Is PBO Toxic to Fish and Other Aquatic Organisms?

Based on laboratory studies:

  • PBO is moderately toxic to estaurine fish (LC50 = 3.94 ppm) and freshwater fish (LC50 = 1.9 ppm) on an acute (short term) exposure basis.
  • A No Observed Effect Concentration (NOEC) of 0.04 ppm was estimated from a chronic early life stage of fish study with fathead minnow in which embryo survival at hatch and length and weight of larvae was observed at the Lowest Observed Effect Concentration (LOEC) of 0.11 ppm.
  • PBO ranges from moderately toxic (LC50 = 12.0 ppm) to highly toxic (LC50 = 0.51 ppm) to freshwater invertebrates and highly toxic to estaurine/marine invertebrates on an acute basis.
  • A NOEC of 0.030 ppm was estimated from a chronic life cycle study where Daphnia magna exhibited reproduction affects at the lowest observed effect concentration (LOEC) of 0.047 ppm.