Health effects from chronic low level exposure include the burning and tearing of eyes, cough, shortness of breath, and for asthmatics, difficulty breathing. The effects may be delayed for several hours, or sometimes several days, when exposed to low level concentrations. Chronic exposure causes eye inflammation, headache, fatigue, irritability, insomnia, digestive disturbances and weight loss. Researchers found the following demonstrable symptoms resulting from chronic exposure to H2S: changes in brain density, abnormal neurobehavioral function, headache, altered mood states such as depression, fatigue, and tension, memory loss, pronounced deficits in balance and reaction time, dizziness, insomnia, overpowering fatigue, and reduced sense of smell.
EPA should address adverse H2S impacts based on evidence of harmful exposures in numerous communities and its toxicological effects at low concentrations such as non-cancer effects and emerging evidence that H2S is a genotoxic agent, meaning it damages DNA