{{Citation style|date=October 2024}} {{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 444042332 | Reference = <ref>[https://pmep.cce.cornell.edu/profiles/extoxnet/metiram-propoxur/pendimethalin-ext.html EXTOXNET]</ref> | ImageFile = pendimethalin v2.svg | ImageSize = | PIN = 3,4-Dimethyl-2,6-dinitro-''N''-(pentan-3-yl)aniline | OtherNames = {{ubl|penoxalin|phenoxalin|pendimethaline}} |Section1={{Chembox Identifiers | CASNo_Ref = {{cascite|correct|CAS}} | CASNo = 40487-42-1 | PubChem = 38479 | KEGG_Ref = {{keggcite|correct|kegg}} | KEGG = C11019 | ChEBI_Ref = {{ebicite|changed|EBI}} | ChEBI = 83569 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = VL6L14C06U | UNNumber = 3077 2588 | SMILES = CCC(CC)Nc1c([N+](=O)[O-])cc(C)c(C)c1[N+](=O)[O-] | EINECS = 254-938-2 | ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}} | ChemSpiderID = 35265 | InChI = 1/C13H19N3O4/c1-5-10(6-2)14-12-11(15(17)18)7-8(3)9(4)13(12)16(19)20/h7,10,14H,5-6H2,1-4H3 | InChIKey = CHIFOSRWCNZCFN-UHFFFAOYAS | StdInChI_Ref = {{stdinchicite|changed|chemspider}} | StdInChI = 1S/C13H19N3O4/c1-5-10(6-2)14-12-11(15(17)18)7-8(3)9(4)13(12)16(19)20/h7,10,14H,5-6H2,1-4H3 | StdInChIKey_Ref = {{stdinchicite|changed|chemspider}} | StdInChIKey = CHIFOSRWCNZCFN-UHFFFAOYSA-N }} |Section2={{Chembox Properties | C=13 | H=19 | N=3 | O=4 | Appearance = | Density = 1.17 g/cm<sup>3</sup> | MeltingPtC = 47 to 58 | MeltingPt_notes = | BoilingPtC = 330 | Solubility = 0.275 ppm }} |Section7={{Chembox Hazards | NFPA-H = | NFPA-F = | NFPA-R = | GHSPictograms = {{GHS07}}{{GHS09}} | GHSSignalWord = Warning | HPhrases = {{H-phrases|317|410}} | PPhrases = {{P-phrases|261|272|273|280|302+352|321|333+313|363|391|501}} | FlashPt = | AutoignitionPt = }} }}
'''Pendimethalin''' is a selective herbicide of the dinitroaniline class<ref name="Powles-Yu-2010">{{cite journal | last1=Powles | first1=Stephen B. | last2=Yu | first2=Qin | title=Evolution in Action: Plants Resistant to Herbicides | journal=Annual Review of Plant Biology | publisher=Annual Reviews | volume=61 | issue=1 | date=2010-06-02 | issn=1543-5008 | doi=10.1146/annurev-arplant-042809-112119 | pages=317–347| pmid=20192743 |author-link=Stephen Powles}} p.{{nbs}}328</ref> used preëmergently and postemergently to control annual grasses and certain broadleaf weeds. It inhibits cell division and cell elongation. Pendimethalin is approved in Europe, North America, South America, Africa, Asia and Oceania for different crops including cereals (wheat, barley, rye, triticale), corn, soybeans, rice, potato, legumes, fruits, vegetables, and nuts, plus lawns and ornamental plants.{{cn|date=February 2026}}
It is also registered in Australia,<ref>{{cite web |title=Pendimethalin 440 {{!}} 4Farmers |url=https://4farmers.com.au/products/herbicides/pendimethalin-440/ |website=4farmers.com.au |access-date=21 February 2026}}</ref> Uganda<ref>{{cite web |title=Register of Agricultural Chemicals Registered |url=https://www.agriculture.go.ug/wp-content/uploads/2023/01/Chemical-Register-Dec-2022.pdf |publisher=Republic of Uganda Ministry of Agriculture Animal Industry and Fisheries |access-date=3 March 2026 |date=16 December 2022}}</ref> and India.<ref>{{cite book |last1=Paranjape |first1=Kalyani |last2=Gowariker |first2=Vasant |last3=Krishnamurthy |first3=V.N. |last4=Gowariker |first4=Sudha |publisher=CABI |date = 2015 |title=The Pesticide Encyclopedia |isbn=978-1-78064-014-3}}</ref>
==Use== Pendimethalin protects crops like wheat, corn, soybeans, potatoes, cabbage, peas, carrots, and asparagus. It controls annual grasses and certain broadleaf weeds which interfere with growth, yield and quality of crops by competing for nutrients, water and light.
Where weed infestation is particularly bad, yield loss can render wheat production uneconomical.<ref>Clarke, Wynn, Twinning, Berry, Cook, Ellis and Gladders Pesticide availability for cereals and oilseeds following revision of Directive 91/414/EEC; effects of losses and new research priorities.'' In: HGCA Research Review.'' Nr. 70, 2009.</ref> Many other crops are grown in Europe that make a fraction of total agriculture. Herbicide options are limited for these minor crops, particularly in the vegetable sector.<ref>Little J.: '' EU´s pesticide regulation must be challenged.'' In: '' FarmBusiness.'' 2009 S. 26–27.</ref> Long-term field studies call pendimethalin efficient for controlling blackgrass.<ref>Gehring, K. and S. Thyssen: ''Unkrautmanagement im Getreidebau – Herbizid-Leistungszahl – eine mehrfaktorielle Bewertung von Herbizidbehandlungen. LFL Pflanzenschutz. Institut für Pflanzenschutz der Bayerischen Landesanstalt für Landwirtschaft.'' In: '' Freising-Weihestephan, Deutschland.'' 2004.</ref><ref>Gehring, K. and S. Thyssen: ''Unkrautmanagement im Getreidebau – Herbizid-Leistungszahl – eine mehrfaktorielle Bewertung von Herbizidbehandlungen. LFL Pflanzenschutz. Institut für Pflanzenschutz der Bayerischen Landesanstalt für Landwirtschaft.'' In: '' Freising-Weihestephan, Deutschland.'' 2007.</ref><ref>Gehring, K.: '' Ackerfuchschwanz und Windhalm – die zwei bedeutendsten Ungräser im Getreidebau.'' In: '' Getreide Magazin.'' Nr. 1, 2009, S. 20-25.</ref>
The related herbicide profluralin is more effective against johnsongrass than pendimethalin.<ref>{{cite journal |last1=Jordan |first1=T. N. |last2=Baker |first2=R. S. |last3=Barrentine |first3=W. L. |title=Comparative Toxicity of Several Dinitroaniline Herbicides |journal=Weed Science |date=1978 |volume=26 |issue=1 |pages=72–75 |doi=10.1017/S0043174500032707 }}</ref>
In 2012, {{convert|6-12|e6lb|t}} of pendimethalin was used in the US.<ref>{{cite web |last1=US EPA |first1=OCSPP |title=Pesticides Industry Sales and Usage 2008 - 2012 Market Estimates |url=https://www.epa.gov/pesticides/pesticides-industry-sales-and-usage-2008-2012-market-estimates |website=United States Environmental Protection Agency |language=en |date=29 October 2015}}</ref>
==Mode of action== Pendimethalin acts pre-weed-emergence and early post-emergence. Pendimethalin is absorbed into roots and shoots, inhibits cell division and prevents growth, to prevent weeds from emerging.<ref name = "4f infosheet">{{cite web |title=4Farmers Pendimethalin 440 EC Infosheet |url=https://4farmers.com.au/wp-content/uploads/2020/11/4F-Pendimethalin-440.pdf |website=4farmers.com.au |publisher=4Farmers Australia Pty Ltd}}</ref>
The HRAC classifies by mode of action; pendimethalin is listed as Group K1, (global), AKA Group D (Australia) or Group 3 (numeric).<ref name = "4f infosheet"/>
== Possible carcinogenic effects == At least one study suggests pendimethalin exposure is associated with pancreatic cancer.<ref name=":0">{{Cite journal |last1=Andreotti |first1=Gabriella |last2=Freeman |first2=Laura E. Beane |author-link2=Laura Beane Freeman |last3=Hou |first3=Lifang |last4=Coble |first4=Joseph |last5=Rusiecki |first5=Jennifer |last6=Hoppin |first6=Jane A. |last7=Silverman |first7=Debra T. |last8=Alavanja |first8=Michael C. R. |date=2009-05-15 |title=Agricultural pesticide use and pancreatic cancer risk in the Agricultural Health Study Cohort |journal=International Journal of Cancer |volume=124 |issue=10 |pages=2495–2500 |doi=10.1002/ijc.24185 |issn=1097-0215 |pmc=2674312 |pmid=19142867}}</ref>
A French study found no association with lung cancer.<ref>{{cite journal |last1=Boulanger |first1=Mathilde |last2=Tual |first2=Séverine |last3=Lemarchand |first3=Clémentine |last4=Baldi |first4=Isabelle |last5=Clin |first5=Bénédicte |last6=Lebailly |first6=Pierre |journal=Occupational & Environmental Medicine |title=0441 Exposure to dinitroanilines and risk of lung cancer (Lc) by subtypes: Results from the agrican cohort |date=August 2017 |volume=74 |issue=Suppl 1|page=A140.1 |doi=10.1136/oemed-2017-104636.365}}</ref>
The mechanism behind this purported increased risk is unknown, but pendimethalin exposure appears to reduce apoptosis in cultured tumor cells.<ref>{{cite journal |last1=Sarıgöl Kılıç |first1=Zehra |last2=Ündeğer Bucurgat |first2=Ülkü |title=The Apoptotic and Anti-Apoptotic Effects of Pendimethalin and Trifluralin on A549 Cells In Vitro |journal=The Turkish Journal of Pharmaceutical Sciences |date=2018 |volume=15 |issue=3 |pages=364–369 |doi=10.4274/tjps.94695|pmid=32454683 |pmc=7227839 }}</ref>
== Resistance == Herbicide resistance harms efficacy. Until 2009 pendimethalin showed no resistance. It is not cross-resistant with other grass weed herbicides, so pendimethalin can be coäpplied with herbicides of other modes of action.<ref>Moss, S. R. and R. Hull: '' The value of pre-emergence herbicides for combating herbicide-resistant Alopecurus myosuroides (blackgrass).'' In: '' Aspects of Applied Biology.'' Nr. 91, 2009.</ref> ''Lolium rigidum'' has evolved resistance to pendimethalin, at least in part due to increased cytochrome P450 activity.<ref name="Powles-Yu-2010" /> This resistance mechanism in ryegrass (shared with other dinitroanilines like trifluralin, see for longer explanation) is by an opposing mutation to resistance to prosulfocarb, a thiocarbamate herbicide. By evolving resistance to one, the weed devolves its resistance to the other.<ref>{{cite journal |last1=Chen |first1=Jinyi |last2=Yu |first2=Qin |last3=Patterson |first3=Eric |last4=Sayer |first4=Chad |last5=Powles |first5=Stephen |title=Dinitroaniline Herbicide Resistance and Mechanisms in Weeds |journal=Frontiers in Plant Science |language=English |doi=10.3389/fpls.2021.634018 |date=25 March 2021|volume=12 |article-number=634018 |doi-access=free |pmid=33841462 |pmc=8027333 }}</ref>
==Registrative status== Pendimethalin is registered globally for a wide range of crops, by the European Commission, US-EPA, Canada-PMRA, Japan, Brazil-ANVISA and others.
== Toxicology == Pendimethalin is not toxic to mammals, though interestingly the oral LD<sub>50</sub> for rats and mice is 1050-1620 mg/kg, yet for dogs and rabbits it is much less harmful, at over 5000 mg/kg. For comparison, table salt's LD<sub>50</sub> is 3000 mg/kg. There may be chronic effects however; repeated or prolonged skin exposure may cause allergic reactions such as eczema, hives or anaphylaxis. Prolonged exposure by other routes may affect changes to the liver.<ref name="4f sds">{{cite web |title=4Farmers Pendimethalin 440 Safety Sheet |url=https://4farmers.com.au/wp-content/uploads/2020/11/4FARMERS-PENDIMETHALIN-440-HERBICIDE.pdf |website=4farmers.com.au |publisher=4Farmers Australia}}</ref>
==Soil behavior== Pendimethalin is highly persistent in soil and water. It has high potential for bioaccumulation, and it is moderately mobile in soil,<ref name="4f label">{{cite web |title=4Farmers Pendimethalin 440 EC Leaflet |url=https://4farmers.com.au/wp-content/uploads/2020/11/4FARMERS-PENDIMETHALIN-440-HERBICIDE.pdf |website=4farmers.com.au |publisher=4Farmers Australia Pty Ltd}}</ref> despite it adsorbing strongly into soil.<ref>{{cite web |title=PRE-EMERGENT HERBICIDES FACT SHEET |url=https://grdc.com.au/__data/assets/pdf_file/0032/575069/GRDC_PreEmergentFS_2022_Final-approved-version.pdf |publisher=Grains Research and Development Corporation |date=2022}}</ref>
==Tradenames== Tradenames include Pendimethalin 440, Satellite, Halts, Prowl, PRE-M, Stomp, Stealth and Pendulum, Hilpendi etc.
==References== {{Reflist}}
==External links == * {{PPDB|511}}
{{Herbicides}} {{Aniline Herbicides}}
Category:Anilines Category:Nitrobenzene derivatives Category:Endocrine disruptors Category:Preemergent herbicides Category:Alkyl-substituted benzenes Category:Secondary amines Category:Group 3 herbicides Category:Dinitroaniline herbicides