Abstrato

Photodegradation Kinetics of Fenoxaprop-P-ethyl and Tepraloxydim in Various Aqueous Media and the Impact of Residues on the Growth of Fresh Water Green Alga (Pseudokirchneriella Subcapitata)

Velmurugan Pandiselvi, and Atmakuru Ramesh

Phototransformation of the herbicides fenoxaprop-p-ethyl and tepraloxydim in natural sunlight was investigated in Milli-Q water and in three different aqueous buffer solutions of pH 5.0, 7.0 and 9.0 at 1.0 μg/mL and 2.0 μg/mL levels. Aliquots of water samples were collected in predetermined intervals and analyzed by a validated HPLC-UV. The method has the limit of quantification 0.01 μg/mL. The influence of cations (Fe2+, Cu2+, Co2+, Ni2+, Mn2+ and Zn2+) and anions (SO42-, Cl-, ClO4-, CO3- and HCO3-) in the photolytic degradation process were studied by adding different concentrations of ions (10-1M, 10-2M and 10-3M) in Milli-Q water. The effect of aeration was also studied in water. A study in dark was conducted at 25°C to understand the hydrolytic behavior of the pesticides under sterile condition. Complete mineralization of residues was confirmed by LC-ESI-MS/MS. A study was conducted to know the impact of residues on the growth of fresh water green alga (Pseudokirchneriella subcapitata).