Novel strategies for the study of emerging organic contaminants in the environment

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The presence of trace amounts of "emerging organic contaminants" (EOCs) in the aquatic environment such as pharmaceuticals and personal care products (PPCPs) is worrisome since mixture effects of these substances are not yet well understood. Moreover, the study of EOCs in aquatic and terrestrial environments presents new challenges due to their low concentration, diversity, unknown fate and lack of ecotoxicological data.*******My research program aims to find an answer to the following questions: What other EOCs of concern are present in the environment and at what concentrations? What are the biotransformation products of EOCs? Are mixtures of trace amounts of EOCs toxic to biota? In the next 5 years, we will focus on study of three classes of EOCs: 1) pharmaceuticals 2) cyanotoxins and 3) plastic additives. We plan to develop and apply a series of methods that will help us improve the study those EOCs in the environment.*******Objective #1: Improved extraction and separation techniques to identify EOCs by suspect screening****As many EOCs produced in large quantities may be found in the environment, new methodologies are required to cope with this diversity. Therefore, our work on this topic will improve sample preparation and chromatography to identify EOCs of diverse physicochemical properties by screening methods.****Objective #2: Study of biotransformation products of EOCs by electrochemical methods****Our research in this topic will make possible the development and application electrochemical techniques to generate phase I metabolites of EOCs in vitro. In addition, we will apply those techniques to identify metabolites of Lyngbya wollei toxins which will help us better understand their fate in surface waters.****Objective #3: New toxicity bioassay based on metabolic profiling of Daphnia magna****Our research in this topic aims to develop a new toxicity bioassay based on the analysis of metabolites in tissues of the water flea D. magna. We will use ecdysteroids and the crustacean juvenoid hormone as targets for quantitative studies that could indicate toxic effects in D. magna resulting from the exposure to mixtures of EOCs at environmental concentrations (< 10 ppb).*******The main contribution of my research program to the field of environmental chemistry in the next five years is the development and application of a series of new analytical and environmental toxicology methods that will make possible to study the toxicity of trace amounts of PPCPs and plastic additives, the study of transformation products of cyanotoxins and PPCPs well as the detection of new EOCs. In the long term, my research program will advance our knowledge about the presence, fate and toxicity of EOCs in the environment and will contribute to determine what contaminants are more concerning and where industry and government decision makers should concentrate their efforts in order to mitigate and control contamination.***