Dr. Cahill grew up in science as the son of a physics professor at the University of California, Davis, so there was little doubt that he would also end up in science. Childhood was full of plants, fossils, rocks and family vacations to National Parks. Family vacations were also frequently scheduled around Thomas Cahill Sr’s air sampling campaigns, such as the deployment of air samplers around Mount St. Helens in 1980 before it erupted. This resulted in some interesting trips. After graduating from high school, he enrolled in UC Davis as a Wildlife and Fisheries Biology major because of his love for the environment. His Masters degree was also at UC Davis measuring the impact of mercury in the birds of Clear Lake, California, which had a superfund site on the shores of the lake that had discharged mercury into the ecosystem. He measured mercury concentrations in the feathers of birds using x-ray fluorescence methodologies which allowed the bird species to be sampled in a non-invasive fashion. This was the genesis of his analytical chemistry skills being applied to an environmental problem.

After the Masters was complete, Dr. Cahill followed James Seiber, who was one of the early environmental toxicology professors, to the University of Nevada, Reno to quantify the concentrations of trifluoroacetic acid (TFA) in the ecosystem. The ozone depleting CFCs were being phased and replaced with hydrofluoroacrbons (HFCs), which could be degraded in the atmosphere to from TFA. TFA is exceptionally stable in the environment, so there were fears that it could accumulate in terminal water bodies and vernal pools. Dr. Cahill set about developing a new methodology to quantify TFA in water, soil and plant samples so that its impacts in vernal pools, which contain numerous endangered species in California. The analytical method sample extraction followed derivatization by sulfuric acid in methanol. This volatile derivative was the quantified by headspace gas chromatography. The results showed that TFA accumulated in terminal wetlands, and the plants growing in them, as expected. However, TFA is effectively a small, ionic chemical in the environment that was both highly water soluble and had low toxicity, so environmental impacts were minor at that time.