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Prediction of Soil Sorption (Koc) of Herbicides Using Semiempirical Molecular Properties

Published online by Cambridge University Press:  12 June 2017

Krishna N. Reddy
Affiliation:
USDA-ARS, South. Weed Sci. Lab., Stoneville, MS 38776
Martin A. Locke
Affiliation:
USDA-ARS, South. Weed Sci. Lab., Stoneville, MS 38776

Abstract

Relationships between soil sorption normalized to organic carbon (Koc) and molecular properties of 71 herbicides were examined. The Koc values were obtained from the literature. Various molecular properties were calculated by quantum mechanical methods using molecular modeling software. The quantitative structure activity relationship (QSAR) models based on four molecular properties, van der Waals volume (VDWv), molecular polarizability (α), dipole moment (μ), and energy of highest occupied molecular orbital (eHOMO), together accounted for 70% of the variation in Koc. Herbicides were broadly divided into six families based on structural similarities, and separate equations were established for each group. The three descriptors, VDWv, α, and μ, along with either energy of lowest unoccupied molecular orbital (eLUMO), or electrophilic superdelocalizability (SE), or eHOMO appeared to be determinants and accounted for 82 to 99% of the variation in Koc. Applicability of these models was tested for one herbicide analogue and 10 metabolites. The QSAR models appear to be specific to structurally similar chemicals. The QSAR models could be developed to predict Koc of structurally similar compounds even before they are synthesized or for some of the metabolites of existing herbicides. Models of this type can also be developed to create priority lists for testing, so that time, money, and efforts can be focused on the potentially most hazardous chemicals.

Type
Soil, Air, and Water
Copyright
Copyright © 1994 by the Weed Science Society of America 

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References

Literature Cited

1. Briggs, G. G. 1981. Theoretical and experimental relationships between soil adsorption, octanol-water partition coefficients, water solubilities, bioconcentration factors, and the parachor. J. Agric. Food Chem. 29:10501059.Google Scholar
2. Brouwer, W. W. M., Boesten, J. J. T. I., and Siegers, W. G. 1990. Adsorption of transformation products of atrazine by soil. Weed Res. 30:123128.Google Scholar
3. Bruijn, J. D. and Hermens, J. 1990. Relationships between octanol/water partition coefficients and total molecular surface area and total molecular volume of hydrophobic organic chemicals. Quant. Struct.-Act. Relat. 9:1121.Google Scholar
4. Camilleri, P., Bowyer, J. R., Gilkerson, T., Odell, B., and Weaver, R. C. 1987. Structure-activity relationships in the Hill inhibitory activity of substituted phenylureas. J. Agric. Food Chem. 35:479483.Google Scholar
5. Dao, T. H. 1991. Field decay of wheat straw and its effects on metribuzin and S-ethyl metribuzin sorption and elution from crop residues. J. Environ. Qual. 20:203208.Google Scholar
6. Dewar, M. J. S., Zoebisch, E. G., Healy, E. F., and Stewart, J. J. P. 1985. AM1: A new general purpose quantum mechanical molecular model. J. Am. Chem. Soc. 107:39023909.Google Scholar
7. Domine, D., Devillers, J., Chastrette, M., and Karcher, W. 1992. Multivariate structure-property relationships (MSPR) of pesticides. Pestic. Sci. 35:7382.Google Scholar
8. Gustafson, D. I. 1989. Groundwater ubiquity score: A simple method for assessing pesticide leachability. Environ. Toxicol. Chem. 8:339357.CrossRefGoogle Scholar
9. Hickey, J. P. and Passino-Reader, D. R. 1991. Linear solvation energy relationships: “rules of thumb” for estimation of variable values. Environ. Sci. Technol. 25:17531760.Google Scholar
10. Kenaga, E. E. 1980. Predicted bioconcentration factors and soil sorption coefficients of pesticides and other chemicals. Ecotoxicol. Environ. Safety. 4:2638.Google Scholar
11. Kurtz, H. A., Stewart, J. J. P., and Dieter, K. M. 1990. Calculation of the nonlinear optical properties of molecules. J. Comp. Chem. 11:8287.Google Scholar
12. Leahy, D. E. 1986. Intrinsic molecular volume as a measure of the cavity term in linear solvation energy relationships: octanol-water partition coefficients and aqueous solubilities. J. Pharm. Sci. 75:629636.Google Scholar
13. Lewis, D. F. V. 1989. The calculation of molar polarizabilities by the CNDO/2 method: correlation with the hydrophobic parameter, log P. J. Comp. Chem. 10:145151.Google Scholar
14. Lyman, W. J. 1990. Adsorption coefficient for soils and sediments. Pages 4.14.33 in Lyman, W. J., Reehl, W. F., and Rosenblatt, D. H., eds. Handbook of Chemical Property Estimation Methods. 2nd ed. Am. Chem. Soc., Washington, DC.Google Scholar
15. Meylan, W., Howard, P. H., and Boethling, R. S. 1992. Molecular topology/fragment contribution method for predicting soil sorption coefficients. Environ. Sci. Technol. 26:15601567.Google Scholar
16. Nandihalli, U. B. and Rebeiz, C. A. 1991. Photodynamic herbicides. 9. Structure activity study of substituted 1,10-phenanthrolines as potent photodynamic herbicide modulators. Pestic. Biochem. Physiol. 40:2746:Google Scholar
17. Nandihalli, U. B., Duke, M. V., and Duke, S. O. 1992. Quantitative structure-activity relationships of protoporphyrinogen oxidase-inhibiting diphenyl ether herbicides. Pestic. Biochem. Physiol. 43:193211.Google Scholar
18. Nandihalli, U. B., Duke, M. V., and Duke, S. O. 1992. Relationships between molecular properties and biological activities of O-phenyl pyrrolidino- and piperidinocarbamate herbicides. J. Agric. Food Chem. 40:19932000.Google Scholar
19. Nandihalli, U. B., Duke, M. V., and Duke, S. O. 1993. Prediction of RP-HPLC log P from semiempirical molecular properties of diphenyl ether and phenopylate herbicides. J. Agric. Food Chem. 41:582587.Google Scholar
20. Reddy, K. N. and Locke, M. A. 1993. Molecular properties as predictors of Kow and Koc of phenylureas. Agron. Abstr. Am. Soc. Agron., Madison, WI. Page 46.Google Scholar
21. Sabljic, A. and Protic, M. 1982. Relationship between molecular connectivity indices and soil sorption coefficients of polycyclic aromatic hydrocarbons. Bull. Environ. Contam. Toxicol. 28:162165.CrossRefGoogle ScholarPubMed
22. Sabljic, A. 1983. Quantitative structure-toxicity relationship of chlorinated compounds: A molecular connectivity investigation. Bull. Environ. Contam. Toxicol. 30: 80–33.Google Scholar
23. Sabljic, A. 1984. Predictions of the nature and strength of soil sorption of organic pollutants by molecular topology. J. Agric. Food Chem. 32:243246.CrossRefGoogle Scholar
24. Sabljic, A. 1987. On the prediction of soil sorption coefficients of organic pollutants from molecular structure: Application of molecular topology model. Environ. Sci. Technol. 21:358366.Google Scholar
25. Sabljic, A. and Piver, W. T. 1992. Quantitative modelling of environmental fate and impact of commercial chemicals. Environ. Toxicol. Chem. 11:961972.Google Scholar
26. Simmons, K. A., Dixson, J. A., Hailing, B. P., Plummer, E. L., Plummer, M. J., Tymonko, J. M., Schmidt, R. J., Wyle, M. J., Webster, C. A., Baver, W. A., Witkowski, D. A., Peters, G. R., and Gravelle, W. D. 1992. Synthesis and activity optimization of herbicidal substituted 4-aryl-1,2,4-triazole-5(1H)-thiones. J. Agric. Food Chem. 40:297305.Google Scholar
27. Taft, R. W., Abraham, M. H., Famini, G. R., Doherty, R. M., Abboud, J. M., and Kamlet, M. J. 1985. Solubility properties in polymers and biological media 5: An analysis of the physicochemical properties which influence octanol-water partition coefficients of aliphatic and aromatic solutes. J. Pharm. Sci. 74:807814.Google Scholar
28. von Oepen, B., Kordel, W., Klein, W., and Schuurmann, G. 1991. Predictive QSPR models for estimating soil sorption coefficients: potential and limitations based on dominating processes. Sci. Total Environ. 109/110:343354.Google Scholar
29. Wauchope, R. D., Buttler, T. M., Hornsby, A. G., Augustijn-Beckers, P. W. M., and Burt, J. P. 1992. The SCS/ARS/CES pesticide properties database for environmental decision-making. Rev. Environ. Contam. Toxicol. 123:1164.Google Scholar