An officer who witnessed the incident, said it seemed to happen “all at once.”
“It seemed like it happened over the course of just a few minutes,” he said. “Suddenly we had several people down on the ground experiencing some type of cardiac arrest or medical episode and so we immediately started doing CPR and moving people.”. https://www.click2houston.com/news/local/2021/11/06/hfd-responding-to-reports-of-multiple-injuries-at-astroworld-festival/
A tinfoil helmet?
That's what the graphene oxide crossing into the brain is for.