Occurrence and Transformation of Pharmaceutical and Antibacterial Compounds in the Environment

Abstract

The presence of pharmaceuticals and personal care products (PPCPs) in the environment has become a matter of concern during the last decade. Increased production of PPCPs along with their increased use has led to release of these compounds in the environment via various routes. PPCPs includes large group of compounds including veterinary and human antibiotics, analgesics and anti-inflammatory drugs, psychiatric drugs, β-blockers, X-ray contrasts, and steroid hormones, etc. Many of the compounds used in PPCPs have been shown to possess adverse effects to living organisms and act as endocrine disrupting agents (ECDs). This dissertation includes the investigation of the occurrence of antibiotic compounds added to personal care product and the transformation of hormones used in pharmaceuticals such as contraceptives. The results obtained in this study can provide information on the fate and transformation of the studied compounds once released in the environment.

An analytical method employing sonication extraction and HPLC-ESI-MS detection was developed. The developed method was used to detect antibiotic compounds triclosan (TCS) and triclocarban (TCC) in biosolids-applied soil and biosolids. Both TCS and TCC were detected at high concentrations in biosolids and at lower concentrations in biosolids-applied soil. TCS and TCC concentrations decreased in biosolids composts and in biosolids-applied soil collected at deeper depths. The developed method was able to provide efficient detection limits and reliable quantification of target compounds.

A molecularly imprinted polymer (MIP) was synthesized to achieve efficient clean-up of TCS and TCC from biosolids-applied soil and biosolids samples using 4,4’- DBP-4-vp-EGDMA. The motivation behind this project was to be able to eliminate the use of expensive instruments such as LC-MS and employ easily available instruments such as LC-UV. The synthesized MIP was able to achieve efficient clean-up and allowed quantification and identification of TCS and TCC in a complex matrix.

Transformation of hormones such as 17β-estradiol, estriol, ethynlestradiol, estrone and testosterone was studied by employing Fe (III)-saturated montmorillonite catalysts. The use of Fe (III) – saturated montmorillonite as a catalyst proved be to very efficient in transformation of the studied hormones. Complete removal of hormones was observed in aqueous environment. LC-UV was used for detection and quantification of hormones.