Unit 4: Forensic Toxicology Mr. Ross Brown Brooklyn School for Law and Technology

What are the ways alcohol affects different organ systems? 7 April 2016 Do now: How do forensic experts determine if a person has consumed alcohol?

In this unit we will learn about: How alcohol is absorbed in our bodies The effects of alcohol on our circulatory systems How breath-test instruments work How the law regards alcohol The role of the toxicologist Techniques used by toxicologists The work of drug recognition experts

What are the ways alcohol affects different organ systems? Toxicology: a branch of biology, chemistry, and medicine that studies the adverse effects of chemicals on living organisms. Forensic toxicology: applying toxicology to aid medical or legal investigation of death, poisoning, and drug use

What are the ways alcohol affects different organ systems? Approximately 40% of traffic deaths are alcohol-related – That’s over 20,000 deaths per year Reality: people drink, and people drive – How can we keep them from doing both together?

What are the ways alcohol affects different organ systems? Alcohol in our bodies – Drunk drivers are arrested after they did their drinking. How can we measure how much they’ve had? – Absorption: passage of alcohol across the wall of the stomach and small intestine and into the bloodstream

What are the ways alcohol affects different organ systems?

Remember, alcohol is a _________________ Depresses central nervous system Is absorbed by the brain – Why can we not simply measure the amount of alcohol absorbed in someone’s brain? depressant

What are the ways alcohol affects different organ systems? 8 April 2016 Do now: Why does alcohol affect men and women differently?

What are the ways alcohol affects different organ systems?

Alcohol is carried throughout our bodies in our blood – So, blood-alcohol content is a good proxy for amount of alcohol in our brains

What are the ways alcohol affects different organ systems? Our body works hard to eliminate the alcohol – Oxidation: in our livers, interacts with enzymes and is converted into CO 2 and water – Excretion: in our breath, urine, and perspiration. Research shows that the amount of alcohol in our breath is in direct proportion to the amount in our blood.

What are the ways alcohol affects different organ systems? So, in our bodies, alcohol is… – Absorbed in our bloodstream – Distributed by water in our body – And eliminated via oxidation and excretion

What are the ways alcohol affects different organ systems? Alcohol in our Circulatory System – Measured directly through a blood test or by measurement of the alcohol content of our breath

How can we test for alcohol (without being too invasive?) 11 April 2016 Do now: Why is it unappealing to use blood tests for checking if drivers have been drinking? Provide 2 good reasons.

How can we test for alcohol (without being too invasive?) Breath-test instruments – The Breathalyzer – Developed in 1954

How can we test for alcohol (without being too invasive?) From your blood to your lungs – Alveoli: small sacs in your lungs where exchange of air and blood occurs

How can we test for alcohol (without being too invasive?) Remember our discussion on field tests for drugs? – Breathalyzer contains a small amount of chemicals that reveal the presence of alcohol in your breath, and so also in your blood

How can we test for alcohol (without being too invasive?)

How harmful is alcohol to your ability to drive safely? 13 April 2016 Do now: Which is more harmful to your ability to drive safely, being drunk or using your cell phone? What else can make it difficult to drive safely?

What are other ways we can test for blood alcohol content? 14 April 2016 Do now: How can police tell when you’re drunk?

What are other ways we can test for blood alcohol content? Field Sobriety Test – Used to assess the degree of a suspect’s physical impairment and whether a further evidential test is justified.

What are other ways we can test for blood alcohol content? Field Sobriety Test – Horizontal eye nystagmus – Walk and turn – One-leg stand

What are other ways we can test for blood alcohol content? Blood analysis – More accurate – Chemical analysis performed in a lab

What are other ways we can test for blood alcohol content? Collection and preservation of blood – Always drawn under medically accepted conditions – Airtight container; refrigerated – Add anticoagulant – Add preservative

Homework #4 14 April 2016 In NYS, what blood alcohol content (BAC) serves as legal evidence that you are impaired? What BAC serves as evidence of intoxication? What BAC serves as evidence of aggravated driving while intoxicated? Full sentences!

How do our laws categorize alcohol consumption? 15 April 2016 Do now: Based on our homework, what distinctions does the law make about the amount of alcohol someone consumes?

How do our laws categorize alcohol consumption?

Levels set by individual states Influenced by the National Safety Council and American Medical Association Originally 0.15%

How do our laws categorize alcohol consumption? ALCOHOL, OTHER DRUGS AND THE LAW In New York State, you can be arrested for any of these offenses: – Blood alcohol content (BAC) is the percentage of alcohol in your blood and is normally determined by a chemical test of breath, blood, urine or saliva. A BAC of more than.05 percent is legal evidence that you are impaired, a BAC of.08 percent or higher is evidence of intoxication, and a BAC of.18 percent or more is evidence of aggravated driving while intoxicated.

How do our laws categorize alcohol consumption?