WO2001005225A1

WO2001005225A1 - Aqueous concentrate pesticidal compositions having improved dermal and ocular safety

Info

Publication number: WO2001005225A1
Application number: PCT/US2000/019317
Authority: WO
Inventors: Daniel R. Wright
Original assignee: Monsanto Technology Llc
Priority date: 1999-07-19
Filing date: 2000-07-17
Publication date: 2001-01-25
Also published as: HUP0202309A3; ZA200110533B; EP1199928A1; CA2375949A1; EA200200180A1; AU6215900A; CN1361662A; BR0012549A; CZ2002174A3; MXPA02000622A; HUP0202309A2; AR024801A1; JP5529361B2; JP2003504381A

Abstract

An aqueous concentrate pesticidal composition is provided, comprising (a) a water-soluble pesticide in an amount of about 50 to about 500 g/l; (b) an etheramine surfactant; and (c) an anionic surfactant having the chemical formula (III) R?7-(O-R8)¿n-O-X where R7 is a C¿4-22? linear or branched, saturated or unsaturated, aliphatic hydrocarbyl or a (C8-12 alkyl)phenyl group, R?8¿ groups are independently C¿2-4? alkylidene groups, n is 0 to about 60 and X is an anionic radical selected from carboxylate, ether carboxylate, sulfate and phosphate; the weight ratio of the anionic surfactant to the etheramine surfactant being about 1:10 to about 1:1. Compositions of the invention have reduced injuriousness to skin and/or eyes than otherwise similar compositions lacking only the anionic surfactant.

Description

AQUEOUS CONCENTRATE PESTICIDAL COMPOSITIONS HAVING IMPROVED

DERMAL AND OCULAR SAFETY

FIELD OF THE INVENTION

The present invention relates to aqueous concentrate formulations containing a water- soluble pesticide or plant growth regulator useful in agriculture and other situations. Hereinafter the term "pesticide" is used for brevity to include plant growth regulators. The present invention more particularly relates to such formulations further containing a surfactant of the etheramine class that enhances efficacy of the pesticide but that imparts to the aqueous concentrate an undesirable degree of injuriousness in the event of accidental contact with the skin and/or eyes of a person handling the aqueous concentrate. The present invention reduces or overcomes such injuriousness while at least maintaining the high degree of efficacy imparted to the pesticide by the etheramine surfactant.

BACKGROUND OF THE INVENTION

Water-soluble pesticides, including without restriction herbicides, fungicides, insecticides, acaricides, nematicides and plant growth regulators, are conveniently formulated as aqueous concentrates, wherein the pesticidal active ingredient is present in concentrated aqueous solution. A "concentrate" herein is a composition having an active ingredient concentration greater than about 50 g/1, up to the limit of solubility of the active ingredient in water; where the active ingredient is a salt of a pesticidally active acid, the lower limit of about 50 g/1 is to be understood to relate to the concentration of the active ingredient expressed as acid equivalent (a.e.). An "aqueous concentrate" herein is a liquid concentrate having a single phase that is an aqueous solution of the pesticide, or having a continuous phase that is an aqueous solution of the pesticide and one or more discontinuous phases that are other than aqueous, e.g., an oil-in-water emulsion, an aqueous suspension concentrate or a suspoemulsion. Aqueous concentrates are diluted in a suitable volume of water by the end-user and the resulting diluted composition is applied most commonly by spraying.

Particularly where the pesticide is to be applied to foliage of plants such as crops or weeds, it is common for the aqueous concentrate to contain one or more surfactants. Surfactants assist in retention on the foliage of droplets of the applied spray, adhesion of the spray droplets to the foliar surface and penetration of the water-soluble pesticide through the hydrophobic cuticle that covers the foliar surface, by these means and possibly in other ways enhancing biological effectiveness of the pesticide. A particularly useful class of surfactants providing enhanced biological effectiveness is described herein by the generic term "etheramine". Compositions of certain etheramine surfactants with the herbicide glyphosate or its salts are disclosed in U.S. Patent No. 5,750,468 to Wright.

Etheramine surfactants are compounds having, when present in an aqueous medium at a pH of about 4, the chemical formula (I)

where R¹ is a C_{6- 2} linear or branched, saturated or unsaturated aliphatic hydrocarbyl group, R² and R³ groups are independently C₂. alkylidene groups, m is an average number of 1 to about 5, x and y are average numbers such that x+y is an average number of 0 to about 60, R⁴ groups are independently hydrogen, Cι_-4 alkyl or benzyl groups, R⁵ is hydrogen, a C_1-4 alkyl or benzyl group or an anionic moiety selected from oxide (-O^") and -R⁶-COO^" groups wherein R⁶ is C_1- alkylidene, t is 1 or 2, A^t_ is a suitable anion, and v is 1 except where R⁵ is an anionic moiety in which case v is 0.

Etheramine surfactants of formula (I) above in which R⁵ is hydrogen are herein generally referred to as "tertiary etheramines" (an exception is where x and y are 0 and each R⁴ group is hydrogen, giving a primary etheramine). At some pH level higher than 4, for example at a pH of about 8, the nitrogen atom of such a tertiary etheramine is typically non-protonated and the tertiary etheramine, having no anion A^1" associated with it, can be described by the chemical formula (II)

(R³-O)_x-R⁴

where R¹, R², R³, R⁴, m, x and y are as defined for formula (I) above. Etheramine surfactants of formula (I) above in which R⁵ is a Cι_-4 alkyl or benzyl group are herein generally referred to as "quaternary etheramines" (an exception is where x and y are 0 and each R⁴ group is hydrogen, giving a secondary etheramine). Etheramine surfactants of formula (I) above in which R⁵ is an anionic moiety and v is 0 are herein generally referred to as "amphoteric etheramines" and include "etheramine oxides" (where R is -O^") and "etherbetaines" (where R⁵ is -CH₂-COO^").

Many surfactants having amine functions, when present in an aqueous concentrate pesticide composition at concentrations giving useful enhancement of pesticidal efficacy, unfortunately impart to the composition an undesirable degree of injuriousness in the event of accidental contact with the skin and/or eyes of a person handling the composition. Regulations governing pesticide labelling in the United States and a number of other countries are such that injuriousness to skin and/or eyes due to presence of a surfactant in a pesticide formulation can result in restrictions on the use of such a formulation.

U.S. Patent No. 5,703,015 to Berger et al. ("the '015 patent") discloses that eye irritancy of an aqueous concentrate pesticide composition due to presence therein of a polyoxyalkylene alkylamine surfactant can be reduced by inclusion in the composition of an acidic surfactant having a C_8-2o alkyl or alkylphenyl group. Specific classes of acidic surfactants disclosed to be useful are polyoxyalkylene alkylphenol sulfates, alcohol sulfates, polyoxyalkylene alcohol sulfates, mono- and dialcohol phosphates, mono- and di(polyoxyalkylene alcohol) phosphates, mono- and di(polyoxyalkylene alkylphenol) phosphates, polyoxyalkylene alkylphenol carboxylates and polyoxyalkylene alcohol carboxylates. The amount of acidic surfactant relative to the amount of polyoxyalkylene alkylamine surfactant appeared to have a strong bearing on the degree of eye irritancy reduction. For example, at a weight ratio of polyoxyethylene (4) nonylphenol phosphate to polyoxyethylene (16-17) tallowamine of about 1 :5.5 (Example 20 of the '015 patent) eye irritation remained at a relatively high level up to 21 days after exposure, whereas with the same total surfactant concentration but at a weight ratio of polyoxyethylene (4) nonylphenol phosphate to polyoxyethylene (16-17) tallowamine of about 1 :1.5 (Example 26 of the '015 patent) eye irritation had fallen to a low level by 7 days after exposure. U.S. Patent No. 5,389,598 to Berk et al. discloses that alkyl mono- and dicarboxylic acids are also effective in reducing eye irritancy of pesticide compositions containing a polyoxyalkylene alkylamine surfactant.

SUMMARY OF THE INVENTION It has now been found that certain etheramine surfactants can impart to an aqueous concentrate composition comprising a water-soluble pesticide an undesirable level of injuriousness to skin and/or eyes. This injuriousness can take the form of one or more of several adverse effects, including eye irritation, skin irritation and skin sensitization.

There is now provided a solution to the problem of such injuriousness to skin and/or eyes. According to the present invention, an aqueous concentrate pesticidal composition is provided, comprising (a) a water-soluble pesticide in an amount of about 50 to about 500 g/1; (b) an etheramine surfactant of formula (I) in an amount sufficient, if it were the sole surfactant present, to increase the level of injuriousness of the composition to skin and/or eyes; and (c) an anionic surfactant having the chemical formula (III) R⁷-(0-R⁸)_n-0-X where R⁷ is a C_4-22 linear or branched, saturated or unsaturated, aliphatic hydrocarbyl or a (C_8-ι₂ alkyl)phenyl group, R⁸ groups are independently C _-4 alkylidene groups, n is 0 to about 60 and X is an anionic radical selected from carboxylate, ether carboxylate, sulfate and phosphate; the weight ratio of the anionic surfactant to the etheramine surfactant being about 1 : 10 to about 1 : 1. Also provided is a method of reducing the injuriousness to skin and/or eyes of an aqueous concentrate pesticidal composition that comprises (a) a water-soluble pesticide in an amount of about 50 to about 600 g/1, and (b) an etheramine surfactant of formula (I); said method comprising addition to the composition of an anionic surfactant of formula (III) in a weight ratio of the anionic surfactant to the etheramine surfactant of about 1 : 10 to about 1 :1. In a preferred embodiment of the invention the etheramine surfactant is a tertiary etheramine of formula (II).

In a particularly preferred embodiment of the invention the anionic surfactant is a mono(polyoxyethylene alkyl or alkylphenyl ether) phosphate, alternatively described as a phosphate mono(polyoxyethylene alkyl or alkylphenyl) ester, optionally accompanied by the corresponding phosphate diester. A composition of the invention exhibits a lower degree of eye irritation, skin irritation and/or skin sensitization than a corresponding composition having the same total surfactant concentration but having none of the anionic surfactant. A preferred composition of the invention exhibits a lower degree of eye irritation, skin irritation and/or skin sensitization than a corresponding composition having the same concentration of the etheramine surfactant but wherein the anionic surfactant is replaced entirely with water. The invention has been found to be of particular utility where the water-soluble pesticide is a salt of the herbicide glyphosate. DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to aqueous concentrate compositions, including formulations known in the art as soluble concentrates (SL), oil-in- water emulsions (EW), water- based suspension concentrates (SC) and suspoemulsions (SE). In all cases a water-soluble pesticide is present in solution in an aqueous phase of the composition. The concentration of the water-soluble pesticide is expressed herein on an active ingredient (a.i.) basis except where the active ingredient is a salt of a biologically active acid, in which case the concentration is expressed on an acid equivalent (a.e.) basis. The concentration of pesticide (a.i. or a.e. as appropriate) in the composition as a whole ranges from about 50 to about 600 g/1; preferred compositions have a pesticide concentration of about 360 to about 540 g/1.

A "water-soluble" pesticide herein, including a salt or other water-soluble derivative of a pesticide, is one having a solubility in deionized water at 20°C of not less than about 50 g/1, more preferably not less than about 200 g/1.

Water-soluble fungicides and bactericides useful in compositions of the invention illustratively include borax, sec-butylamine, calcium polysulfide, copper sulfate, fosetyl, guazatine, hydroxyquinoline sulfate, iminoctadine, kasugamycin, mercuric chloride, metam, nabam, polyoxin B, propamocarb and validamycin and/or water-soluble salts thereof. Water- soluble insecticides, acaricides and nematicides useful in compositions of the invention illustratively include acephate, butoxycarboxim, cartap, dicrotophos, formetanate, hydrogen cyanide, methamidophos, methomyl, mevinphos, monocrotophos, nicotine, nitenpyram, omethoate, oxamyl, oxydemeton-methyl, phosphamidon, thiocyclam, trichlorfon and vamidothion and/or water-soluble salts thereof. Water-soluble plant growth regulators useful in compositions of the invention illustratively include chlormequat, chlorphonium, clofencet, cloxyfonac, cyanamide, daminozide, dikegulac, ethephon and mepiquat and/or water-soluble salts thereof.

In one embodiment of the invention, the water-soluble pesticide is a herbicide or an agriculturally acceptable salt thereof, including without restriction salts of acifluorfen, asulam, benazolin, bentazon, bialaphos, bromacil, bromoxynil, chloramben, clopyralid, 2,4-D, 2,4-DB, dalapon, dicamba, dichlorprop, diclofop, difenzoquat, diquat, endothall, fenac, fenoxaprop, flamprop, fluazifop, fluoroglycofen, fomesafen, fosamine, glufosinate, glyphosate, haloxyfop, imazameth, imazamethabenz, imazamox, imazapic, imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB. mecoprop, methylarsonic acid, naptalam, nonanoic acid, paraquat, picloram, sulfamic acid, 2,3,6-TBA, TCA and triclopyr.

Preferred water-soluble herbicides are salts of acid compounds whose molecular structure comprises at least one of each of amine, carboxylate, and either phosphonate or phosphinate functional groups. This category includes salts of the herbicides N-phosphonomethylglycine (glyphosate) and DL-homoalanin-4-yl(methyl)phosphinate (glufosinate). Another preferred group of herbicides are salts of compounds of the imidazolinone class, including imazameth, imazamethabenz, imazamox, imazapic, imazapyr, imazaquin and imazethapyr.

Where the herbicide is cationic or forms cations in the presence of an acid, as for example in the case of difenzoquat, diquat or paraquat, suitable counterions forming an agriculturally acceptable salt illustratively include chloride, bromide, iodide, sulfate, phosphate, acetate and succinate anions.

Where the herbicide is anionic or forms anions in the presence of a base, as for example in the case of most of the herbicides listed above with the exception of difenzoquat, diquat and paraquat, suitable counterions forming an agriculturally acceptable salt illustratively include sodium, potassium, ammonium, organic ammonium and organic sulfonium cations, wherein organic ammonium or organic sulfonium cations have from 1 to about 16 carbon atoms. Preferred organic ammonium cations are dimethylammonium, monoethanolammonium, n-propylammonium and isopropylammonium cations. Preferred organic sulfonium cations are trimethylsulfonium cations. Where the herbicide is glyphosate, especially preferred counterions are potassium and monoethanolammonium cations. It will be understood that more than one water-soluble pesticide can be present and that, in such a case, the concentration ranges given above apply to the total content of water-soluble pesticides in the composition. Optionally a composition of the invention can contain, in addition to one or more water-soluble pesticides, one or more pesticides of lower water solubility. If present, a pesticide of low water solubility is typically located primarily in a discontinuous non- aqueous phase of the composition, for example an oil phase of an oil-in-water emulsion or a solid particulate phase of a suspension concentrate.

As indicated above, a composition of the invention contains an etheramine surfactant having, when in an aqueous medium at a pH of 4, the chemical formula (I)

where R.¹¹ iiss aa CC _--2222 lliinneeaarr oorr bbrraanncchheedd,, ssaattuurra; ted or unsaturated aliphatic hydrocarbyl group, R² and R³ groups are independently C _-4 alkylidene groups, m is an average number of 1 to about 5, x and y are average numbers such that x+y is an average number of 0 to about 60, R⁴ groups are independently hydrogen, Cj_-4 alkyl or benzyl groups, R⁵ is hydrogen, a C_1-4 alkyl or benzyl group or an anionic moiety selected from oxide (-O^") and -R⁶-COO^" groups wherein R⁶ is C_1-4 alkylidene, t is 1 or 2, A^t_ is a suitable anion, and v is 1 except where R⁵ is an anionic moiety in which case v is 0.

In preferred etheramines, R¹ has at least about 8, more preferably about 12 to about 18 carbon atoms. All of the m (O-R²) units are preferably alike and are preferably ethylene oxide, isopropylene oxide or n-propylene oxide units. Where the (O-R²) units are ethylene oxide or propylene oxide units, m is preferably 1 to 5, most preferably 3 in the case of ethylene oxide units and most preferably 2 in the case of isopropylene oxide units. Where (O-R²) is n-propylene oxide, m is preferably 1. All of the x+y (R -O) units are preferably ethylene oxide, each of x and y is preferably at least 1, and x+y is preferably 2 to about 15, more preferably 2 to about 7. R⁴ groups are preferably hydrogen, except where x and y are 0, in which case R⁴ groups are preferably Cμ alkyl, more preferably methyl, groups. Where R³ is a C_1-4 alkyl or benzyl group, the surfactant is a quaternary etheramine, more correctly a quaternary etherammonium salt. In quaternary etheramines R³ is preferably a methyl group. The anion A^1" accompanying one or two etherammonium cations is preferably selected from chloride, bromide, iodide, sulfate, ethosulfate, phosphate, acetate, propionate, succinate, lactate, citrate and tartrate anions and is most preferably chloride. Illustrative examples of suitable quaternary etheramines are disclosed in above-cited U.S. Patent No. 5,750,468.

In a presently preferred embodiment of the invention, the surfactant is a tertiary etheramine corresponding to formula (I) wherein R⁵ is hydrogen. Note that formula (I) describes such a tertiary etheramine in its protonated form, as is typically present in an acidic aqueous medium. When protonated, the tertiary etheramine is accompanied by an anion A -, which again can illustratively be chloride, bromide, iodide, sulfate, phosphate, acetate, succinate or tartrate, but which, in the presence of an acidic pesticide, can be an anion of that pesticide, for example a glyphosate anion. In a neutral to basic aqueous medium, the tertiary etheramine is typically non- protonated and is more accurately described by the chemical formula (II)

(R³-O)_x-R⁴

where R . 1 , _n R2 , Γ R> 3 , _π R , m, x and y are as defined for formula (I) above. Illustrative examples of suitable tertiary etheramines are disclosed in above-cited U.S. Patent No. 5,750,468.

The concentration of etheramine surfactant in a composition of the invention is not narrowly critical, but is sufficient, in the absence of an anionic surfactant of formula (III), to cause an increased level of skin and/or eye injuriousness by comparison with an otherwise similar composition in which the etheramine surfactant is replaced by water. In particular, the concentration of etheramine is sufficient to increase the level of at least one injurious effect selected from eye irritation, skin irritation and skin sensitization, especially eye irritation and skin sensitization. Skin irritancy is believed to be a relatively rare property of etheramine surfactants. Nonetheless, dermal and ocular safety is a very important consideration with any pesticide product. Thus the present invention has utility for those compositions wherein the etheramine concentration is sufficiently high to have adverse impact on any aspect of such safety, even if such impact is slight.

It is preferred that the concentration of etheramine surfactant is sufficient to provide substantially improved biological efficacy of the pesticide when the composition is diluted in a suitable volume of water and applied to foliage of plants. Typically the weight ratio of etheramine surfactant to the water-soluble pesticide is about 1 :10 to about 2:1. Illustratively, where the water-soluble pesticide is a salt of glyphosate, the weight ratio of etheramine surfactant to glyphosate a.e. is preferably about 1 :9 to about 1:3.

Optionally, more than one etheramine surfactant can be present; in such a case amounts or concentrations given herein in relation to an etheramine surfactant are to be considered to apply to the total amount or concentration of etheramine surfactants present.

At the heart of the invention is the presence of an anionic surfactant having the chemical formula (III)

R⁷-(0-R⁸)_n-X where R⁷ is a C _-22 linear or branched, saturated or unsaturated, aliphatic hydrocarbyl or a (C_8-12 alkyl)phenyl group, R⁸ groups are independently C_2- alkylidene groups, n is 0 to about 60 and X is an anionic radical, selected from carboxylate (-COO^"), ether carboxylate (-OCH₂COO^"), sulfate (-OSO₃ ^") and phosphate (-OPO3H^" and -OPO₃ ^"). Surprisingly the anionic surfactant reduces the level of injuriousness of the composition to skin and/or eyes that is imparted by the etheramine surfactant. In particular, where the etheramine surfactant imparts or contributes to injuriousness in the form of eye irritation or skin sensitization, the injuriousness is moderated or eliminated by the presence of the anionic surfactant. According to one embodiment of the invention, replacement of a minor portion (not more than about one half) of the etheramine surfactant by an equal weight of the anionic surfactant improves dermal and/or ocular safety of the composition. According to another embodiment of the invention, addition of the anionic surfactant without reduction in the amount of etheramine surfactant present improves dermal and/or ocular safety of the composition.

The weight ratio of the anionic surfactant to the etheramine surfactant is not less than about 1 :10 and not greater than about 1 :1. Surprisingly, benefits in improved dermal and/or ocular safety are obtainable at low weight ratios of anionic surfactant to etheramine surfactant, for example about 1 : 10 to about 1 :4. Preferred weight ratios of anionic surfactant to etheramine surfactant are about 1 :8 to about 1:5.

Optionally, more than one anionic surfactant can be present; in such a case amounts or concentrations given herein in relation to an anionic surfactant are to be considered to apply to the total amount or concentration of anionic surfactants present.

Illustrative classes of anionic surfactant having utility in compositions of the invention include alkyl carboxylates such as fatty acids, polyoxyethylene alkyl ether carboxylates, polyoxyethylene alkylphenyl ether carboxylates, alkyl sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates (including those with ring sulfonation), mono- and dialkyl phosphates, mono- and di(polyoxyethylene alkyl ether) phosphates, mono- and di(polyoxyethylene alkylphenyl ether) phosphates, and salts thereof. Suitable cationic counterions in the case of such salts illustratively include sodium, potassium, ammonium, dimethylammonium, isopropylammonium, monoethanolammonium and trimethylsulfonium cations. The etheramine surfactant, in the form of etherammonium cations, can also form a salt with the anionic surfactant.

In preferred anionic surfactants, R⁷ in formula (III) is a (C_8-ι₂ alkyl)phenyl, e.g., octylphenyl, nonylphenyl or dodecylphenyl, or a C_8-22, more preferably C_12-18, linear or branched, saturated or unsaturated, aliphatic hydrocarbyl group. Suitable aliphatic hydrocarbyl groups include without restriction lauryl, myristyl, cetyl, palmitoleyl, stearyl, oleyl, linoleyl, linolenyl and isotridecyl groups. Conveniently such aliphatic hydrocarbyl groups can be derived from natural oils or fats and comprise mixtures of fatty alkyl chains such as cocoalkyl and tallowalkyl chains. (The term "alkyl" as used in surfactant nomenclature does not necessarily indicate full saturation.)

(O-R⁸) units in formula (III) are preferably ethylene oxide units. The number of such units (n) is preferably 0 to about 10.

In a presently preferred embodiment of the invention, X in formula (III) is phosphate, and accordingly the anionic surfactant is a monoalkyl ether phosphate or a mono(alkylphenyl) ether phosphate. Such a phosphate monoester is generally accompanied by the corresponding diester; amounts or concentrations of phosphate ester surfactants recited herein are to be understood to apply to the total of mono- and diesters. Preferably the monoesteπdiester weight ratio is greater than about 1 :1, more preferably greater than about 2:1. In principle the phosphate surfactant can all be present as the monoester, but in practice it is difficult, and unnecessary, to ensure the absence of diester.

Inert or excipient ingredients other than water, the etheramine surfactant and the anionic surfactant can optionally be included in a composition of the invention. Such ingredients include surfactants other than those of formula (I) or formula (III), for example polyoxyethylene alkylamines, alkylammonium salts and nonionic surfactants such as polyoxyethylene alkylethers, polyoxyethylene alkylphenylethers, sorbitan esters and alkyl polyglycosides. Other optional excipient ingredients include oils, solvents, stabilizing agents, antifreeze agents and pour point depressants such as glycols, dyes, inorganic salts such as ammonium sulfate, fertilizers, foam moderating agents, thickeners, drift control agents, etc.

The present invention is not limited by the method used to assess any aspect of injuriousness to skin or eyes, including eye irritation and skin sensitization. However, eye irritation can be assessed by means of the Draize test or a suitable modification thereof and skin sensitization by means of the Buehler test or a suitable modification thereof. Specific method protocols can be found in U.S. Environmental Protection Agency Pesticide Assessment Guidelines, Subdivision F, Guideline 81-4 (Draize test), and Guideline 81-6 (modified Buehler test).

EXAMPLES Compositions of Examples 1 and 2 hereinbelow all contain an etheramine surfactant of formula (II)

(R³-O)_x-R⁴

where R¹ is C_12-ι₄ alkyl, (O-R²) units are isopropylene oxide units, m is 2, (O-R³) units are ethylene oxide units, x+y is an average number of 5, and R⁴ is hydrogen. This surfactant is referred to in the Examples as Etheramine I.

Compositions of the invention illustrated in Examples 1 and 2 further contain an anionic surfactant that is a mixture of phosphate mono- and diesters of polyoxyethylene (4) isotridecyl ether in a weight ratio of about 7 parts monoester to 3 parts diester. This surfactant is referred to in the Examples as Phosphate I.

Composition A, included in Examples 1 and 2 as a comparative reference, is a water- soluble concentrate formulation of glyphosate isopropylammonium salt. It is prepared from MON 0139, a concentrated aqueous solution of glyphosate isopropylammonium salt having an assay of 46% glyphosate acid equivalent (a.e.). Ingredients (all percentages are by weight) of Composition A are:

MON 0139 (46.0% a.e.) 86.96%

Etheramine I 10.00% Deionized water 3.04%

The glyphosate a.e. concentration of Composition A is 40% by weight or 482 g/1. Composition A has a specific gravity (20/15.6°C) of 1.2053 and has a cloud point higher than 90°C, indicating excellent high temperature stability.

Composition B is a composition of the present invention having the following ingredients (all percentages are by weight):

MON 0139 (46.0% a.e.) 86.96%

Etheramine I 10.00%

Phosphate I 1.00%

Deionized water 2.04% The glyphosate a.e. concentration of Composition B is 40% by weight or 483 g/1.

Composition B has a specific gravity (20/15.6°C) of 1.2086 and has a cloud point of 77°C, indicating excellent high temperature stability.

Composition C is a composition of the present invention having the following ingredients (all percentages are by weight): MON 0139 (45.8% a.e.) 87.34%

Etheramine I 8.80%

Phosphate I 1.26%

Deionized water 2.60% The glyphosate a.e. concentration of Composition C is 40% by weight or 483 g/1. Composition C has a specific gravity (20/15.6°C) of 1.2076 and has a cloud point of 80°C, indicating excellent high temperature stability.

Composition D is a composition of the present invention having the following ingredients (all percentages are by weight):

MON 0139 (45.8% a.e.) 81.00%

Etheramine I 8.16%

Phosphate I 1.17%

Deionized water 9.67% The glyphosate a.e. concentration of Composition D is 37% by weight or 442 g/1.

Composition D has a specific gravity (20/15.6°C) of 1.1945 and has a cloud point of 74°C, indicating excellent high temperature stability.

In reading the Examples that follow, it should be understood that the eye irritation and skin sensitization effects evident for Composition A are entirely attributable to the surfactant component of that composition, MON 0139 itself being non-irritant to eyes and non-sensitizing to skin.

Example 1

Compositions A-D were tested for eye irritation by the Draize test following Guideline 81-4 of U.S. Environmental Protection Agency Pesticide Assessment Guidelines, Subdivision F. Compositions were administered in a single 0.1 ml dose, undiluted, to the conjunctival sac of the right eye of 6 New Zealand White rabbits. Corneal opacity, iris lesions and conjunctival redness, chemosis and discharge were each assessed at eight times after dose administration, on a standardized scale of 0-3, where 0 indicates no effect and 3 the most severe effect. Average scores were as shown in Tables 1-3. Table 1. Average corneal opacity scores

It should be noted that in the tests of this Example, treated eyes were not washed to remove the administered composition. Prolonged exposure effects shown above are not necessarily indicative of effects where, as is most likely, accidental contact of an irritant composition with the eye is followed within a short time by thorough washing to remove the irritant. Ocular injury as measured 1 hour after administration in the present tests is perhaps the most relevant indicator of potential injuriousness of a composition with washing of the eye. It will be noted that corneal and conjunctival injury 1 hour after administration was lower for Compositions B, C and D of the invention than for the reference standard Composition A. At later times, Composition B gave similar injury scores to Composition A, but Compositions C and D of the invention were markedly less injurious, showing improved recovery over a 21 -day period from the early effects of administration to the eye.

Example 2

Compositions A and D were tested for dermal sensitization by the modified Buehler test following Guideline 81-6 of U.S. Environmental Protection Agency Pesticide Assessment Guidelines, Subdivision F. An induction dose of 0.4 ml of each composition was administered undiluted to the clipped, intact skin of 10 albino guinea pigs using a Hilltop Chamber and occlusive dressing, once weekly for three weeks, for 6 hours each. A single challenge dose of 0.4 ml was administered undiluted to a naive skin site two weeks after the last induction dose, for 6 hours. A single rechallenge dose of 0.4 ml of a 50% dilution of the composition in deionized water was administered three weeks after the last induction dose, for 6 hours.

The results indicated that Composition A caused dermal sensitization, while Composition B did not cause dermal sensitization, in guinea pigs.

The preceding description of specific embodiments of the present invention is not intended to be a complete list of every possible embodiment of the invention. Persons skilled in this field will recognize that modifications can be made to the specific embodiments described here that remain within the scope of the present invention.

Claims

CLAIMS:

1. An aqueous concentrate pesticidal composition comprising

(a) about 50 to about 500 g/1 of a water-soluble pesticide;

(b) an etheramine surfactant having, when present in an aqueous medium at a pH of about 4, the chemical formula

where R^! is a C _-22 linear or branched, saturated or unsaturated aliphatic hydrocarbyl group, R² and R³ groups are independently C_2-4 alkylidene groups, m is an average number of 1 to about 5, x and y are average numbers such that x+y is an average number of 0 to about 60, R⁴ groups are independently hydrogen, Cj- alkyl or benzyl groups, R⁵ is hydrogen, a Cμ alkyl or benzyl group or an anionic moiety selected from oxide (-O^") and -R⁶-COO^" groups wherein R⁶ is C_]-4 alkylidene, t is 1 or 2, A^t_ is a suitable anion, and v is 1 except where R⁵ is an anionic moiety in which case v is 0; said etheramine surfactant being in an amount sufficient, if it were the sole surfactant present, to increase the level of injuriousness of the composition to skin and/or eyes; and (c) an anionic surfactant having the chemical formula

R⁷-(O-R⁸)_n-O-X where R⁷ is a C_4-22 linear or branched, saturated or unsaturated, aliphatic hydrocarbyl or a (C_8-12 alkyl)phenyl group, R groups are independently C_2-4 alkylidene groups, n is 0 to about 60 and X is an anionic radical selected from carboxylate, ether carboxylate, sulfate and phosphate; the weight ratio of the anionic surfactant to the etheramine surfactant being about 1 : 10 to about 1 :1.

2. The composition of Claim 1 wherein the etheramine surfactant is a tertiary etheramine having, when non-protonated, the chemical formula

(R³ -0)_x- -R⁴

where R¹ is a C_6-22 linear or branched, saturated or unsaturated aliphatic hydrocarbyl group, R and R groups are independently C_2-4 alkylidene groups, m is an average number of 1 to about 5, x and y are average numbers such that x+y is an average number of 0 to about 60, and R⁴ groups are independently hydrogen, C alkyl or benzyl groups.

3. The composition of Claim 2 wherein, in the formula for the tertiary etheramine, R¹ has about 12 to about 18 carbon atoms, (O-R ) units are ethylene oxide or isopropylene oxide units, m is 1 to 5, (R -O) units are ethylene oxide units, each of x and y is at least 1, x+y is

2 to about 15, and R⁴ groups are hydrogen.

4. The composition of Claim 1 wherein the weight ratio of the etheramine surfactant to the water-soluble pesticide is about 1 :10 to about 2:1.

5. The composition of Claim 1 wherein the anionic surfactant is selected from alkyl carboxylates, polyoxyethylene alkyl ether carboxylates, polyoxyethylene alkylphenyl ether carboxylates, alkyl sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates, mono- and dialkyl phosphates, mono- and di(polyoxyethylene alkyl ether) phosphates, mono- and di(polyoxyethylene alkylphenyl ether) phosphates, and salts thereof.

6. The composition of Claim 5 wherein the anionic surfactant is a mono(polyoxy ethylene alkyl or alkylphenyl ether) phosphate or mixture thereof with the corresponding di(polyoxyethylene alkyl or alkylphenyl ether) phosphate, or a salt of such phosphate or of such mixture of phosphates.

7. The composition of Claim 1 wherein the water-soluble pesticide is selected from borax, sec-butylamine, calcium polysulfide, copper sulfate, fosetyl, guazatine, hydroxyquinoline sulfate, iminoctadine, kasugamycin, mercuric chloride, metam, nabam, polyoxin B, propamocarb, validamycin, acephate, butoxycarboxim, cartap, dicrotophos, formetanate, hydrogen cyanide, methamidophos, methomyl, mevinphos, monocrotophos, nicotine, nitenpyram, omethoate, oxamyl, oxydemeton-methyl, phosphamidon, thiocyclam, trichlorfon, vamidothion, chlormequat, chlorphonium, clofencet, cloxyfonac, cyanamide, daminozide, dikegulac, ethephon, mepiquat, acifluorfen, asulam, benazolin, bentazon, bialaphos, bromacil, bromoxynil, chloramben, clopyralid, 2,4-D, 2,4-DB, dalapon, dicamba, dichlorprop, diclofop, difenzoquat, diquat, endothall, fenac, fenoxaprop, fiamprop, fluazifop, fluoroglycofen, fomesafen, fosamine, glufosinate, glyphosate, haloxyfop, imazameth, imazamethabenz, imazamox, imazapic, imazapyr, imazaquin, imazethapyr, ioxynil, MCPA, MCPB, mecoprop, methylarsonic acid, naptalam, nonanoic acid, paraquat, picloram, sulfamic acid, 2,3,6-TBA, TCA, triclopyr and salts thereof.

8. The composition of Claim 1 wherein the water-soluble pesticide is a salt of the herbicide glyphosate.

9. The composition of Claim 8 wherein the water-soluble pesticide is the potassium salt of glyphosate.

10. The composition of Claim 8 wherein the water-soluble pesticide is the monoethanolammonium salt of glyphosate.

11. In an aqueous concentrate pesticidal composition comprising a water-soluble pesticide and an etheramine surfactant having, when present in an aqueous medium at a pH of about 4, the chemical formula

where R¹ is a C_6-22 linear or branched, saturated or unsaturated aliphatic hydrocarbyl group,

R and R groups are independently C_2-4 alkylidene groups, m is an average number of 1 to about 5, x and y are average numbers such that x+y is an average number of 0 to about 60, R⁴ groups are independently hydrogen, Cj_-4 alkyl or benzyl groups, R⁵ is hydrogen, a C alkyl or benzyl group or an anionic moiety selected from oxide (-O^") and -R⁶-COO^" groups wherein R⁶ is C_1- alkylidene, t is 1 or 2, A^t_ is a suitable anion, and v is 1 except where R⁵ is an anionic moiety in which case v is 0; the improvement comprising addition, at a weight ratio to the etheramine surfactant of about 1 : 10 to about 1 : 1 , of an anionic surfactant having the chemical formula

R⁷-(O-R⁸)_n-O-X where R is a C_4-22 linear or branched, saturated or unsaturated, aliphatic hydrocarbyl or a (C₈-i₂ alkyl)phenyl group, R groups are independently C_2- alkylidene groups, n is 0 to about 60 and X is an anionic radical selected from carboxylate, ether carboxylate, sulfate and phosphate.