Abiotic hydrolysis, sorbed

Abiotic hydrolysis, sorbed pesticides, 221-43 Acetanilide herbicide, groundwater contamination, 299 Acid-catalyzed hydrolysis aldlcarb by RIEX, 257f kinetics, disappearance rate, 223 Acid hydrolysis, sorbed pesticides, 242... 

It is the purpose of this article to summarize the present status of our understanding of the factors governing the rates of hydrolysis of pesticides which are sorbed to sediments. The work reported herein deals specifically with abiotic hydrolysis reactions, which for some pesticides, may be as important or more important than biologically mediated hydrolysis reactions (], . ... 

MACALADY AND WOLFE Abiotic Hydrolysis of Sorbed Pesticides... 

Coleman, K. D. 1988. Acid Catalyzed Abiotic Hydrolysis of Sorbed Pesticides, M.S. Thesis, Colorado School of Mines. 

Macalady, D. L., and N. L. Wolfe. 1984. Abiotic hydrolysis of sorbed pesticides, in ACS Symposium Series, No. 259 Treatment Disposal of Pesticide Wastes, Krueger, R. F., and J. N. Seiber, Eds., (Washington, DC American Chemical Society), pp. 221-244. 

The only available evidence in the literature which relates, though indirectly, to hydrolysis of sorbed pesticides concerns pesticides in soil systems (see for example 14, 15). Though the results of such studies are not directly applicable to aquatic systems, they do, in general, show that certain pesticides undergo abiotic reactions in soil-sorbed states. 

Oxidation-reduction (redox) reactions, along with hydrolysis and acid-base reactions, account for the vast majority of chemical reactions that occur in aquatic environmental systems. Factors that affect redox kinetics include environmental redox conditions, ionic strength, pH-value, temperature, speciation, and sorption (Tratnyek and Macalady, 2000). Sediment and particulate matter in water bodies may influence greatly the efficacy of abiotic transformations by altering the truly dissolved (i.e., non-sorbed) fraction of the compounds — the only fraction available for reactions (Weber and Wolfe, 1987). Among the possible abiotic transformation pathways, hydrolysis has received the most attention, though only some compound classes are potentially hydrolyzable (e.g., alkyl halides, amides, amines, carbamates, esters, epoxides, and nitriles [Harris, 1990 Peijnenburg, 1991]). Current efforts to incorporate reaction kinetics and pathways for reductive transformations into environmental exposure models are due to the fact that many of them result in reaction products that may be of more concern than the parent compounds (Tratnyek et al., 2003). 

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