ДИКВАТ БРОМИД химические свойства, назначение, производство
Описание
Diquat (DQ) is a bipyridyl herbicide that has been in use since
the 1950s. It is employed as a general use herbicide that is fast
acting and nonselective. Additionally, on average, 90% of DQ
consumption is reported in North America, Europe, Australia,
and Japan.
Химические свойства
Pale yellow crystals; forms monohydrate; mp320°C (608 °F) (decomposes); readily solublein water, insoluble in organic solvents; stablein acids or neutral solution.
Использование
Diquat Dibromide is a herbicidal desiccant.
Угроза здоровью
The acute toxicity of diquat dibromide ismoderate to high in most species. In domes-tic animals, its toxicity is greater than thatin small laboratory animals. The oral LD50value in cows, dogs, rabbits, and mice is30, 187, 188, and 233 mg/kg, respectively.The symptoms of acute toxicity are somnolence, lethargy, pupillary dilation, and respiratory distress. Prolonged exposure to thiscompound produced cataracts in experimental animals. Intratracheal administration ofdiquat dibromide in rats showed toxic effectsin the lung and caused lung damage (Manabeand Ogata 1986). But when administered byoral or intravenous routes, there was no toxiceffect on the lung.
Профиль безопасности
Poison by ingestion,
subcutaneous, intravenous, and
intraperitoneal routes. Experimental
teratogenic and reproductive effects. A skin
and eye irritant. Human mutation data
reported. When heated to decomposition it
emits very toxic fumes of NOx, and Br-. See
also PARAQUAT
Экологическая судьба
Biological. Under aerobic and anaerobic conditions, the rate of diquat mineralization in eutrophic water and sediments was very low. After 65 days, only 0.88 and 0.21% of the applied amount (5 μg/mL) evolved as carbon dioxide (Simsiman and Chesters, 1976). Diquat is readily mineralized to carbon dioxide in nutrient solutions containing microorganisms. The addition of montmorillonite clay in an amount equal to adsorb one-half of the diquat decreased the amount of carbon dioxide by 50%. Additions of kaolinite clay had no effect on the amount of diquat degraded by microorganisms (Weber and Coble, 1968).
Photolytic. Diquat has an absorption maximum of 310 nm (Slade and Smith, 1967). The sunlight irradiation of a diquat solution (0.4 mg/100 mL) yielded 1,2,3,4-tetrahydro1-oxopyrido[1,2-a]-5-pyrazinium chloride (TOPPS) as the principal metabolite.
Chemical/Physical. Decomposes at 320°C (Windholz et al., 1983) emitting toxic fumes of bromides and nitrogen oxides (Lewis, 1990). Diquat absorbs water forming wellde?ned, pale yellow crystalline hydrate (Calderbank and Slade, 1976).
In aqueous alkaline solutions, diquat decomposes forming complex colored products including small amounts of dipyridone (Calderbank and Slade, 1976).
ДИКВАТ БРОМИД препаратная продукция и сырье
сырьё
препарат