Photodecomposition of endosulfan and related products in thin films by ultraviolet light irradiation

Abstract

hexahydro -6,9 -methano-2,4,3-benzodioxathiepin 3-oxide) isomers I and II in a thin film produced endosulfandiol as a major product. Endosulfan -hydroxy ether, lactone, ether, and an unknown No. 1 were additional photodecomposition products but in lesser amounts than the diol. Irradiation of endosulfandiol produced -hydroxy ether, unknowns No. 2 and 3. Irradiation of endosulfan ether gave the -hydroxy ether and the lactone. Irradiation of endosulfan a-hydroxy ether gave the ether and unknowns No. 2 and 3. Irradiation of endosulfan lactone resulted in less than 1 % each of the diol and the ether, but no -hydroxy ether was produced. The endosulfan sulfate was not a product from any of the irradiated compounds, and no degradation products were detected when it was irradiated with ultraviolet light. Derivatization of the diol and the -hydroxy ether by silylation and acetylation was necessary for the quantitation and identification of these two compounds within the photolysis mixtures. Photolysis of pesticides is important in the fate of these compounds in the environment and affects their toxicological characteristics. For example, Roburn (1963) found that grasses sprayed with dieldrin and exposed to sunlight under natural conditions for several months contained an unknown persistent compound. Dieldrin deposited as a film on glass plates and irradiated under a germicidal ultraviolet lamp (2537 A) was converted to some similar persistent compounds found on the grasses. The fact that strong

Photoactive TiO2Films Formation by Drain Coating for Endosulfan Degradation

“…The first endosulfan metabolite, sulfate endosulfan, was not detected, which agrees with the results of Archer et al [27] who noted that this compound was not identified as a photodecomposition product and that no degradation products were produced when it was irradiated.…”

Accumulation of Endosulfan in Wild Rat, Rattus norvegious as a Result of Application to Soya Bean in Mazoe (Zimbabwe)

“…Although sunlight may be involved in the initiation of sulphate production, thermolysis is the principle formation mechanism (Archer et al, 1972;Martens, 1977;Fig. 2).…”

Off‐Site Movement of Endosulfan from Irrigated Cotton in New South Wales

“…The formation of endosulfan sulfate in soil is carried out by fungi (Martens, 1977), microorganisms (Miles and Moy, 1979), and collembola (Park, 2000). Archer et al (1972) observed formation of nontoxic diol, ether, hydroxy‐ether, and lactone forms, after exposure of endosulfan to UV radiation. Hydrolysis in water also produces the diol (Peterson and Batley, 1993), and hydrolysis is faster in alkaline media, with half‐lives of the mixture being 28, 5.7, and 0.7 d at pH 5, 7, and 9 respectively (Southan and Kennedy, 1995).…”