A Seattle jury awarded $275 million on Thursday to six adults and seven children who alleged they suffered brain damage after being exposed to PCB, or polychlorinated biphenyls, at a school in the state of Washington.

The two-month trial is the fifth in Seattle’s King County Superior Court against Bayer’s Monsanto over exposure to PCB at the school, called Sky Valley Education Center. In the past year, juries have awarded $269 million in verdicts in three trials, but a fourth ended on July 14 in a mistrial after jurors deadlocked.