Forensic Toxicology - Guest 2

Question 1

What are the legal limits of alcohol in blood and breath? And in which law is it described?

Answer 1

Article 8 Dutch Road Traffic Act

blood 0.5 mg/ml
breath 220 microgram/l

Question 2

What are 3 steps in the driving under influence procedure?

Answer 2

1 Driver is stopped because of behaviour, control or accident
2 pre-selection test
3 Evidence test

Question 3

What are pre-selection tests? (3)

Answer 3

1 alcohol breath test
2 oral fluid test for drugs
3 observations/sobriety test

Question 4

What are 2 evidence tests?

Answer 4

1 evidential breath analysis –> confirmation of alcohol
2 blood analysis –> alcohol and/or drugs

Question 5

What are pre-selection tests for ETHANOL? (3)

Answer 5

1 Electrochemical cell
2 Oxidation of ethanol
(anode)
3 Reduction of oxygen
(cathode)

Question 6

What are 2 evidential breath test instruments? And what is done if they give invalid results?

Answer 6

1. Electrochemical cell
2. Infrared (IR) sensor

• invalid result = blood sampling

Question 7

What are the 3 advantages of oral fluid as matrix for drugscreening?

Answer 7

1 easy to collect compared to blood
or urine

2 window of detection

3 high concentrations of
drugs compared to blood

Question 8

What are the 3 disadvantages of oral fluid as matrix for drugscreening?

Answer 8

1 difficult to collect after drug use

2 contamination due to smoking, snorting
or oral routes of administration

3 No reliable estimation of the blood
concentration from oral fluid

Question 9

What is in a sample set for collecting blood? (5)

Answer 9

• 2 tubes of 5 ml, with preservative and anticoagulant
• desinfectant (no alcohol!)
• form for a request for toxicological examination
• labels with a unique identification number
• labels to seal the box