Alcohol testing
is done on a regular basis through the use of breathalyzers and saliva test kits with the later gaining popularity due to the inherent relationship of saliva-alcohol levels and blood-alcohol levels. The Department of Transportation has set the legal limit for drivers at 0.08 g/ml of blood alcohol with some states adopting a lower 0.05 g/ml. This is due to new studies that more than 0.05 concentration of blood alcohol, many individuals are already considered to be impaired resulting in slow reaction times, blurred vision and even having them pass-out on the wheel. Let us discuss further the two types of tests along with their variants to show their differences along with the advantages and disadvantage of each type.Breathalyzers
are a common tool used by law enforcement in road accident analysis. This is due to the reason that most road accidents are caused by DUI driving. We often read and hear about it on the news that a driver in an accident having a blood alcohol level that exceeds limits that varies from state to state. The use of breathalyzers are not restricted to the roads and are also used in relation to workplace safety and as a standard test performed in Emergency rooms for suspected alcohol related sickness.In road accidents and deaths, more than 38% of the cases were attributed to drunken driving. So law enforcement use portable devices if sobriety tests prove that an individual is suspected of DUI to determine the actual blood alcohol level against state set limits thus justifying an arrest. Alcohol intoxication is defined legally as the amount or concentration of alcohol that is present in the blood. Blood and urine sampling in the field for testing is highly impractical, laborious and dangerous. Which is amplified by the fact that blood and urine are classified as biologically hazardous materials that can cause or lead to illness. Transport of blood can also be difficult so further testing is done in the ER which has the proper equipment and qualified personnel to obtain and test the samples in their respective laboratories.The modern Breathalyzer was invented in the 1954 by a scientist working for the Indiana State Police. It works on the principle that any alcohol ingested would show up in a person’s breath due to its absorption through the mouth, throat, stomach and intestines which finally enter the bloodstream. Alcohol has a quality that is the focus of the breathalyzer for it does not get broken down as it is absorbed by the human body. Unlike drugs that are tested for their respective metabolites or residues that are a result of the human metabolism alcohol remains unchanged until it passes through the system resulting in the dreaded hangover.As blood laden with alcohol passes through the lungs, it moves across the membranes of the lung’s air sacs into the air and as we exhale is expelled out of the body. Alcohol being volatile will evaporate in a solution so an accurate estimate of blood alcohol could be obtained from analyzing the amount of alcohol present in the exhaled air. The figures used in association with blood alcohol levels indicate the amount of alcohol in grams per milliliter of air. So if a person has a 0.08 blood alcohol count that would constitute a concentration of 0.08 grams of alcohol for every 100ml of blood. The American Medical Society has determined that a person becomes impaired at blood alcohol levels of 0.05 and above and with higher concentration could kill. Breathalyzers come in 3 forms; the breathalyzer which works with a test membrane the exhaled breath passes through that changes color if alcohol is present. The next type, Intoxilyzers detects alcohol through infrared spectroscopy. And lastly, Alcusensor III or IV, that detects a chemical reaction of alcohol in an internal fuel cell.Regardless of the type it employs the use of a mouthpiece through which exhaled air passes through and travels into a system of photocells connected to a meter that measures color change in two glass vials that contain the chemical reaction mixture. If alcohol is present the photocell produces current that is interpreted by a meter attached to them which is how the common breathalyzer works. The Intoxilyzer has the air passing through a test chamber where an infrared beam passes through and exits a lens into a filter to a photocell and processor that digitally interprets the resulting Infrared light absorption reaction. The last type Alcosensor III and IV uses two platinum electrodes in a fuel cell which are sandwiched by porous acid-electrolyte materials. These materials produce a current when alcohol in exhaled breath passes through them allowing detection and interpretation by a meter.

Saliva Alcohol Testing
This newer approach to detect the levels of blood alcohol concentration is fast gaining popularity due to the simplicity and increased accuracy. Due to a relationship of 1:1 for blood and saliva alcohol, while with breath levels are at 00048:1 making saliva a more sensitive testing medium. Some types employ simple strips of paper that is dipped into the sample saliva and colored bands indicate the presence and concentration. Newer types have included in their kits, swabs of highly absorbent materials that is swabbed or wiped across the gums, tongue and cheeks until the material is wet. It is then pressed onto a test kit with a window through which the saliva is absorbed and travels through capillary action into the test material that contains alcohol reactive materials that give a quantitative number with respect to blood alcohol limits.

As shown through the above discussion on the different types and methods of measuring blood alcohol levels they both prove to be effective and are currently used worldwide. Both work differently but serve the same purpose which is to identify possible DUI caused accidents or whenever possible as preventive measures to remove drunk drivers off the streets making them safer for other motorists and pedestrians alike. At home, saliva kits can be used to help parents in the detection of alcoholism in children which has grown to alarming levels with children beginning at the age of 12 or even younger.