A fire at a chemical plant in Rockdale County sent a colossal plume of smoke into the sky. Chemicals released from the fire at the BioLab in Conyers include chlorine, chloramine and chlorine compounds, according to the Georgia Emergency Management and Homeland Security Agency. Additionally, bromine — another chemical used in spa and pool treatments as an alternative to chlorine and has a bleach-like odor — was also detected, though at lower levels.

Love Family Professor Nga Lee (Sally) in the School of Earth and Atmospheric Sciences says "a system known as the Atmospheric Science and Chemistry Measurement Network detected a 1,400-times increase in the amount of chlorine-containing particles in the air, and a 170-times increase in the amount of bromine-containing particles in the air over Decatur on Monday morning. Typically, there is little of either element in the air."