DEACTIVATION, DISPOSAL AND MANAGEMENT OF AMITRAZ DIP-VATS

Authors: Hapeman, Cathleen; PIERPOINT, ANTHONY - U. MARYLAND; TORRENTS, ALBA - U. MARYLAND

Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/18/2002
Publication Date: 8/18/2002
Citation: N/A

Interpretive Summary:

Technical Abstract: Amitraz, N'-(2,4-dimethylphenyl)-N-(((2,4-dimethylphenyl)imino)methyl)-N-methylmethanimidamide, is an effective dip miticide for livestock. The kinetics and mechanisms of amitraz hydrolysis were examined so that effective vat management and waste disposal strategies could be developed. Hydrolysis afforded the acid-stable, 2,4-dimethylphenyl formamide and N-(2,4-dimethylphenyl)-N-methyl formamidine, both of which can be further hydrolyzed to 2,4-dimethylaniline. Ozonolysis was examined as a subsequent treatment for the more toxic aniline byproduct. The relative rate constants for the reaction of ozone were determined for several substituted anilines in aqueous solutions at pH 6.5 and 1.5. At pH 6.5, with the exception of m- and p-nitroaniline, the rate constants obey Hammett's equation. However, a linear plot of Hammett constants versus relative rate data at pH 1.5 showed poor correlation. Poor correlation was similarly observed for amine group atomic charge determinations, suggesting varied reaction mechanisms. Column studies conducted to determine the ability of ozone to degrade aniline on soil indicated that aniline was rapidly degraded under moist soil conditions, 5% (wt). Removal of 77-98% of [14C] aniline was observed from soil columns initially affording nitrosobenzene and nitrobenzene; further oxidation led to CO2.