Do some research on your own using Google.
Note that dozens of people died of Iodine poisoning in Russia after the recent false alarm nuclear reactor incident.
Note that at least one family died in Israel by duct-taping and plastic sheeting their home in a test for prevention in a chemical attack. The house was so air-tight that they suffocated from lack of oxygen.
I knew about Russia, but had no idea about the family in Israel. That information alone is important!