Concentrations of cocaine and benzoylecgonine in femoral blood from cocaine-related deaths compared with venous blood from impaired drivers.

The concentrations of cocaine and its major metabolite benzoylecgonine (BZE) were determined in femoral blood from 132 cocaine-related deaths and compared with venous blood from 988 apprehended drivers. Cocaine and BZE were determined by solid-phase extraction and isotope dilution gas chromatography-mass spectrometry with limits of quantitation of 0.02 mg/L for both substances. Significantly more men (95-98%) than women (2-5%) abused cocaine, although their mean age was about the same (29-30 years). Mean age (±SD) of cocaine-related deaths was 29 ± 7 years, which was not significantly different from 30 ± 8 years in traffic cases (P > 0.05). The median concentration of cocaine in blood in 61 fatalities was 0.10 mg/L compared with 0.06 mg/L in traffic cases (P < 0.001). In drug intoxication deaths, the median concentration of cocaine was 0.13 mg/L (N = 25), which was not significantly different from 0.09 mg/L (N = 36) in other causes of death. Cocaine-related deaths mostly involved mixed drug intoxications including co-ingestion of heroin, cannabis, amphetamines as well as legal drugs, such as benzodiazepines and/or ethanol. The concentrations of cocaine in blood from living and deceased persons overlapped, which makes it infeasible to predict toxicity from the analytical toxicology results alone.