Molasses discharged by an alcohol fermentation plant into the Pampanga River on Sept. 19 may have reduced the amount of dissolved oxygen to a degree that could have triggered a fish kill incident near the towns of Macabebe and Masantol. At a hearing of the provincial board’s environment committee on Thursday, the Environmental Management Bureau (EMB) said the biochemical oxygen demand (BOD) after molasses spilled into the river was measured at 23,574 milligram per liter, which was far higher than the 50 mg/L allowed by law for water for swimming. Molasses needs to be broken down by bacteria in the water and the volume of the pollutant increases the amount of oxygen which the bacteria consumes as measured by the BOD.

Orejas, T. (2017, October 1). Alcohol eyed in Pampanga River fish kill. Philippine Daily Inquirer, p. A10.