USE OF HONEY MESQUITE AS A POTENTIAL PHYTOREMEDIATOR OF 2,4-DINITROTOLUENE (2,4-DNT): ELECTROANALYTICAL STUDIES
Julius Reyes, Martha Lopez.
University of Puerto Rico at Mayaguez, Mayaguez, PR.
The chemical 2,4-dinitrotoluene (2,4-DNT) is a precursor of the explosive trinitrotoluene (TNT), and it is widely used in the manufacturing of dyes, munitions, and plastics. Due to its common use, several sites around the world are contaminated with this chemical. Prosopis glandulosa, commonly known as mesquite, has been used in heavy metal phytoremediation. Mesquite produces large amounts of biomass, grows quickly, and has a large transpiration rate. Because of its deep root system, this plant may have the ability to accumulate other contaminants. The aim of the present work is to determine if mesquite is able to uptake and accumulate 2,4-DNT inside its tissues and to apply cyclic voltammetry as a complementary technique for the fast identification of 2,4-DNT. Mesquite plants were grown in a hydroponic system and exposed to 2,4-DNT at 1.0 x 10-3 M and 1.0 x 10-4 M. Extracts from roots, stems, and leaves were analyzed separately by cyclic voltammetry using a glassy carbon electrode (GCE). Extracts obtained from 2,4-DNT at 1 x 10-3 M treatment show higher peaks in the voltammogram revealing some interactions compared with voltammograms from control plants. Physical changes were observed in treated plants and compared with control plants. Chlorophyll content was measured in mesquite leaves from all treatments. Chlorophyll content in leaves from plants exposed to 2,4-DNT at 1.0 x 10-4 M was an average of 32.3 (± 8.1) and 18.2 (± 5.0) for plants exposed to 2,4-DNT at 1.0 x 10-3 M compared to 18.66 (± 13.1) in control plants. Further analysis will be done using high pressure liquid chromatography (HPLC) to quantify 2,4-DNT in plant extracts.