The photodecomposition of bromacil

Identification of sensitized photooxidation products of bromacil in water

“…Both in the El and Cl mass spectra a molecular peak at m/e 362 was observed, indicating the presence of III. DISCUSSION Moilanen and Crosby (1974) investigated the sunlight photodecomposition of I in water and found, after prolonged irradiation (4 months), only a dealkylated product, 5-bromo-6-methyluracil. The very low yield of the photoreaction product (2.2%) indicated that I is practically stable in sunlight.…”

“…The UV-light photodecomposition of I was investigated in aqueous solutions (Kearney et al, 1969) and in solid films (Jordan et al, 1965), however, without the identification of the photoreaction products. Experiments done in simulated natural conditions with solar radiation (Moilanen and Crosby, 1974) yielded only 2.2% of a single dealkylated photoproduct (5-bromo-6-methyluracil). Addition of dye photosensitizers to aerated aqueous solutions of I leads to a quantitative and fast sunlight photochemical reaction (Acher and Saltzman, 1979).…”

Reviews of Environmental Contamination and Toxicology

“…Bromacil (5-bromo-3-sec-butyl-6-methyluracil) (140) is very stable toward sunlight wavelengths (Moilanen and Crosby 1974), but the addition of dye photosensitizers like riboflavine (RB) or methylene blue (MB) to aerated aqueous solution of the herbicide leads to a quantitative and rapid photochemical Acher and Saltzman (1980). Reproduced by permission of American Society of Agronomy.…”

Use of quadrupole time‐of‐flight mass spectrometry to determine proposed structures of transformation products of the herbicide bromacil after water chlorination

“…Experiments simulating natural conditions by exposure of aqueous solutions to direct solar irradiation (summer) for 4 months yielded only 2.2% of a single dealkylated photoproduct, indicating that bromacil is very stable toward sunlight [8]. Acher et al [3] performed a comparative study of several oxidation methods of aqueous bromacil solutions.…”

“…The photodecomposition of bromacil has also been investigated in aqueous solutions (using a mercury vapor lamp with its main output at 254 nm) although the products were not identified. Experiments simulating natural conditions by the exposure of aqueous solutions to direct solar irradiation (summer) for 4 months yielded only 2.2% of a single dealkylated photoproduct, indicating that bromacil is very stable toward sunlight . Acher et al .…”