Alcohol Testing Evolves
Originally alcohol testing was performed by collecting blood samples. But the science of alcohol tests has evolved and it was soon discovered that the amount of alcohol that is in the blood could be determined by examining urine, saliva, and the deep breath of the lungs.
Unlike food, once ingested, alcohol gets absorbed straight in the bloodstream without being digested. The blood carries the molecules of alcohol further on to the liver, lungs, heart, and to the brain. Eventually more than 85% of the alcohol gets eliminated through the process of metabolism in which liver plays an important role.
Another part is evaporated into the breath and then exhaled out by breathing. A small part is eliminated through urine and saliva. This means that alcohol level can be tested by collecting breath, blood, urine or saliva samples, although some of these testing methods are more reliable than others.