Robin Whelpton - Fundamentals of Analytical Toxicology

Information recorded on the sample container at the time the sample is collected should include the name of the patient (first and family or last name) and date of birth, patient/subject/animal number, the date and time of collection, and the sample type. Many laboratories will have a bespoke analysis request form to accompany the sample(s) on which this and any other appropriate information such as a note of any preservative added to the sample, site of collection of blood, etc. should be recorded ( Box 2.2). The date and time of receipt of all specimens by the laboratory should be recorded and a unique identifying number assigned in each case.

Table 2.5 Sample requirements: post-mortem biochemistry and toxicology

aSmaller volumes may often be acceptable, for example in the case of young children

bIncludes vomit, gastric lavage (SWO, first sample), etc.

cAlternative if vitreous humour not available

dBecause there is little information on drug distribution within solid tissues in man, collection of approximately 10 g specimens from several sites from organs such as the brain is recommended if the whole organ is available

eTablet bottles, drink containers, aerosol canisters, etc. should be packed entirely separately from biological samples, especially if poisoning with volatiles is a possibility

Table 2.6 Advantages and disadvantages of different sample types in analytical toxicology

Name, sex, date of birth, date and time of death if appropriate, details of the sample(s) sent for analysis

Name, address, and telephone number of clinician/pathologist and/or coroner's/police officer requesting the analysis, and address to which the report and invoice are to be sent. A post-mortem (reference) number may also be appropriate

Circumstances of incident (including copy of sudden death report if available)

Past medical history, including current or recent prescription medication, and details of whether the patient suffered from any serious potentially infectious disease such as hepatitis, tuberculosis, or HIV

Information on the likely cause, and estimated time, of ingestion/death and the nature and quantity of any substance(s) implicated

If the patient has been treated in hospital, a summary of the relevant hospital notes should be supplied to include details of emergency treatment and drugs given, including drugs given incidentally during investigative procedures

Note of occupation/hobbies

A copy of any preliminary pathology report, if available

In general biological specimens should ideally be stored at 2–8 °C before transport to the laboratory. Exceptions to this include hair, nail, and filter-paper adsorbed DBS. Dried blood stains and other dried forensic specimens may of course be handled similarly (Schütz et al ., 2002).

Each specimen bottle should be securely sealed to prevent leakage, and individually packaged in separate plastic bags. Particular attention should be paid to the packaging of samples to be transported by either post, or courier in order to comply with current health and safety regulations. Sample volumes or amounts smaller than those indicated in Tables 2.4and 2.5are often sufficient to complete the analyses required. Submission of very small samples may, however, result in reduced sensitivity and scope of the analyses undertaken, but nevertheless such samples should always be forwarded to the laboratory. Any residual specimen should be kept at –20 °C or below until investigation of the incident has been concluded.