Fact: Totally false. We challenge you to prove otherwise. CO2 is in our every breath, in the carbonated sodas and waters that we drink and in the dry ice that helps us keep our food cold and safe. We breathe in 385 parts per million and then exhale 40,000 parts per million with no ill effects.
We breathe the 40,000 ppm into victims needing CPR and it does not cause them to die!
The monitoring systems in U.S. submarines do not provide an alert until CO2 levels reach 8,000 ppm which is higher that natural CO2 levels have been on Earth in the last 540 million years.
CO2 is a great airborne fertilizer which, as its concentrations rise, causes additional plant growth and causes plants to need less water. Without CO2 there would be no life (food) on Earth. The 100 ppm of CO2 added to the atmosphere since the start of the industrial revolution has caused an average increase in worldwide plant growth of 12 percent and of 18 percent for trees.