If a large amount of helium gas is inhaled, the oxygen in the body will be replaced by helium gas, resulting in hypoxia (respiratory reflex is driven by excessive carbon dioxide in the body, but it is not sensitive to hypoxia), and even serious death.
In addition, if helium is directly inhaled from a high-pressure gas cylinder, its high flow rate will seriously damage lung tissue. A large amount of high pressure helium and oxygen can cause high pressure stress symptoms (HPNS), but a small amount of nitrogen can deal with this problem. Inhalation of helium for a long time can lead to brain damage and even death.
Most French fries bags also contain a small amount of helium, but don't worry, there is no harm. ?
Extended data:
Helium, English name helium, symbol He, colorless, odorless and nonflammable. The content of helium in the air is about 5.2 parts per million. Chemically inactive, usually not combined with other elements or compounds. 1July 908 10, Dutch physicist anis liquefied helium for the first time.
References:
Baidu encyclopedia-helium