Hi Reddit! Ask me anything about the chemistry of disinfecting water for swimming pools or other treatment needs!* I’m Susan D. Richardson, Ph.D., the Arthur Sease Williams Professor of Chemistry in the Department of Chemistry and Biochemistry at the University of South Carolina in Columbia, SC. Prior to coming to USC in January 2014, I was a research chemist for several years at the U.S. Environmental Protection Agency’s National Exposure Research Laboratory in Athens, GA. For the last several years, I’ve been conducting research in drinking water and in swimming pool water—specifically in the study of toxicologically important disinfection by-products (DBPs). These are the unintended consequence of trying to kill harmful microorganisms in drinking water and in pools. The disinfectants kill bacteria and contaminants that can cause deadly illnesses such as cholera, but they can interact with natural organic matter formed from decaying leaves and plants in rivers. Disinfectants like chlorine will react with that natural organic matter to form DBPs, that can in turn cause detrimental human health effects in drinking water, including bladder cancer, miscarriages, and birth defects. Pool DBPs have also been implicated in cases of asthma and bladder cancer. I work on identifying new DBPs or other unknown chemicals in the environment, drinking water, and pools using mass spectrometry. I also study wastewater treatment plants and the effects of disinfectants on river water. Most recently, I’ve started to investigate the impact of hydrofracking on DBPs in water. You can read about some of my newest research on DBPs in swimming pool and spa water in this Editor’s Choice open access article in Environmental Science & Technology and my work is also covered in a recent article from Chemical & Engineering News. My B.S. in chemistry and mathematics is from Georgia College & State University and my Ph.D. in chemistry is from Emory University. I also have an honorary doctorate from Cape Breton University in Canada and was recently named an ACS Fellow. I serve as an Associate Editor for Water Research, on the Editorial Advisory Board for Environmental Science & Technology, and write on emerging contaminants in water/environmental analysis for Analytical Chemistry. I’ll be on at 1pm EDT. I’m live now! I look forward to answering your questions! -sr