Assessment of the Occurrence and Potential Risks of Antibiotics and their Metabolites in South Florida Waters Using Liquid Chromatography Tandem Mass Spectrometry

Abstract

This dissertation, written by Venkata Reddy Panditi, and entitled Assessment of the occurrence and potential risks of antibiotics and their metabolites in South Florida waters using liquid chromatography tandem mass spectrometry, having been approved in respect to style and intellectual content, is referred to you for judgment.We have read this dissertation and recommend that it be approved. _______________________________________Rudolf Jaffe Finally, all the antibiotics detected in reclaimed and surface waters were investigated to assess the potential risk to the aquatic organisms. The surface water antibiotic concentrations that represented the real time exposure conditions revealed that the macrolide antibiotics, erythromycin, clarithromycin and tylosin along with quinolone antibiotic, ciprofloxacin were suspected to induce high toxicity to aquatic biota.Preliminary results showing that, among the antibiotic groups tested, macrolides posed the highest ecological threat, and therefore, they may need to be further evaluated with, long-term exposure studies considering bioaccumulation factors and more number of species selected. Overall, the occurrence of antibiotics in aquatic environment is posing an ecological health concern.

Online solid phase extraction liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) method for the determination of sucralose in reclaimed and drinking waters and its photo degradation in natural waters from South Florida

“…To date, FIU Biscayne Bay Campus receives reclaimed water from Miami-Dade North District Waste Water Treatment Facility, which has a capacity to treat 380,000 m 3 /day of water. The capacity of the existing reuse system for FIU irrigation is 1.5 million gallons per day (MGD) for irrigating 40 acres of landscape [ 36 , 37 ]”.…”

Target and Non-target Techniques for the Quantitation of Drugs of Abuse, Identification of Transformation Products, and Characterization of Contaminants of Emergent Concern by High Resolution Mass Spectrometry

“…3.1) for the identification of metabolites of antibiotics in reclaimed waters. Acetyl-sulfamethoxazole and desmethyl anhydroerythromycin was found as the major metabolite and theoretical fragments generated by FISh (from Mass Frontier) provided a good correlation with the observed MS/MS spectra from data dependent scan [38]. Because the success of pathway 2 may be related to analyte concentration and chromatographic separation a comparison was conducted using the same samples.…”