Uptake of nitroaromatic compounds in plants : Implications for risk assessment of ammunition sites

The uptake of nitroaromatic compounds by plants from the soil was studied at an ammunition site. After the development of analytical methods for 2,4,6-trinitrotoluene, aminodinitrotoluenes and dinitrotoluenes in plant material, we could show that these substances accumulated in the roots of plants and are found to a lesser extent inleaves and stems. We observed only moderate differences between various plant species. It is likely that a metabolic transformation in plants leads to the formation of dinitrotoluenes which are considered to be potent carcinogens. Results from soils with a wide range of explosive concentrations show a good correlation between the plant and soil concentrations. The relative accumulation in plant material is higher at lower soil concentrations. At low soil concentrations of about 1 mg trinitrotoluene/kg soil, an accumulation factor of about 0.5 can be derived. These data are an important input for the risk assessment of ammunition sites.