This module introduces the fundamental, theoretical and practical concepts of forensic chemistry. It will explain some of the key concepts relating to the classification of drugs, toxicological investigations, trace and contact evidence, body fluid analyses, and the use of modern analytical instruments in forensic chemistry.

a) describe differences between classes of drugs of abuse and be able to outline methods for their identification, including sampling techniques and presumptive tests;

b) describe what is meant by toxicology and recognise the factors that affect the toxic dose of a substance;

c) be aware of trace and contact evidence and state methods used to characterise glass, fibres, paint and hair;

d) describe how to test blood and body fluids and how to select biological samples as evidence;

e) describe modern analytical instrumentation and identify advantages and disadvantages of each;

f) understand how the laws of chemistry can be applied to forensic science and discuss how chemical properties of compounds can be used to collect evidence;

g) distinguish between the major classes of drugs and illustrate how to sample and quantify such samples;

h) discuss the problems of detection and diagnosis of poisons and appreciate how to manipulate data to provide accurate quantitative results;

i) explain how analysis of glass, fibres, paint and hair can be achieved, will be able to justify the method of analysis selected, and explain the scientific principles behind each technique;

j) discuss tests for blood, semen and saliva and contrast the techniques used with those for DNA analysis;

k) select the correct technique according to the nature of the investigation;

l) explain and evaluate the use of instrumental techniques in analysis.

16 x 1h lectures, 5 x 3h workshops

On completion of the module a student will be able to:

a) analyse and identify simple drugs by thin-layer chromatography;

b) relate experimental practice in the laboratory to those at crime scenes;

c) recognise patterns of poisoning and evaluate analytical approaches used in forensic toxicology, with critical assessment of accuracy and suitability for purpose;

d)  differentiate between physical and chemical concepts that underpin analysis of glass, fibres, paint and hair, and recognise the significance of contamination and reliability of trace evidence;

e) appraise the validity of information from biological sources and assess critically forensic data, thus extending their understanding of the significance of principles of chemistry and science in general.

 f) use a scientific approach to investigate practical problems with an analytical aspect.

A written exam (1 h) will test the student's knowledge and understanding as elaborated under the learning outcomes. The coursework (workshops) will allow the student to demonstrate his/her ability to judge and critically review relevant information.

An introduction to forensic science and how chemistry is key to the success of this field. Brief introduction to drugs – cannabis, heroin, cocaine, amphetamines, LSD and barbiturates.

Identification of the drugs of abuse: schemes for identification of trace and bulk samples. Sampling techniques, presumptive tests, thin layer chromatography and instrumental techniques (GC, IR, GC-MS, GC-IR). Drug quantification.

Introduction to  toxicology. Factors affecting toxic dose – carcinogenic and mutagenic substances, age and size, state of health, history of exposure, paradoxical reactions. Chemistry of poisoning; mode of action of poisons, ingestion, metabolism and excretion. Schemes for identification.

Contact and trace evidence. Amounts of material transferred and persistence of material. Recovery of trace materials. Characterisation and comparison of glass, fibres, paint and hair.

Analysis of body fluids. Description of blood and its components. Composition and analyses/tests. Semen; saliva.

Modern analytical instrumentation. GC/HPLC, MS, GC-MS, FTIR. Description of each technique and the merits and disadvantages of each.

A up-to-date indicative reading list will be included in the Course Handbook.