Herbicide regulations

A broad-spectrum grass and broadleaf corn herbicide Regulated metabolites in groundwater include the parent, isoxaflutole (RPA 201772), and its metabolites RPA 202248 [2-cyclopropylcarbonyl-3-(2-methylsulfonyl-4-trifluoromethylphenyl)-3-oxopropanenitrile] and RPA 203328 (2-methanesulfonyl-4-trifluoromethylbenzoic acid)... 

Exposures to TCDD also resulted from industrial wastes or accidents that contaminated entire communities such as Times Beach, Missouri, and Seveso, Italy. Although TCDD is no longer commercially available, it remains a hazard for several occupations and occupants of certain geographical localities (Table 1-5). Cocaine abusers can encounter cocaine derived from coca plants treated with phenoxy herbicides in countries without herbicide regulation (Elsohly et al. 1984). 

CgHftCljOa- A selective growth regulator herbicide for use against broad-leaved plants. White solid m.p. I38°C. 

Recently, however, new interest has developed due to their chemotherapeutic and bacteriostatic usefulness in animal husbandry. They also have been patented as herbicides and plant-growth-regulating agents. 

The FDA has pubhshed methods for the deterrnination of residual solvents in spice extracts such as oleoresins and has limited the concentrations of those specific solvents that are permitted. Chlorinated hydrocarbons and benzene have been almost completely removed from use as extracting solvents in the United States their use continues overseas where toxicity regulations are less stringent. The presence of pesticides or herbicides in spices is rigidly controHed by the FDA. 

Herbicides are also sometimes classified according to mode of action, selectivity, registered uses, and toxicity. The ever-increasing importance of herbicides and other pesticides and agrochemicals to a wide range of users, regulators, and researchers has led to the development of multiple and extensive computer databases. The primary database resources contain collected information relevant to herbicides, and numerous resource pubHcations are available to those needing information on the various aspects of herbicides (2). 

The correlations between chemical descriptors of molecular properties and biological activity, especially the activity of herbicides and/or plant growth regulators has been described (12). Several alternatives or improvements on the Hansch-Fujita QSAR system have been developed (13—15). 

F = fungicide H = herbicide I = insecticide PGR = plant growth regulator. 

AIkyl-Ai,A/-diaLkyl-l-naphthalenecarboxamides are useful herbicides (86) and the 2,2-dimeth5lhydra2ide of 1-naphthalenecarboxyhc acid has been patented as a plant growth regulator (87). 2-Propynyl-2-naphthalenecarboxylate [53548-27-9] and similar esters are insecticides (88). 1-Naphthaleneacetic acid, the plant growth regulator, has been prepared from naphthalene, concentrated HCl, and paraformaldehyde without isolation of intermediate 1-chloromethylnaphthalene or l-naphthaleneacetonitnle (89). 

Reaction of / fZ-amyl alcohol with urea in the presence of sulfuric acid gives a monoalkylated urea (61,62). Monoalkyl ureas are used to prepare uracil derivatives which are useful as herbicides, fungicides, and plant growth regulators (61). 

In addition to conventional pesticides such as insecticides, herbicides, and fungicides, there are other chemicals classified as pesticides and regulated under FIFRA. These chemicals include wood preservatives, disinfectants (excluding chlorine), and sulfur. In the United States these chemicals have aimual usage of about 500,000 t, which is equal to conventional pesticides. 

Benzothiazolin-3-ylacetic acid, 4-chloro-2-oxo-as herbicide, 6, 328 as plant growth regulator, 1, 191 Benzothiazolium bromide, 2-methyl-3-propargyl-nucleating agent... 

Dithiazolidines S,S-dioxides as herbicides, 6, 944 as plant growth regulators, 6, 944 rearrangements, 6, 501-504... 

A pesticide is defined, under the Food and Environment Protection Act (1985), as any substance, preparation or organism prepared or used for destroying any pest . Pesticides include herbicides, fungicides, insecticides, molliiscicides, roden-ticides, growth regulators, and masonry and timber preservatives. 

The preparation of soils for crops, planting, and tilling raises dust as a fugitive emission. Such operations are shll exempt from air pollution regulations in most parts of the world. The application of fertilizers, pesticides, and herbicides is also exempt from air pollution regulations, but other regulations may cover the drift of these materials or runoff into surface waters. This is particularly true of the materials are hazardous or toxic. 

Before leaving the subject of polarity and in relation to uptake and distribution, mention should be made of weak acids and bases. The complicating factor here is that they exist in solution in different forms, the balance between which is dependent on pH. The different forms have different polarities, and thus different values. In other words, the values measured are pH-dependent. Take, for example, the plant growth regulator herbicide 2,4-D. This is often formulated as the sodium or potassium salt, which has high water solubility. When dissolved in water, however, the following equilibrium is established ... 

Herbicides, See also Pesticides, 160 Highly Flammable Liquids and Liquefied Petroleum Gas Regulations, 198, 199, 595 Hot work ... 

Acylanilides (abbreviated as anilides in this article) are generally used as selective pre- and/or post-emergence herbicides in paddy rice fields. The herbicidal activity of the anilides is similar to those exhibited by the auxin-like plant growth regulators. 

A.G. Hackett, Chloroacetanilides in Metabohc Pathways of Agrochemicals Part 1 Herbicides and Plant Growth Regulators, ed. T. Roberts, Royal Society of Chemistry, Cambridge, pp. 179-218(1998). 

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