TOXICOLOGY PART II

Alcohol

PA DUI Regulations

DUI - Driving Under the Influence (DWI, OUI, OMVI, DWAI, DWUI, DUIL, DUBAL)

Penalties Jail time License suspension Fines

Legal Limits 21 and over – 0.08% Under 21 – “Zero Tolerance” - 0.00 -0.02% Commercial vehicle operators – 0.04%

** Over 56,000 arrests for DUI in PA last year**About 12,000 crashes and 400 fatalities

The Path Alcohol Follows through the Body

1. Alcohol (ethanol) is ingested through the mouth.

2. Some alcohol passes into the bloodstream through the stomach.

3. Most alcohol passes into the bloodstream through the small intestine.

4. The heart pumps blood containing alcohol to the brain and other organs.

5. Alcohol travels to the liver where it is metabolized

Broken down

Metabolism of Alcohol by the Liver

The liver is an organ of the digestive system. It plays an important role in detoxifying the blood.

10% of ingested alcohol remains unchanged and leaves the body via breath, sweat and urine.

90% of all alcohol ingested is broken down in the liver.

CO2 + H2OCarbon Dioxide Water

OH (hydroxyl) is the group that is common to all alcohols

Metabolism of Alcohol

The body starts to detoxify alcohol upon ingestion

The average rate of removal is about 0.015 percent per hour

If the same number of drinks is consumed over a longer period of time then the BAC would be lower

1 drink2 drinks3 drinks4 drinks

Marked Impairment

Rapid Consumption of Alcohol

One drink" is a 1 1/4-ounce shot of 80-proof liquor (even if it's mixed with non-alcoholic drinks), a 4-ounce glass of wine, or 10 ounces of 5.7% beer.

Factors that Affect Blood Alcohol Levels

Weight Gender Amount of food in stomach Amount of alcohol consumed Period of time over which alcohol is ingested

Calculating Blood Alcohol Levels

BAC – Blood Alcohol Content Varies in gender due to differing amounts of water

weight

BAC Calculation Example

A 220lb. Man drinks 2 shots (1.5 oz. each) of 90 proof whiskey. Calculate his BAC.

What is proof?

0.04%

BAC Levels and Impairment

0.10

0.09

0.08

0.07

0.06

0.05

0.04

0.03

0.02

0.01

Ethanol is a central nervous system depressant

Decline in visual function, Decline in ability to perform 2 tasks at the same time

Impaired steering and tracking ability, Reduced Coordination,Reduced ability to respond to emergency driving situations

Inability to concentrate, Loss of short-term memory, Loss of speed control, Impaired perception, Reduced information processing capability.

Reduced ability to maintain lane position and brake appropriately

Relative Crash Risk and BAC Level

Based on this data.. There is a direct relationship between BAC and crash risk Crash risk greatly increases at 0.05% BAC and above Nationally, there has been interest in lowering the legal limit for

individuals age 21 and over to 0.05%

Methods of Alcohol Detection in Breath

3Types: Breathalyzer – Colorimetry/Spectrophotometry

Reduction of dichromate to chromium producing a color change from orange to green

Intoxilyzer – Infrared spectroscopy Absorption of infrared waves by alcohol

Alcosensor – Fuel cell technology Reduction of alcohol to acetic acid by a platinum

catalyst. This produces a measureable electrical current.

The Breathalyzer Reaction

In the field, this semi-quantitative test can be easily used.

When breath containing alcohol is exhaled into the blue end of the device, it reacts with the dichromate. More green means a higher BAC.

Spectrophotometry

Spectrophotometry is a method used to measure the amount of a chemical substance by measuring the intensity of light that passes through a sample solution.

Components of a Spectrophotometer

Color and Spectrophotometry

Objects absorb only certain wavelengths of light. Those that are not absorbed are transmitted or reflected. The transmitted or reflected wavelengths are those that we see.

100% Transmittance0% Absorbance

0% Transmittance100% Absorbance

Creating a Standard Curve for Ethanol

Several standard solutions containing a known concentration are reacted with the dichromate reagent.

Samples are placed in the spectrophotometer and their % absorbance is measured. (one of the standards always contains 0% ethanol)

A graph is created by plotting % absorbance on the y-axis and ethanol concentration on the x-axis.

Determining the Concentration of Ethanol in an Unknown Sample

After creating a standard curve, measure the absorbance of the unknown sample and compare to the curve.

An absorbance of 0.5 = 0.55% Ethanol

Some Popular Breathalyzer Myths

Myth: Chewing on coffee grounds, eating onions, using breath mints will help you pass a breathalyzer test

Fact: Good or Bad breath does not have any impact on the test

Myth: Placing pennies or batteries in your mouth before being tested

Fact: No effect on the test

Myth: Hyperventilating before being tested

Fact: Actually increases your BAC by as much as 20%

Lit, but not the Brightest Bulb

To beat a possible DUI, this man ripped apart his underwear in the back of a police car and began to eat them thinking that the cotton would absorb the alcohol.

He was latter acquitted in court because his BAC was not over the legal limit.

People had to be removed from the court room because they had difficulty trying to contain their laughter