Ten adults and one minor are hospitalized after eating wild mushrooms they foraged outside of Yellowstone National Park in Montana. According to the nonprofit educational group, Northwest Mushroomers Association, there are about 7,400 poisonings from ingesting poisonous mushrooms each year in the U.S. and about three deaths. In March, for example, 40 people fell ill, and another four died during a mushroom poisoning outbreak in California. When foraging for mushrooms, Cripps says to avoid using a plastic bag and instead opt for a basket or paper bag. And the toxins found in poisonous mushrooms are some of the deadliest natural poisons on earth.