Chlorine, which was used as a poisonous gas in World War I.
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There are several but one that comes to mind is Chlorine gas.
Mercury. Mercury is a toxic element that can be harmful when inhaled as a vapor. It is commonly stored in containers to prevent accidental exposure.
Silicon is the second most abundant element in Earth's crust and is not considered toxic to humans. While silicon itself is not poisonous, certain compounds containing silicon, such as silicates, may cause irritation or other health issues if inhaled or ingested in large amounts.
Liquid nitrogen is not poisonous, however, it can be dangerous if it comes into contact with skin or if it is inhaled because of its extremely low temperatures. It can cause severe burns or frostbite upon contact with skin and can displace oxygen in the air if inhaled in high concentrations.
g o o g l e it
The synonym for poisonous is toxic.
All Out is a specific type of mosquito repellent that works in a vaporizer. It is poisonous to the insects, but can be safely inhaled by humans.
Mercury is an element and is very poisonous. It is not used as a drug.
There are several poisonous elements, but one of the most well-known is arsenic. Arsenic is a naturally occurring element that can be toxic in various forms and concentrations. It is known to cause serious health issues when ingested or inhaled.
Carbon monoxide (CO) is a poisonous gas that is often produced by incomplete combustion of carbon-containing materials such as gasoline, wood, and natural gas. It is colorless, odorless, and can be deadly when inhaled in high concentrations as it binds to hemoglobin in the bloodstream, reducing the ability of blood to carry oxygen.
chlorine