Hydrogen sulfide (H2S) is a gas with a distinctive rotten egg smell that is widely found in the environment from volcanoes, sulfur springs, undersea vents, swamps, municipal sewers, and in crude petroleum and natural gas (1). H2S is toxic at high concentrations, but at very small amounts, it can help plants and our bodies in many ways, including the improvement of plant germination and drought resistance, protection against cardiovascular diseases, and stimulation of memory (2-9).