Method Development for the Determination of Suspected Endocrine Disrupting Compounds (EDCs) in SeawaterEPA Grant Number: U915975
Title: Method Development for the Determination of Suspected Endocrine Disrupting Compounds (EDCs) in Seawater
Investigators: Torres-Silva, Ivelisse
Institution: University of Puerto Rico, Central Administration
EPA Project Officer: Graham, Karen
Project Period: January 1, 2001 through January 1, 2004
Project Amount: $70,260
RFA: Minority Academic Institutions (MAI) Fellowships for Graduate Environmental Study (2001) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Academic Fellowships , Fellowship - Environmental Science
The determination of pollutants in seawater is an area that has not been well studied in environmental sciences. There is a need to know the levels of endocrine disrupting chemicals (EDCs) in the coasts of Puerto Rico because of the continuous release of sewage effluents with primary treatment. The objective of this research project is to develop and validate a methodology to study EDCs in seawater.
Solid phase microextraction (SPME) is being used as the extraction technique and gas chromatography/mass spectrometry for the chemical analysis. A polydimethylsiloxane/divinylbenzene 65µm fiber was better for the extraction of the EDCs standards studied from the model matrix in comparison with other fiber coatings. An extraction time of 45 minutes was determined from the extraction time profiles as well as practical limitations. Sample stirring was observed as an important parameter in SPME, in which 700 rpm was chosen in our research project. A 20-mL sample volume was chosen because of a marked increase in the extraction efficiency for most of the model compounds. Sample pH and glassware deactivation also were studied in this methodology. A decrease in extraction efficiency was observed when commercial humic substances were added to the model matrix. Natural humic material has been sampled from seawater at the coast of Cabo Rojo (El Faro) because this material is not commercially available and its properties are unique of the source of the material. Fourier transform infrared spectroscopy, H1 nuclear magnetic resonance spectroscopy, and ultraviolet infrared spectroscopy were acquired for the isolated fulvic and humic material. Also, an elemental analysis for some specific elements was performed. The effect of multiple samplings on the fiber was studied using scanning electron microscopy. A temperature effect will be studied in this methodology. Real samples will be taken and analyzed using the developed methodology.