Hexazinone persistence

CASRN 51235-04-2 molecular formula C12H20N4O2 FW 252.30 Soil/Plant. Degrades in soil and natural waters releasing carbon dioxide. The reported half-life in soil is 1 to 6 months (Hartley and Kidd, 1987). Rhodes (1980) found that the persistence of hexazinone varied from 4 wk in a Delaware sandy loam to 24 wk in a Mississippi silt loam. 

Feng (1987) monitored the persistence and degradation of hexazinone in a silt loam soil 104 d after treatment of the herbicide. After 104 d, 66% of the hexazinone degraded via hydroxylation to form the major metabolite 3-(4-hydroxycyclohexyl)-6-(dimethylamino)-l-methyl-s-triazine-2,4(l//,3//)dione (30-50% yield). A minor metabolite, 3-cyclohexyl-6-(methylamino)-1-methyl-s-triazine-2,4(1//,3//)-dione, forming via demethylation, accounted for only 0-12% of the applied herbicide. Hexazinone and its metabolites were not detected in soils at depths of 15-30 cm. 

Feng, J.C. Persistence, mobility and degradation of hexazinone in forest silt loam soils, J. Environ. Scl Health, B22(2) 221-233, 1987. 

Roy. D.N.. Konar. S.K.. Charles. D.A.. Feng. J.C.. Prasad. R.. and Campbell. R.A. Determination of persistence, movement, and degradation of hexazinone in selected Canadian boreal forest soils. J. Agric. Food Chem., 37(2) 443-447. 1989. 

Fernandez, M.D., R.A. Perez, C. Sanchez-Brunete, and J.L. Tadeo (2001). Persistence of simazine and hexazinone in soil. Fresen. Environ. Bull., 10 490-494. 

Prasad, R. and J.C. Feng (1990). Spotgun-applied hexazinone Release of red pine (Pinus resinosa) from quaking aspen (Populus tremuloides) competition and residue persistence in soil. Weed Technol., 4 371-375. 

Solomon, K.R., Bowhey, C.S., Liber, K., Stephenson, G.R. (1988) Persistence of hexazinone (Velpar), triclopyr (Garlon) and 2,4-D in a northern Ontario aquatic environment. J. Agric. Food Chem. 36, 1314—1318. 

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