Kerala temples have enforced a blanket ban on using Nerium oleander in daily rituals. Why?

Experts said different oleander species contain highly poisonous chemical substances that can directly affect the heart. A 24-year-old woman died due to accidental oleander poisoning in Kerala's southern district of Alappuzha two weeks ago, triggering outrage and resulting in the ban on the flower from ritualistic use at scores of temples in the state.