On Wednesday, February 28, 2007, at around 12:30 pm, Boston Police responded to Excel High School in South Boston to investigate a potential hazardous incident.The caller reported a white substance in a water cooler. Two employees reported drinking the water from the cooler and the experiencing a strange taste in their mouths. Boston Public School Police secured the area after becoming aware of the incident and notified 911 for assistance. On arrival, officers met with members of the Boston Fire Department (BFD) and were brought to the location of the water cooler. Officers on the scene observed a white, crystal-like material at the bottom of the water cooler. Boston EMS transported both employees who drank the water to BMC for evaluation. BFD Hazmat Technicians secured the substance for transportation. Further investigation with the assistance of the Massachusetts State Lab confirmed that the substance was magnesium sulfate, commonly known as Epsom salts. The two employees who had ingested the substance were notified of the test results. The incident remains under investigation.