Effect of soil composition and dissolved organic matter on pesticide sorption

• Published in: The Science of the total environment Vol. 298; no. 1; pp. 147 - 161
• Main Authors: Spark, K.M., Swift, R.S.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 21.10.2002; Elsevier Science
• Subjects: Adsorption; Agronomy. Soil science and plant productions; Applied sciences; Biological and medical sciences; Biological and physicochemical properties of pollutants. Interaction in the soil; Carbon - chemistry; Earth sciences; Earth, ocean, space; Electrolytes; Engineering and environment geology. Geothermics; Environmental Monitoring; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Mineral content; Organic Chemicals; Organic matter state; Pesticides; Pesticides - chemistry; Pollution; Pollution, environment geology; Soil; Soil and sediments pollution; Soil and water pollution; Soil Pollutants - analysis; Soil science; Solubility; Sorption behaviour; Mineral content; Sorption behaviour; Organic matter state; Pesticides; Clay; Organic matter; 2,4-D; Pollutant behavior; Isoproturon; Mineralogy; Property of soil; Desorption; Soil pollution; Herbicide; Dissolved organic carbon; Adsorption; Medium effect; Aminoacid; Triazine derivatives; Paraquat; Ureas; Agriculture; Soil interaction; Phytohormone; Atrazine
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/S0048-9697(02)00213-9

The effect of the solid and dissolved organic matter fractions, mineral composition and ionic strength of the soil solution on the sorption behaviour of pesticides were studied. A number of soils, chosen so as to have different clay mineral and organic carbon content, were used to study the sorption of the pesticides atrazine (6-chloro- N 2-ethyl- N 4-isopropyl-1,3,5-triazine-2,4-diamine), 2,4-D ((2,4-dichlorophenoxy)acetic acid), isoproturon (3-(4-isopropylphenyl)-1,1-dimethylurea) and paraquat (1,1′-dimethyl-4,4′-bipyridinium) in the presence of low and high levels of dissolved organic carbon and different background electrolytes. The sorption behaviour of atrazine, isoproturon and paraquat was dominated by the solid state soil components and the presence of dissolved organic matter had little effect. The sorption of 2,4-D was slightly affected by the soluble organic matter in the soil. However, this effect may be due to competition for adsorption sites between the pesticide and the soluble organic matter rather than due to a positive interaction between the pesticide and the soluble fraction of soil organic matter. It is concluded that the major factor governing the sorption of these pesticides is the solid state organic fraction with the clay mineral content also making a significant contribution. The dissolved organic carbon fraction of the total organic carbon in the soil and the ionic strength of the soil solution appear to have little or no effect on the sorption/transport characteristics of these pesticides over the range of concentrations studied.