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. 2020 Mar 4;192(4):212.
doi: 10.1007/s10661-020-8160-2.

Adsorption of phenylurea herbicides by tropical soils

Babatunde Kazeem Agbaogun  1 , Klaus Fischer  2
Affiliations

Adsorption of phenylurea herbicides by tropical soils

Babatunde Kazeem Agbaogun et al. Environ Monit Assess. .

Abstract

The distribution of pesticides in soils with consequences for their mobility, bioavailability and water contamination is mainly ruled by sorption processes. Such processes are seldom investigated in tropical soils. Thus, specific interactions between tropical soils and most pesticides are widely unknown. Furthermore, the question arises whether the same factors govern adsorption in tropical and temperate soils. Thus, the sorption behaviour of five phenylurea herbicides (PUHs) was studied in eighteen differently composed soils originating from southwestern Nigeria. Sorption data were obtained by equilibrating the soil samples with 0.01 M CaCl2 solutions spiked with increasing concentrations of the target PUHs. The equilibrium data fitted well to the Freundlich isotherm equation (R2 ≥ 0.96), delivering the corresponding parameters (Kf and n). Linear distribution coefficients (Kd) were also calculated. The Pearson correlation was used to identify the specific soil and herbicide properties that have statistically significant correlations with sorption parameters. High correlations were established for various soil properties (pH, cation exchange capacity, organic carbon content, content of amorphous Fe and Mn oxides, clay/silt mass proportions) as well as molecular descriptors (octanol-water partition coefficient (log Kow) and molecular mass (Mw)) of the moderately hydrophobic herbicides. Monuron, chlorotoluron and isoproturon showed higher affinities for soil than previously reported. The gathered knowledge might assist in the assessment and in the precautionary avoidance of potential risks generated by these compounds in tropical soils.

Keywords: Adsorption; K f; Molecular descriptors; Phenylurea herbicides; Soil properties; Tropical soil.

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Figures

Fig. 1
Fig. 1
General structure of PUHs
Fig. 2
Fig. 2
Sorption kinetic profiles of a linuron, b diuron and c monuron
Fig. 3
Fig. 3
a Boxplots showing the mean Kf of the five compounds (the median is marked by the horizontal line inside the inner rectangle; the whiskers above and below the inner rectangle respectively represent the locations of the maximum and minimum, while the circles represent suspected outliers. b Charts of Kf and its trend with SOC
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References

    1. Agboola AA, Corey RB. The relationship between soil pH, organic matter, available phosphorus, exchangeable potassium, calcium, magnesium and nine elements in the maize. Journal of Soil Science. 1973;115:367–375.
    1. Baskeyfield DEH, Davis F, Magan N, Tothill IE. A membrane-based immunosensor for the analysis of the herbicide isoproturon. Analytica Chimica Acta. 2011;699(2):223–231. - PubMed
    1. Biscaye PE. Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent seas and oceans. Geological Society of America Bulletin. 1965;76:803–832.
    1. Blondel A, Langeron J, Sayen S, Henon E, Couderchet M, Guillon E. Molecular properties affecting the adsorption coefficients of phenylurea herbicides. Environmental Science and Pollution Research. 2013;20:6266–6281. - PubMed
    1. Chhokar RS, Singh S, Sharma RK. Herbicides for control of isoproturon resistant littleseed canarygrass (Phalaris minor) in wheat. Crop Protection. 2008;27:719–726.

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