Buturon
Buturon is a methylurea, phenylurea herbicide, used to control grassy weeds, largely on cereals. It is now considered obsolete, having been first released as Eptapur in 1962.
Buturon's HRAC classification is Group C, Group C2 or Group 5.
Soil behaviour
Buturon rapidly degrades in the environment, and is not persistent, though some metabolites are.Wheat metabolises about 25% of buturon after seven days. Nutrient deficient plants metabolise it significantly faster though. The main metabolite groups are carbamates, unstable products, a group containing p-chloroacetanilide and conjugates. Nutrient-deficiency also decreases absorption and translocation, which is conjectured to passively rely on the flow of water. Plant metabolism may occur independently in roots and shoots.
Buturon has low volatility.
Safety
In a trial on mice given high daily doses of buturon, 100 to 400 mg/kg/day, and for comparison the LD50 is 1791 mg/kg, buturon induced postimplantative loss and retardation of development at doses over 300 mg/kg/day, and a dose-dependent trend of cleft palate, wavy or fused ribs and hypoplasia of the upper jaw.Rats metabolise buturon within 4 days and remove 68% and 20% by urine and faeces respectively.
Usage
Buturon is usually sold as a wettable powder, to be applied on berry fruits, maize, vines, and cereals including wheat and barley, to control such weeds as spurge, annual meadow grass and foxtails.It has been sold under the tradenames Arisan, Basfitox and Eptapur.