Dissolved Organic Matter Assisted Transport of Hormones Through An Agricultural Soil
Abstract
In the last years the disrupting activity of steroidal sex hormones like estrogens has been discussed for various ecosystems and even for human fertility. Once released into the environment, steroids pose a severe risk to fauna and man. After excretion of the relevant compounds or their metabolites by the target animals, the transition of biologically active substances via dung or manure onto soils and into the groundwa- ter cannot be excluded. Yet there is only little knowledge on the stability, degradation and transport pathways of steroids in soils. Just as little is known about the fate of anabolic steroids which are licensed as growth promotants for farm animals in many meat-exporting countries outside the EU (e.g. USA, Australia). We therefore studied the transport of Trenbolone-17 and Melengestrolacetate (MGA) with col- umn experiments employing aggregated agricultural field soil materials (Luvisol E and Bt horizons). The columns (14.6 cm in height, 4.7 cm in diameter) were perco- lated from bottom to top using a peristaltic pump. The mean volumetric flow rate was kept constant throughout the experiments at 20 ml h-1. Chloride was used as nonreac- tive tracer. The flow regime is controlled by two flow regions reflecting the dual mode pore size distribution of the aggregated soil material. Our results show that although the very high KOC values U Trenbolone: 24311 within the E-horizon; 21622 within
the Bt-horizon and MGA: 16708 within the E-horizon; 59459 within the Bt horizon - we observe a quick breakthrough of low concentrations of the hormones simultaneous with the non-reactive tracer chloride. This points to the fact that within aggregated field soil, the risk for deep seepage of low concentrations of hormones is high.- Publication:
-
EGS General Assembly Conference Abstracts
- Pub Date:
- 2002
- Bibcode:
- 2002EGSGA..27.6246J