SS-AGR-105 Common Name, Chemical Name and Toxicity Rating of Some Herbicides 1 J. A. Tredaway 2 Herbicides labels are required by law to contain toxicological information. These provide the necessary requirements, such as personal protective equipment (PPE), and re-entry periods into treated areas. Toxicity is defined as a measure of the amount of a compound that is harmful or lethal. Toxicity ratings determine if the pesticide is classified as a restricted use product, thereby requiring a pesticide application license. The information given in Table 1 and Table 2 provides toxicity ratings of the active ingredient of various herbicides. Be sure to read the complete pesticide label for instructions on the safe use of the product being applied. The toxicity ratings given below refer to the acute oral toxicity as measured by the LD 50. Evaluations are conducted on test animals, which are normally rats, over a prescribed length of time. The acute oral toxicity is the single dose in mg/kg (mg of compound per kg body weight) taken by mouth or ingested that will kill 50% of the animal test population. It is assumed that the same dosage would apply to humans and is therefore adopted as the standard. There are other toxicity determinations that are made including skin or dermal toxicity, eye irritations, inhalation hazard, and fish or bird (avian) toxicity. The results of these tests also determine warnings or restrictions that are placed on pesticide labels. 1. This document is SS-AGR-105, one of a series of the Agronomy Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Revised January 2000. Please visit the EDIS Web site at http://edis.ifas.ufl.edu. 2. J. A. Tredaway, assistant professor, Agronomy Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, 32611. The use of trade names in this publication is solely for the purpose of providing specific information. It is not a guarantee or warranty of the products named and does not signify that they are approved to the exclusion of others of suitable composition. 3.3.1 The Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information and other services only to individuals and institutions that function without regard to race, color, sex, age, handicap, or national origin. For information on obtaining other extension publications, contact your county Cooperative Extension Service office. Florida Cooperative Extension Service/Institute of Food and Agricultural Sciences/University of Florida/Christine Taylor Waddill, Dean.
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 2 Table 1. Explanation of toxicity ratings used in Table 2. Toxicity rating Signal Word Class Oral LD50 (MG/KG) Probable lethal dose for 150 lb. Man I DANGER, POISON Very High less than 50 a taste to 1 teaspoon II WARNING High 50 to 500 1 teaspoon to 1 tablespoon III CAUTION Moderate 501 to 5000 1 ounce to 1 pint IV CAUTION Low greater than 5000 1 pint to 1 quart or more
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 3 Common name Toxicity rating Chemical name acifluorfen III 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid ametryn III N-ethyl-N-(1-methylethyl)-6-methylthio)-1,3,5-triazine-2,4-diamine amitrole IV 1H-1,2,4-triazol-3-amine asulam III methyl[(4-aminophenyl)sulfanyl]carbamate atrazine III 6-chloro-N-ethyl-N benefin IV N-butyl-N-ethyl-2,6-dinitro-4-(trifluoro methyl)benzenamine bensulide III 0,0-bis(1-methylethyl) S-[2-[(phenylsulfonyl)amino]ethyl]phosphorodithiote bentazon III 3-isopropyl-1H-2,1,3-benzothiadiazin-(4) 3H-one 2,2-dioxide bromacil IV 5-bromo-6-methyl-3-(1 methylpropyl)-2,4(1h,3h) pyrimidinedione bromoxynil III 3,5-dibromo-4-hydroxybenzonitrile butylate III s-ethyl bis(2-methylpropyl)carbamothioate cacodylic acid III dimethyl arsinic acid carfentrazone IV,2-dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo1H -1,2,4-triazole-1-yl)-4-fluorobenzenepropanoic acid, ethyl ester chlorimuron III ethyl 2-[[[[(4-chloro-6-methoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]benzoate cloransulam IV 3-chloro-2-[[(5-ethoxy-7-fluoro[1,2,4]triazolo[1,5- c]pyrimidin-2yl)sulfonyl]amino]benzoic acid, methyl ester clethodim III (E,E)-( clomozone III 2-[(2-chlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone clopyralid III 3,6-dichloro-2-pyridinecarboxylic acid cyanazine II 2-[[4-chloro-6-(ethylamino)-s-triazin-2 yl]amino]-2-methylpropionitrile cycloate III S-ethyl cyclohexylethylcarbamothioate DCPA IV dimethyl 2,3,5,6-tetrachloro-1,4-benzene di carboxylate
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 4 dicamba III 3,6-dichloro-0-anisic acid dichlobenil III 2,6-dichlorobenzonitrile dichlorprop III (acid dichlormid III 2,2-dichloro-N-N-di-2-propenylacetamide diclofop III (acid diclosulam IV N -(2,6)-dichlorophenyl)-5-ethoxy-7-fluro(1,2,4)triazolo-(1,5c)-pyrimidine-2-sulfonamide diquat I 6-7-dihydrodipyrido[1,2-a:2',1'-c]pyrazinediium ion dithiopyr IV S-S-dimethyl 2-(difluoromethyl)-4-(2-methylpropyl)-6(trifluoromethyl)-3,5-pyridinedicarbothioate diuron III 3-(3,4-dichlorophenyl)-1,1-dimethylurea DSMA III disodium methanearsonate endothall I 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethalfluralin IV N-ethyl-N-(2-methyl-2-propenyl)-2,6-dinitro-4-(trifluoromethyl)benzeamine ethofumesate IV (methanesulfonate EPTC III S-ethyl dipropylthiocarbamate fenoxaprop III (acid flumetsulam IV N-(2,6-difluorophenyl)-5-methyl[1,2,4]triazolo[1,5-a]pyrimidine-2-sulfonamide flumioxazin IV 2-[7-fluoro-3,4-dihydro-3-oxo-4-(2-propynyl)-2H -1,4-benzoxazin-6-yl]-4,5,6,7-tetrahydro-1H-isoindole-1,3(2H)-dione fluometuron IV N,N-dimethyl-N-[3-trifluoromethyl)phenyl]urea fluzaifop-p III (R)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenoxy]propanoic acid glufosinate III 2-amino-4-(hydroxymethylphosphinyl)butanoic acid glyphosate IV N-(phosphonomethyl-glycine
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 5 halosulfuron III methyl 6[((4,6-dimethoxy-2-pyrimidinyl)-amino)carbonylaminosulfonyl]-4-chloro-1-methyl-1Hpyrazole-4-carboxylate hexazinone III 3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione imazapyr IV (H-imidazol-2-yl]-3-pyridinecarboxylic acid imazapyr IV (H-imidazol-2-yl]-3-pyridinecarboxylic acid imazaquin IV 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H -imidazol-2-yl]-3-quinolinecarboxylic acid imazethapyr IV (ethyl)-5-oxo-1h-imidazol-2-yl]-5-ethyl-3-pyridinecarbolic acid isoxaben IV N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide lactofen IV (5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate linuron III 3-(3,4-dichlorophenyl)-1-methoxyl-1-methylurea mecoprop III 2[(4-chloro-o-tolyl)oxy]propionic acid metolachlor III 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide metribuzin III 4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazine-5(4H)one metsulfuron IV methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino[sulfonyl]benzoate molinate III S-ethyl hexahydro-1h-azepine-1-carbothioate MSMA III monosodium methanearsonate napropamide IV N,N-diethyl-2-(1-naphthalenyloxy)propanamide naptalam III 2-[(1-naphthalenylamino)carbonyl]benzoic acid nicosulfuron IV 2-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]- N,N-dimethyl-3-pyridinecarboxamide norflurazon III 4-chloro-5-(methylamino)-2-(3-trifluoromethyl)phenyl)-3(2H)-pyridazinone oryzalin III 4-dipropylamino)-3,5-dinitrobenzenesulfonamide
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 6 oxadiazon III 3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethyl)-1,3,4-oxadiazol-2-(3H )-one oxyfluorfen III 2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-trifluoromethyl)benzene paraquat I 1,1'-dimethyl-4,4'-bipyridinium ion pebulate III S-propyl butylethylcarbamothioate pendimethalin III N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine prometon III 6-methoxy-N,N-bis(1-methylethyl)-1,3,5-triazine-2,4-diamine prometryn IV N,N-bis(1-methylethyl)-6-(methylthio)-1,3-5-triazine-2,4-diamine pronamide IV 3,5-dichloro(N-1,1-dimethyl-2-propyny)benzamide propachlor III 2-chloro-N-isopropylacetanilide propanil III N-3,4-dichloropropionanilide pyridate III O-(6-chloro-3-phenyl-4-pyridazinyl)-S-octyl-carbohothioate quizalofop-p III (R)-2-[4-(6-chloro-2-quinoxalinyl)oxy)phenoxy]propanoic acid rimsulfuron IV N -[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(ethylsulfonyl)-2- pyridinesulfonamide sethoxydim III 2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one simazine III 6-chloro-N,N-diethyl-1,3,5-triazine-2,4-diamine sulfosate IV sulfonium, trimethyl-salt with N-(phosphonomethyl)glycine (1:1) tebuthiuron III N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N terbacil III S-chloro-3-(1,1-dimethylethyl)-6-methyl-2,4-(1H,3H)-pyrimidinedione triclopyr III [(3,5,6-trichloro-2-pyridinyl)xoy]acetic acid trifluralin IV 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine vernolate III S-propyl dipropylcarbamothioate
Common Name, Chemical Name and Toxicity Rating of Some Herbicides 7 2,4-D III (2,4-dichlorophenoxy)acetic acid 2,4-DB III 4-(2,4-dichlorophenoxy)butyric acid