What you'll study: Toxicology

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Our MSc Analytical and Forensic Science students study analytical toxicology as a key component of the MSc course. Toxicology is the study of drugs and poisons and at USW we focus on the analytical techniques behind such analysis.

The students receive intensive practical training in a variety of laboratory techniques which will enable them to gain employment in a toxicology lab upon graduation. Indeed, several of our recent graduates are now working as forensic toxicologists currently.

During the analytical toxicology module the students will be trained in a range of specialist techniques, from analysing heavy metal pollution in soil, to poisons in saliva samples. There is a particular focus on the analysis of illegal drugs of abuse in biological samples.

Firstly the students will examine the route by which drugs enter our body and how they interact and affect us. The analysis of hair samples for drugs is a fantastic technique which is growing in popularity across the world. The technique is very useful for forensic scientists as it allows the determination of a historical record of drug abuse or abstinence to be demonstrated. Whenever people take drugs, be it cocaine, or something as trivial as a painkiller; or we smoke a cigarette or drink a beer, compounds can enter our bloodstream and circulate around our body. 

Every hair on the body has its own blood supply and as such certain compounds in our blood (alcohol, nicotine or illegal drugs for example) can enter our hair where they become bound and remain stable for long periods. Drugs or alcohol metabolites in hair can remain bound to the hair for several months.  Alcohol itself (ethanol) does not enter the hair, but rather a metabolite of alcohol, Ethyl Glucuronide (EtG) does.

Once a drug or alcohol metabolite such as EtG has entered our hair, our students begin the task of extracting it, and then analysing the sample. Drug analysis from hair samples is a complicated and time consuming process. Our students receive detailed training in all aspects of the procedure. Our students will collect hair samples from volunteers and prepare them by careful washing and sectioning.

To get the drugs out of the hair itself samples are treated with either acids, alkali or enzymes, sometimes even water, with the aim of leaching the internal drugs out of the hair and into solution. Once extracted the sample requires further clean-up before analysis. This is accomplished in a variety of ways. Students will conduct solid phase extraction or liquid-liquid extraction on the samples to prepare them for analysis via GCMS. GCMS stands for gas chromatography-mass spectrometry. It is an instrument widely used by forensic scientists and toxicologists to analyse drugs and poisons. It is also very commonly used in the chemistry and pharmaceutical industry.

Once hair samples have been prepared for analysis they are injected onto a GCMS system for analysis. A very hot injection port often above 250°C vaporises the sample, the sample is then pushed via a carrier gas (helium usually) around a capillary column. The column is often 30 minutes in length, but tightly wound into a small circle. The purpose of the column is to separate individual components in a complicated mixture so that they exit the column one by one. As compounds exit the column after separation they enter a mass spectrometer. The mass spectrometer is a detection device capable of detecting absolutely minute traces of organic compounds. The GCMS will produce chromatography and our students will be able to quantify the results and produce toxicology reports detailing their results. 

Our students receive specialist training in the operation and maintenance of such equipment and we also place a lot of importance on their ability to develop their own methodology for the analysis. Students will research the techniques involved, and along with supervision and training from our lecturers the students will identify strategies to detect drugs and alcohol in biological samples and see the project through to completion. These are vital skills which really make our students stand out when it comes to employment opportunities.