Carbon monoxide poisoning occurs when even a small amount of the gas is breathed in. When you breathe in carbon monoxide, it finds its way into your blood stream and stops your red blood cells from carrying oxygen. Without oxygen, your body tissue and cells can start to die. Lower levels that do not kill can still cause severe harm to your health when breathed in over a long period of time. Long term effects of carbon monoxide poisoning can include paralysis and even brain damage. These long term effects can occur when people are not aware of unsafe gas appliances and the consequence of deadly gas leaks.