The leaching behavior of aldicar among complex pollution system composed of surfactant SDBS and aldicarb

The leaching behavior of aldicarb among the complex pollution system compos ed of aldicarb and surfactant - sodium dodecylbenzenesulfonate (SDBS) was s tudied by soil column. Distilled water was used to simulate rain in order t o obtain the rainfall of 235 mm for each time. Three simulations were carri ed out successively to give 705 mm rainfall in all. The results of multi-st ep leaching experiment showed that compared with control column, SDBS can i ncrease the vertical distance of aldicarb moving and accelerate the leachin g. As the concentration of SDBS increased from 250 to 500 mg kg(-1) of soil , not only the leaching depth of aldicarb increased by 20 cm, but also belo w 10 cm depth in soil column the concentration of aldicarb at the same dept h increased obviously. This will enhance the danger of groundwater pollutio n. SDBS affected the leaching behaviour of aldicarb in soil by influencing its water solubility, adsorption capacity and degradation process. The mech anism of this complex effect has been discussed in this article.