Large quantities of the chemical oil dispersant Corexit were applied in the Gulf of Mexico (Gulf) in response to the Deepwater Horizon oil spill. Large data gaps regarding the potential transport, persistence and impact of Corexit in the Gulf existed at the time of the emergency response. Analytical methods for...
Research and public concern of poly and perfluoroalkyl substances (PFASs) as environmental contaminants has increased significantly due to the increasing number of reports of their detection in humans and wildlife. PFASs have a number of commercial applications including surfactants, coatings, polymers, and levelers, which are used on consumer products like...
Wastewater epidemiology is an emerging discipline that requires collaborative research involving analytical chemists, drug epidemiologists, and wastewater engineers. Wastewater epidemiology involves the sampling and quantitative analysis of raw wastewaters from communities for illicit drugs and their metabolites. Mass loads (mass per day) and per capita (mg per day per person)...
The development of analytical methods for emerging contaminants creates many unique challenges for analytical chemists. By their nature, emerging contaminants have inherent data gaps related to their environmental occurrence, fate, and impact. This dissertation is a compilation of three studies related to method development for the structural identification of emerging...
A sensitive, selective, rapid analytical method based on large-volume injection (LVI)
liquid chromatography/ tandem mass spectrometry was developed using
commercially-available hardware that eliminates the need for either off-line or on-line
solid phase extraction. Centrifugation followed by the direct injection of 1,800 µL
was used for the quantification of illicit drugs,...
Capstone 1157 is a commercial reference material used in aqueous film forming foam (AFFF) applications and was manufactured by DuPont. The material’s purpose in this project was to be the sole carbon source to microbes in a biodegradation study in a microcosm environment. The goal of this project was to...
Per- and polyfluoroalkyl substances (PFAS) are a group of anthropogenic compounds that are used ubiquitously in different industrial fields. However, concerns regarding the potential health impacts of PFAS, including perfluoroalkyl carboxylic acids
(PFCAs) and perfluoroalkyl sulfonates (PFSAs), has raised stakeholder interest regarding continued use of PFAS. Analytical methods for PFAS...
Aqueous film-forming foams (AFFFs) are significant sources of per- and polyfluoroalkyl substances (PFAS) in the environment. Current analytical methods that provide quantitative measures of individual PFAS in AFFFs, such as liquid chromatography – tandem mass spectrometry (LC-MS/MS), are often complicated, time-consuming, and expensive. Methods for total fluorine analysis, though quantitative,...
The presence of per- and polyfluoroalkyl substances (PFAS), organic contaminants first synthesized in the 1940s, has been reported worldwide in a variety of environmental matrices and ultimately in biological systems including humans. Ongoing research into PFAS has included identifying novel PFAS, assessing their fate and transport in the environment, and...
Per- and polyfluoroalkyl substances (PFAS) are anthropogenic surfactants that have recently been identified as persistent organic pollutants. These so called “Forever Chemicals” have been detected in drinking waters, ground waters, soils, and consumer and industrial products globally; with environmental impacts stretching into the artic, far from known PFAS sources. The...