Contamination of surface and groundwater by neonicotinoids is a global problem and requires comprehensive action by individual countries in order to identify in detail the processes affecting the transport of these pesticides, their properties, and their harmfulness to the environment. The aim of this study was to assess the transport (expressed by sorption parameters) of selected neonicotinoids in the aquatic environment, using batch tests. Tests were carried out for acetamiprid individually and a mixture of five neonicotinoids (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam), for three different aquifer materials and quartz sand. Based on the obtained values of the sorption parameters, the greatest sorption of neonicotinoids was observed on soil with the highest content of organic matter and clay minerals content, while no sorption of these pesticides was observed on quartz sand. In addition, it was noticed that individual neonicotinoids undergo sorption to a different degree — thiacloprid was the most sorbed (R-value in the range 3.13–26.03), while thiamethoxam was the least (R-value in the range 1.89–8.41).
Knowledge of transport patterns of chemicals in groundwater is essential for environmental assessment of their potential impact. In the present study, the mobility of a chloride tracer injected into three different soils was investigated, using column experiments. The column tests were performed under steady-state conditions to determine parameters of chloride migration through soils. Based on breakthrough curves, pore-water velocity, dispersion coefficient and dispersivity constant were calculated for each soil sample using CXTFIT/STANMOD software. Pore-water velocity was in the range of 0.31 cm/min for fine sand, to 0.35 cm/min for silty sand and to 0.40 cm/min for vari-grained sand. The highest values of dispersion coefficient and dispersivity constant were observed for silty sand (0.55 cm2/min and 1.55 cm, respectively), while the lowest value was found for fine sand (0.059 cm2/min and 0.19 cm, respectively). Column experiments for chlorides (conservative tracer) are a preliminary stage for further research which will be undertaken to investigate migration parameters of selected neonicotinoids (reactive tracers) through different soils.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.