Interpretation of Blood Concentrations: The presence of cocaine at a given blood concentration cannot usually be associated with a degree of impairment or a specific effect for a given individual without additional information. This is due to many factors, including individual levels of tolerance to the drug and artifactual changes in cocaine concentrations on storage. There is a large overlap between therapeutic, toxic and lethal cocaine concentrations and adverse reactions have been reported after prolonged use even with no measurable parent drug in the blood. Typical concentrations in abuse range from 0-1mg/L, however, concentrations up to 5mg/L and higher are survivable in tolerant individuals. After single doses of cocaine, plasma concentration typically average 0.2-0.4 mg/L. Repeated doses of cocaine may result in concentrations greater than 0.75 mg/L.

Following intranasal administration of 106 mg, peak plasma concentrations of cocaine averaged 0.22 mg/L at 30 minutes, while benzoylecgonine concentrations averaged 0.61 mg/L at 3 hours. Oral administration of 140 mg/70 kg cocaine resulted in peak plasma concentrations averaging 0.21 mg/L of cocaine at 1 hour. Single 32 mg intravenous doses of cocaine produced an average peak plasma concentration of 0.31 mg/L of cocaine within 5 minutes. Smoking 50 mg of cocaine base resulted in peak plasma cocaine concentrations averaging 0.23 mg/L at ~ 45 minutes and 0.15 mg/L of benzoylecgonine at 1.5 hours.

First, my condolences on the death of your son.

If your son died immeditely, then a blood cocaine concentration of .02mg/L is not considered high, but as also pointed out by LabRat, cocaine is rapidly metabolized which means his blood level could have been higher prior to the crash. I agree. However, if he passed after several hours of medical treatment, his cocaine concentration may have been much higher at the time of the crash.

Despite many laws against drug use and driving and public awareness campaigns about not using drugs and driving, there is very little scientific data that acute cocaine impairs driving (to the degree that alcohol or other drugs may). In fact, the National Highway Traffic Safety Administration, in a relatively recent review on Drugs and Driving, concluded that stimulants are not clearly causal factors in impaired driving and that some stimulants may actually improve driving. However, those studies are with relatively low doses of stimulants and do not consider crashes, withdrawal or higher doses all of which have psychological and physiological effects that would impairs skills necessary for safe motor vehicle operation. There are so many factors to consider in determining causality, it would be impossible to say without much more data.

So, yes, your son was under the influence of cocaine but without a great deal more information, it would be speculative to conclude that his cocaine use was a significant factor in his fatal crash. I hope that helps to answer your question.