Atrazine properties

A. Bronshtein, N. Aharonson, D. Avnir, A. Turniansky, and M. Altstein, Sol-gel matrixes doped with atrazine antibodies atrazine binding properties. Chem. Mater. 9, 2632-2639 (1997). 

Chung N, Alexander M (1998) Differences in sequestration and bioavailability of organic compounds aged in dissimilar soils. Environ Sci Technol 32 855-860 Chung N, Alexander M (2002) Effect of soil properties on bioavailability and ex-tractability of phenanthrene and atrazine sequestered in soil. Chemosphere 48 109-115... 

In recent studies, pesticides such as atrazine have been found in precipitation. Therefore volatilization and subsequent transport in the gaseous phase is an important environmental pathway. Vaporization rates of pesticides deposited on surface of soil and plant leaves depend on the physical-chemical properties of the substance. A useful physicochemical criterion is Henry s constant, Ku, which is defined as the equilibrium air-to-water partial pressure ratio of the substance (see Chapter 7). 

Fig. 8.31 Adsorption isotherms of terbuthylazine and atrazine at different depths along the soil profile, as affected by the vertical variability of soil properties. (Dror et al. 1999)...

Atrazine, a triazlne compound, is extensively used as a selective herbicide on corn and sorghum fields for the control of broadleaf and grassy weeds. Depending on soil properties and climatic effects, its persistence from recommended application rates in north central states may extend well beyond one year and crop injury may result when sensitive species are in the rotation (50). 

Studies on sorption of triazines by individual soil constituents and by model sorbents have been very helpful in evaluating sorption mechanisms and in assessing the potential contribution of various constituents to triazine sorption by soils. However, intimate associations between organic substances, silicate clays, and oxyhydroxide materials modify the sorptive properties of the individual constituents. Associations between soil constituents influence soil properties - such as pH, specific surface area, and functional group availability - which in turn influence triazine sorption behavior. For instance, atrazine and simazine sorption behavior is different for synthetic mixtures of model soil... 

The type of clay present in a soil influences triazine sorption (Brown and White, 1969). Furthermore, variations in surface properties among different samples of the same clay type greatly influence sorption. For instance, sorption of atrazine on 13 clay samples, of which smectite was the dominant mineral, ranged from 0% to 100% of added atrazine (Figure 21.7), and was inversely correlated to the surface charge density of the smectites (Laird et al., 1992). Such data illustrate the complexity of sorption processes and the reason why simple predictive models relying on % OC, % clay, or surface area normalizations may fail to predict accurately the sorption of triazine by a particular soil. 

Dousset, S., C. Mouvet, and M. Schiavon (1997). Sorption of terbuthylazine and atrazine in relation to the physico-chemical properties of three soils. Chemosphere, 28 467-476. 

Studies on the properties of atzA are relevant for potential applications of this enzyme in removing atrazine from water and soil that require remediation. Atrazine is an effective herbicide, while hydroxyatrazine is nonphytotoxic and binds rapidly to soil. In this context, the first metabolic step carried out by Pseudomonas strain ADP represents the best possible step from an environmental standpoint. While the intact organism catalyzes atrazine hydrolysis and subsequent reactions, the enzyme could prove more efficacious for the following reasons ... 

The structures and other properties for simazine, propazine, prometryn, prometon, and other triazine herbicides and many of their degradation products can be found in the Appendices, Tables Al, A2 and A3. As shown in Figure 30.12, atrazine and simazine degrade to DIA. 

Many chemicals are regulated by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and their properties are as diverse as the properties of ecosystems. In forestry, however, relatively few herbicides are used very much. In fiscal year 1981, for instance, the USDA Forest Service used more than 25 different herbicides in the National Forests, but 2,4-D and picloram alone and in combination accounted for 70% of the total amount of herbicide applied. Atrazine, glyphosate, dalapon, simazine, fosamine, and hexazinone accounted for an additional 18% (2). 

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