Herbicide phenoxy

The phenoxy-herbicide, 2,4-D, has been successfully bioremediated in a soil contaminated with such a high level of the compound (710 ppm) that it... 

Ether Cle va.ge, This is commonly observed as the initial step in the metaboHsm of the phenoxy herbicides 2,4-D (1), (2,4,5-trichlorophenoxy)acetic acid (2,4,5-T), and mecoprop (17). A wide variety of bacteria have been isolated which are able to catalyze this reaction (eq. 

The reaction is utili2ed in the synthesis of several phenoxy herbicides. 

Conversion of a nontoxic molecule to one that is toxic, or a molecule with low potency to one that is more potent. Examples include the formation of the phenoxy herbicide 2,4-D from the corresponding butyrate, formation of nitrosamines, and methylation of arsenicals to trimethylarsine. 

Kogevinas, M., H. Becher, T. Benn, PA. Bertazzi, P. Boffetta, H.B. Bueno-de-Mesquita, D. Coggon, D. Colin, D. Flesch-Janys, M. Fingerhut, L. Green, T. Kauppinen, M. Littorin, E. Lynge, J.D. Mathews, M. Neuberger, N. Pearce, and R. Saracci. 1997. Cancer mortality in workers exposed to phenoxy herbicides, chlorophenols, and dioxins. An expanded and updated international cohort study. Amer. Jour. Epidemiol. 145 1061-1075. 

Phenoxy herbicides, 10 520 Phenoxypropionic acid herbicides, 13 314 Phenoxy resins, 10 6, 364-365 Phentermine, 3 91... 

In contrast to the broad-spectrum herbicides, others are more selective. The phenoxy herbicides, which include chemicals such as 2,4-D, 2,4,5-T, and MCPA, are toxic to broad-leaf plants but do not affect narrow-leaf plants such as grasses. 

Altom, J.D. and Stritzke, J.F. Degradation of dicamba, picloram, and four phenoxy herbicides in soils, WeedSci., 21 556-560, 1973. 

D Acid 94-75-7 2.25 -1950 Herbicide A translocated phenoxy herbicide for use in cereals, grass, and amenity use... 

Massive Quantities of Phenoxy Herbicides in Test Grids, Field Plots, and Herbicide Storage Sites... 

The studies of soil residues and vegetative succession of Test Area C-52A confirmed that massive quantities of phenoxy herbicides rapidly disappeared following the termination of an aerial spray equipment testing program. 

To determine the soil persistence of the two phenoxy herbicides contained In Herbicide Orange and the dioxin contaminant. 

YOUNG Degradation Studies of Phenoxy Herbicides Discussion and Conclusions... 

In the biodegradation plots and In the Herbicide Storage Areas, high concentrations of herbicides were applied In a short time period and Incorporated Immediately Into the soil profile, and hence, the long persistence time. Nevertheless, these studies do show that the soil chemistry and the soil microbial populations can effectively combine to degrade massive concentrations of the phenoxy herbicides and that recovery of the sites occur as documented by the re-establlshment of the vegetative community. 

The addition of coconut charcoal Increases persistence of phenoxy herbicide residues, especially residues of 2,4,5-T. 

The contaminant 2,3,7,8-TCDD has a long persistence time In soils (years) and may be a major consideration In the use of soil biodegradation as a disposal option for "unwanted" phenoxy herbicides or TCDD-contamlnated chemical wastes. 

I am indebted to Drs. Eugene Arnold and Mason Hughes for the analyses of the phenoxy herbicides, phenols and the TCDD contaminant. 

Winston, A. W. and R. M. Rltty, 1971. "What Happens to Phenoxy Herbicides When Applied to a Watershed Area."... 

Young, A. L., W. J. Calrney and C. E. Thalken, 1983. "Persistence, Movement and Decontamination Studies of TCDD In Storage Sites Massively Contaminated with Phenoxy Herbicides." Chemosphere 12(4/5) 713-726. 

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