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Photolysis of Aqueous Chlorimuron and Imazaquin in the Presence of Phenolic Acids and Riboflavin

Published online by Cambridge University Press:  12 June 2017

Ramarao Venkatesh
Affiliation:
Dep. Agron., Ohio State Univ. 2021 Coffey Road, Columbus, OH 43210
S. Kent Harrison
Affiliation:
Dep. Agron., Ohio State Univ. 2021 Coffey Road, Columbus, OH 43210
Mark M. Loux
Affiliation:
Dep. Agron., Ohio State Univ. 2021 Coffey Road, Columbus, OH 43210

Abstract

Laboratory experiments were conducted to determine the effect of three phenolic acids, acetone, and riboflavin on aqueous photolysis of chlorimuron and imazaquin. The phenolic acids investigated were caffeic acid (CA), ferulic acid (FA), and p-coumaric acid (PCA). Treatment solutions were contained in quartz vessels and irradiated with 300 to 400 nm UV light in a photoreactor. The extrapolated photolysis half-life of chlorimuron in pure solution was 107 h, compared to a half-life of 0.42 h for pure aqueous imazaquin. Chlorimuron in solutions containing 10 ppmw riboflavin, acetone, CA, FA, or PCA exhibited half-lives of 9, 57, 58, 67, and 146 h, respectively. Imazaquin in solutions containing 10 ppmw riboflavin, acetone, CA, FA, or PCA had half-lives of 0.70, 0.55, 0.55, 0.48, and 0.55 h, respectively. The presence of PCA in aqueous media delayed chlorimuron photolysis, whereas all other compounds, especially riboflavin, sensitized chlorimuron photolysis. In contrast, imazaquin photolysis was delayed in the presence of the test compounds, with riboflavin having the greatest effect and causing in a 68% increase in imazaquin half-life over that of imazaquin alone. Quantum yields for sensitized photolysis of chlorimuron by riboflavin and for riboflavin by imazaquin were 0.1134 and 0.0477, respectively. These results suggest that some soluble and naturally occurring organic compounds may enhance chlorimuron photolysis yet delay imazaquin photolysis in surface waters.

Type
Soil, Air, and Water
Copyright
Copyright © 1993 by the Weed Science Society of America 

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References

Literature Cited

1. Basham, G. W. and Lavy, T. L. 1987. Microbial and photolytic dissipation of imazaquin in soil. Weed Sci. 35:865870.CrossRefGoogle Scholar
2. Beyer, E. M. Jr., Duffy, M. J., Hay, J. V., and Schlueter, D. D. 1988. Sulfonylureas. Pages 117189 in Kearney, P. C. and Kaufman, D. D., eds. Herbicides: Chemistry, Degradation, and Mode of Action. Vol. 2. Marcel-Dekker, New York.Google Scholar
3. Burkhard, N. and Guth, J. A. 1976. Photodegradation of atrazine, atraton and ametryne in aqueous solution with acetone as a photosensitizer. Pestic. Sci. 7:6571.CrossRefGoogle Scholar
4. Cessna, A. J. and Muir, D.C.G. 1991. Photochemical transformations. Pages 199263 in Grover, R. and Cessna, A. J., eds. Environmental Chemistry of Herbicides. Vol. 2. CRC Press, Inc., Boca Raton, FL.Google Scholar
5. Choudry, G. G. 1984. Humic Substances: Structural, Photophysical, Photochemical, and Free Radical Aspects and Interactions with Environmental Chemicals. Gordon and Breach Scientific Publications, New York. Pages 158159.Google Scholar
6. Choudry, G. G., Roof, A.A.M., and Hutzinger, O. 1979. Mechanisms in sensitized photochemistry of environmental chemicals. Toxicol. Environ. Chem. Rev. 2:259302.Google Scholar
7. Crosby, D. G. 1969. Experimental approaches to pesticide photodecomposition. Residue Rev. 25:112.Google ScholarPubMed
8. Crosby, D. G. 1976. Herbicide photodecomposition. Pages 835890 in Kearney, P. C. and Kaufman, D. D., eds. Herbicides: Chemistry, Degradation, and Mode of Action. Vol. 2. Marcel-Dekker, New York.Google Scholar
9. Draper, W. M. 1985. Determination of wavelength-averaged, near UV quantum yields for environmental chemicals. Chemosphere 14:11951203.CrossRefGoogle Scholar
10. Draper, W. M. 1987. Measurement of quantum yields in polychromatic light: dinitroaniline herbicides. Pages 269280 in Zika, R. G. and Cooper, W. J., eds. Photochemistry of Environmental Aquatic Systems. ACS Symp. Ser. 327. Am. Chem. Soc. Google Scholar
11. Faust, B. C. and Hoigne, J. 1987. Sensitized photooxidation of phenols by fulvic acid and in natural waters. Environ. Sci. Technol. 21:957964.CrossRefGoogle ScholarPubMed
12. Hansen, J. R. and Buckholtz, K. P. 1952. Inactivation of 2,4-D by riboflavin in light. Weeds 1:237242.CrossRefGoogle Scholar
13. Loux, M. M., Liebl, R. A., and Slife, F. W. 1989. Availability and persistence of imazaquin, imazethapyr, and clomazone in soil. Weed Sci. 37:259267.CrossRefGoogle Scholar
14. Lykken, L. 1972. Role of photosensitizers in alteration of pesticide residues in sunlight. Pages 449469 in Matsumura, F., Boush, G. M., and Misato, T., eds. Environmental Toxicology of Pesticides. Academic Press, New York.CrossRefGoogle Scholar
15. Miller, G. C. and Zepp, R. G. 1983. Extrapolating photolysis rates from the laboratory to the environment. Residue Rev. 85:89110.Google Scholar
16. Mills, J. A. and Witt, W. W. 1989. Efficacy, phytotoxicity, and persistence of imazaquin, imazethapyr, and clomazone in no-till double-crop soybeans (Glycine max). Weed Sci. 37:353359.CrossRefGoogle Scholar
17. Neter, J., Wasserman, W., and Kutner, M. 1983. Applied Linear Regression Models. Richard D. Irwin, Inc., Homewood, IL. Pages 328376.Google Scholar
18. Owen, E. D. and O'Boyle, A. A. 1971. Photochemical reactions in rigid media—I. The effect of gelatin on the aerobic photochemistry of riboflavin in aqueous solution. Photochem. Photobiol. 14:683692.CrossRefGoogle ScholarPubMed
19. Renner, K. A., Meggitt, W. F., and Leavitt, R. A. 1988. Influence of rate, method of application, and tillage on imazaquin persistence in soil. Weed Sci. 36:9095.CrossRefGoogle Scholar
20. Sato, Y., Yokoo, M., Takahashi, S., and Takahashi, T. 1982. Biphasic photolysis of riboflavine with a low-intensity light source. Chem. Pharm. Bull. 30:18031810.CrossRefGoogle Scholar
21. Silber, J., Previtali, C., and Silbera, N. 1976. Photoreactions of riboflavin in the presence of 2,4-dichlorophenoxyacetic acid (2,4-D). J. Agric. Food Chem. 24:679680.CrossRefGoogle Scholar
22. Thomas, S. M. and Harrison, S. K. 1990. Surfactant-altered rates of chlorimuron and metsulfuron photolysis in sunlight. Weed Sci. 38:602606.CrossRefGoogle Scholar
23. Whitehead, D. C. 1964. Identification of p-hydroxybenzoic, vanillic, p-coumaric, and ferulic acids in soils. Nature 202:417418.CrossRefGoogle ScholarPubMed
24. Zepp, R. G. 1978. Quantum yields for reaction of pollutants in dilute aqueous solution. Environ. Sci. Technol. 12:327329.CrossRefGoogle Scholar
25. Zepp, R. G. 1982. Experimental approaches to environmental photochemistry. Pages 1941 in Hutzinger, O., ed. The Handbook of Environmental Chemistry. Vol. 2. Reactions and Processes. Springer-Verlag, New York.Google Scholar
26. Zepp, R. G. and Cline, D. M. 1977. Rates of direct photolysis in the aquatic environment. Environ. Sci. Technol. 11:359366.CrossRefGoogle Scholar