Determination of glycyrrhetic acid after consumption of liquorice and application to a fatality

Abstract

Besides alcohol and drugs of abuse, several popular foods contain potentially toxic substances and cases of intoxication after consumption of these foods attract notice of forensic toxicology. This is also true for the case of a 34-year-old woman who was suspected to have suffered lethal acute intoxication from eating nothing but liquorice over a period of several months. The liquorice ingredient glycyrrhizin and its metabolite glycyrrhetic acid, which elicits a mineralocorticoid effect, were determined in the sort of liquorice the woman had consumed by using LC-MS/MS. In addition, a fast and sensitive procedure for the quantification of glycyrrhetic acid including a simple sample preparation was developed. The method was proven to be accurate and precise. In a liquorice ingestion experiment, 200 g of liquorice had to be eaten. Afterwards, concentrations of glycyrrhetic acid in the blood of up to 434 ng/ml were measured. Since only traces of glycyrrhetic acid had been found in the blood and stomach content of the deceased woman, the possibility of acute lethal glycyrrhetic acid intoxication could be eliminated. Excluding other causes of death, the woman is believed to have died from a lethal hyperglycemic coma. Nonetheless, the influence of harmful and toxic substances in food should be taken into consideration in special cases.