The aim of toxicology is to detect those substances which, at specific dosages, can be toxic for the body. “The dose creates the venom,” as Paracelsus was already putting it in the 15th century. Any substance is thus potentially toxic, and human beings are confronted every day with a large number of substances which can be harmful to them.

Medical toxicology differs from forensic toxicology (from the Latin, forum, the place where justice was served in Ancient Rome) in that the respective analysis is requested by different types of institutions – medical ones for the former, and legal ones for the latter. Using the same analytic techniques, analysts can respond to different types of requests.

In the case of medical toxicology, the request usually comes from a doctor. He/she requires a rapid response, in order to confirm or reject a diagnosis or treatment as quickly as possible. The laboratory’s answers to the questions, which are usually confined to one or more specific parameters, provide the doctor with confirmation regarding the therapeutic decision he/she has made. They may also lead him/her to modify this initial decision.

In the case of forensic toxicology, the request may come from a magistrate, an administrative authority, or even from a private individual. Their questions must be assessed by the toxicologist, who will then carry out the necessary investigations. Whereas in medical toxicology samples are taken from a living patient, in the case of forensic toxicology the human or animal source of a sample may or may not still be living. Liquids, powders, cups, glasses, food and drink are also examples of samples that may be sent to the laboratory for analysis.

Medical and forensic toxicological activities form part of the Clinical Chemistry and Toxicology Department of the Central Institute of hospitals.