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To date, only a few studies on mobility and transport of antibiotics in soil exist. Alder et al. (2001) reported diffuse contamination of surface water after antibiotic leaching from agricultural soils. Examinations of ground water and leachate from fields with intensive livestock production and manuring detected none or only antibiotics in small numbers (Hirsch et al., 1999; Kemper et al., 2007). Column experiments showed,depending on the soil type, the retention of the adsorbing tylosin at different depths, while olaquindox, only weakly adsorbing, leached trough the columns and oxytetracycline was not transported at all into deeper soil segments as this compound is strongly adsorbed to soil (Rabølle and Spliid, 2000). For oxytetracyclines and tylosin, distribution coefficients in manure are smaller than in soils (Loke et al., 2002). A lowering effect of manure was also detected for sulphachloropyridazine: the distribution coefficient decreases with an increasing proportion of manure in soils, mainly due to the pH effect of alkalinicmanure (Boxall et al., 2002). For tetracyclines, a detection at soil depths of up to 30 cm over long time periods was described by Hamscher et al. (2002). This data demonstrated that tetracyclines not only occur in significant amounts in soil after fertilisation with liquid manure, but also persist and accumulate in the environment. This strong binding to soil-organic matter is based on the ability of the tetracyclines to form complexes with double-charged cations, such as calcium, which occur in high concentrations in soil (Samuelsen et al., 1992).
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