RESUMEN
The presence and use of carbamate and organophosphate pesticides with agricultural and urban purposes in Colombia has been justified for pest control. However, these substances pose a national problem because of their toxic nature, which is associated with accidental poisoning or even with homicides or suicides related to acute fatal poisoning. This study aims to develop and to validate an analytical methodology for the determination of the aldicarb, carbofuran and methamidophos pesticides in blood through liquid chromatography--tandem mass spectrometry (LC-MS-MS). To this end, the method for extracting pesticides from the blood was developed, the conditions of LC were defined, the instrumental system MS-MS was optimized and the bioanalytical methodology was validated. This methodology proved to be selective, precise, accurate and linear in the concentration range from 0.10 to 5.0 µg/mL, with a limit of detection of 0.020 µg/mL for aldicarb and carbofuran and 0.050 µg/mL for methamidophos, recovery between 90% and 102%, and stability at room temperature and in the autosampler between 80% and 120%. The analytical methodology was applied to 34 forensic cases. Carbofuran was found at a concentration ranging from 0.020 to >5.0 µg/mL, aldicarb was found at a concentration ranging from 0.10 to 2.5 µg/mL and methamidophos was found at a concentration >5.0 µg/mL. In 62% of the cases, the pesticides under study were used to commit suicide. Necropsy findings of pesticide poisoning are non-specific. Therefore, toxicological blood analysis provides significant information at the forensic level, and the analytical method validated represents a sensitive, fast and reliable analysis with little solvent consumption of a small sample amount, so it is suitable for routine application in fatal pesticide poisonings.
Asunto(s)
Carbofurano , Suicidio , Aldicarb , Cromatografía Liquida , Humanos , Compuestos Organotiofosforados , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en TándemRESUMEN
Verapamil is a synthetic derivative of papaverine, which is used therapeutically as a hypertensive, antiarrhythmic and antianginal. This study describes an analytical method for the determination of verapamil in biological matrices of blood and urine, which consists of a liquid-liquid extraction of samples for analysis using liquid chromatography-mass spectrometry (LC-ESI-MS/ MS), with flurazepam as an internal standard. The method was applied to the acute fatal intoxication of a 17-year-old young woman who consumed 170 tablets of verapamil; the concentration of this medication found in the blood was 18.261mg/L and 0.369mg/L in the urine. This study also puts forth the use of LC-ESI-MS/MS in the analysis of verapamil in biological samples for applications in forensic toxicology.
El verapamilo es un derivado sintético de la papaverina que se emplea a nivel terapéutico como antihipertensivo, antiarrítmico y antianginoso. El presente estudio describe un método analítico para la determinación de verapamilo en las matrices biológicas sangre y orina, que consiste en una extracción líquido-líquido de las muestras, para luego ser analizadas por cromatografía líquida con ionización electro-spray y espectrometría de masas tándem (LC-ESI-MS/MS), empleando el flurazepam como estándar interno. El método desarrollado fue aplicado a la intoxicación aguda fatal de una joven de 17 años de edad quien consumió 170 tabletas de verapamilo; la concentración de este medicamento encontrada en sangre fue de 18.261mg/L y de 0.369mg/L en la orina. De igual forma, este estudio expone la utilidad de emplear LC-ESI-MS/ MS en el análisis de verapamilo en muestras biológicas para su aplicación en toxicología forense.