Abstract: This paper focuses on the detection and quantitation of estrogen hormone in Baltimore’s watersheds. Baltimore is the largest city in the U.S. state of Maryland, and the 30th-most populous city in the United States. Baltimore’s drinking water primarily comes from three watersheds (Loch Raven, Prettyboy, and Liberty). Between 1999 and 2000, the U.S. Geological Survey sampled 139 surface waters throughout the U.S and they discovered that 80% of these waters contained endocrine disrupting chemicals (mostly estrogens). Fish, are changing sex due to exposure to excess estrogen.