|title=IRAC Mode of Action Classification Scheme Version 9.4|website=IRAC ([[Insecticide Resistance Action Committee]])|type=pdf|date=March 2020}}</ref>

<ref name="PPDB">{{PPDB|148}}, [[University of Hertfordshire]], accessed 2021-03-10.</ref>

}}

[[Category:Nitro compounds]]

[[Category:Trichloromethyl compounds]]

[[Category:Fungicides]]

[[Category:Herbicides]]

[[Category:Insecticides]]

[[Category:Nematicides]]