UPTAKE OF LAMBDA CYHALOTHRIN AND ATRAZINE BY AQUATIC MACROPHYTES IN A LABORATORY HYDROPONIC EXPOSURE

Phytoremediation is an efficient, inexpensive and a non-environmentally disruptive technique of cleaning up contaminated soils, water or air by using plants that are capable of containing, degrading or eliminating these contaminants. Using a 5% runoff model from a 0.65-cm rainfall event on a 2.02 hectare land, remediation capabilities of two common aquatic macrophytes in agricultural drainages of the Mississippi Delta, USA, were evaluated in a laboratory exposure. Atrazine, lambda-cyhalothrin and a combination of the two pesticides (combo) were hydroponically exposed to the macrophytes for 8, 24, 48 h and 5, 8 d. Upward translocation of atrazine was well displayed after 48h, but by 8d, the roots contained more of this pesticide than the upper plant tissue. Lambda-cyhalothrin was sequestered in the roots of both macrophytes; however translocation into upper biomass was not well exhibited. Higher lambda-cyhalothrin uptake was measured in J. effusus after 8d. In the combined pesticides exposure, atrazine was absorbed better than Lambda cyhalothrin. Chemical properties of pesticides should be considered prior to phytoremediation attempts. Water soluble chemicals such as atrazine are quickly absorbed and translocated by macrophytes in agricultural receiving systems while insoluble pesticides such as lambda-cyhalothrin may be sequestered into or adsorbed onto the roots of existing macrophytes.