Effect of ozonation on the biodegradability of atrazine in GAC columns

The biodegradation of atrazine as influenced by preozonation was studied in biological GAC columns. Metabolism of isopropyl-¹⁴C atrazine produced more ¹⁴CO₂ than ring-UL-¹⁴C atrazine, indicating dealkylation was more rapid than ring cleavage. Preozonation increased mineralization of ring-UL-¹⁴C atrazine and, consequently, enhanced the performance of the GAC columns. Sixty-two percent of the influent atrazine was converted to ¹⁴CO₂ in columns that received ozonated atrazine and ozonated surface water, while 50% of the influent atrazine was converted to ¹⁴CO₂ in columns that received untreated atrazine and ozonated surface water, and only 38% of the influent atrazine was converted to ¹⁴CO₂ in columns with untreated influent.