Driving Under the Influence of Drugs: When the Law Misses the Mark.

According to Florida law, an individual is not guilty of driving under the influence of drugs unless impairment is observed and is due to one or more controlled drugs listed in the Florida Statutes. Many prescription drugs, over-the-counter drugs and novel psychoactive compounds that can cause significant impairment are not included in this list. Five other states within the USA including Alaska, Hawaii, Massachusetts, New York and Oregon have similar or other restrictive language in their impaired driving statutes. From January of 2007 to February of 2018, 1,344 blood specimens and 1,796 urine specimens were analyzed for drugs in impaired driving cases in Palm Beach County, Florida. Over the past 11 years, 21% (212 out of 1,028) of all drug-positive blood specimens and 47% (711 out of 1,527) of all drug-positive urine specimens contained at least one non-controlled drug, often mixed with controlled drugs. Despite documentation of observed impairment with the concurrent identification of impairing drugs, an impaired driving charge could not be supported due to the phrasing of the law in Florida. If the intent of drug-impaired driving laws is to improve safety by removing impaired drivers from the road, a more all-encompassing "any impairing drug" law would be more appropriate. Linking the charge to a drug possession law framework or using other restrictive language is not the most effective means to improve road safety.

Quantitation of benzodiazepines in whole blood by electron impact-gas chromatography-mass spectrometry.

Benzodiazepines are frequently encountered in forensic toxicology. A literature search was conducted to find a simple method using electron impact-gas chromatography-mass spectrometry (EI-GC-MS) to examine whole blood specimens for the most commonly encountered benzodiazepines in the United States. A recently published method was identified in the literature search and used as a starting point for development of a new procedure to be used for routine analysis of forensic toxicology case samples. The procedure was then developed and validated as a rapid and efficient method for the screening and quantitation of benzodiazepines in blood using liquid-liquid extraction and EI-GC-MS in selective ion monitoring mode. Materials and instrumentation common to most forensic toxicology laboratories were utilized while obtaining LODs from 5 to 50 ng/mL and LOQs of 50 ng/mL or less using 1 mL of sample. Target compounds were chosen based on availability and common use in the United States and include diazepam, desalkylflurazepam, nordiazepam, midazolam, oxazepam, temazepam, lorazepam, clonazepam, and alprazolam (relative elution order). The linear range (r2 > 0.990) was validated from 50 to 1000 ng/mL for all analytes. The CV of replicate analyses at both 50 and 200 ng/mL was less than 4%. Quantitative accuracy was within +/- 16% at 50 ng/mL and within +/- 7% at 200 ng/mL. The validated method provides an efficient procedure for the quantitation of a broad range of the most common benzodiazepines in blood at meaningful limits of detection and quantitation using standard laboratory equipment and a small amount of sample.

Carfentanil in Impaired Driving Cases and the Importance of Drug Seizure Data.

Drug seizures containing carfentanil continue to increase in Palm Beach County, FL, USA despite international efforts to control the distribution of the drug. The analysis of drug seizures from the county in 2016 and 2017 demonstrated that carfentanil was the most commonly identified fentanyl analog and was most often detected in combination with heroin, fentanyl, furanyl fentanyl and/or other fentanyl analogs. Carfentanil is an ultra-potent opioid requiring a method with adequate sensitivity for detection in blood specimens from impairment cases. Previous research indicated that carfentanil could not be identified in biological specimens by routine drug testing protocols and that detection requires targeted analysis with greater sensitivity. Due to the prevalence of carfentanil in drug seizures, a sensitive targeted qualitative method by liquid chromatography tandem mass spectrometry in antemortem blood samples was evaluated, validated and implemented. The method included identification of carfentanil, acetyl fentanyl, beta-hydroxythiofentanyl, butyryl fentanyl, fentanyl, furanyl fentanyl, kavain, mitragynine, MT-45 and U-47700. In 2017 carfentanil was the second most frequently detected drug, after ethanol, in driving under the influence blood cases. Of all blood cases in which drug testing was performed (n = 145), carfentanil was detected in 38% followed by alprazolam (29%), fentanyl (27%), delta-9-tetrahydrocannabinol (24%) and morphine (23%). In toxicology cases carfentanil was rarely identified alone (only four cases) and was most commonly identified with other opioids (73% of cases), benzodiazepines (43%) and stimulants (29%). The high incidence of carfentanil-positive cases detected by this method underscores the importance of continually monitoring regional drug seizure trends, and evaluating the adequacy of toxicology testing panels based on these trends.

Long-Term Blood Alcohol Stability in Forensic Antemortem Whole Blood Samples.

The effect of long-term room temperature storage on the stability of ethanol in whole blood specimens was investigated. One hundred and seventeen preserved whole blood case samples (110 of 117 with two tubes of blood in each case) were used for this study. One tube from each case was initially tested for blood alcohol concentration (BAC) for criminal driving under the influence proceedings. Cases positive for ethanol ranged in BAC from 0.023 to 0.281 g/dL. The second tube, if present, remained sealed. All blood samples were then stored at room temperature. After 5.4-10.3 years, the opened tubes were reanalyzed for BAC by the same laboratory that performed the initial testing using the same method and same instrumentation. After the same storage period, the unopened tubes were sent to a different laboratory, using a different method and different instrumentation, and reanalyzed for BAC after a total of 5.6-10.5 years of room temperature storage. Seven samples initially negative for alcohol remained negative. All samples initially positive for ethanol demonstrated a decrease in BAC over time with a statistically significant difference in loss observed based on blood sample volume and whether or not the tube had been previously opened. The decrease in BAC ranged from 0.005 to 0.234 g/dL. Tubes that were not previously opened and were more than half full demonstrated better BAC stability with 89% of these tubes demonstrating a loss of BAC between 0.01 and 0.05 g/dL.

A study of blood alcohol stability in forensic antemortem blood samples.

The effect of long-term storage on alcohol stability in preserved forensic antemortem blood samples was investigated. Thirty-two whole blood case samples (each with two tubes of blood) were used for this study. One tube from each case was analyzed for blood alcohol concentration (BAC) for court proceedings of driving under the influence (DUI), and all blood samples were then stored under refrigeration. After the storage time (ranging from 13 to 39 months) both tubes of blood for each case were reanalyzed for BAC and the results were compared to the original analysis. Seven samples originally negative for alcohol analysis remained negative. The comparative data for 25 samples demonstrated various losses in BAC in both tubes. A significant loss with a mean of 0.015g/dL, was observed in previously opened tubes compared to a mean loss of 0.010g/dL in unopened tubes. In order to determine the effect of other storage conditions, the same blood samples were then stored at room temperature for 6 months followed by 38°C for 7 and 28 days and analyzed for BAC at the end of each storage time period. The seven alcohol negative cases remained negative when stored at room temperature or at 38°C. Six months of storage at room temperature decreased BAC further for both tubes of the alcohol positive cases with a mean loss of 0.014g/dL. Further storage at 38°C for 7 days did not cause any significant change in BAC. Storage at 38°C for 28 days caused some loss in BAC which was determined to be significant by statistical analysis.

Ethanol analysis by headspace gas chromatography with simultaneous flame-ionization and mass spectrometry detection.

Ethanol is the most frequently identified compound in forensic toxicology. Although confirmation involving mass spectrometry is desirable, relatively few methods have been published to date. A novel technique utilizing a Dean's Switch to simultaneously quantitate and confirm ethyl alcohol by flame-ionization (FID) and mass spectrometric (MS) detection after headspace sampling and gas chromatographic separation is presented. Using 100 µL of sample, the limits of detection and quantitation were 0.005 and 0.010 g/dL, respectively. The zero-order linear range (r(2) > 0.990) was determined to span the concentrations of 0.010 to 1.000 g/dL. The coefficient of variation of replicate analyses was less than 3.1%. Quantitative accuracy was within ±8%, ±6%, ±3%, and ±1.5% at concentrations of 0.010, 0.025, 0.080, and 0.300 g/dL, respectively. In addition, 1,1-difluoroethane was validated for qualitative identification by this method. The validated FID-MS method provides a procedure for the quantitation of ethyl alcohol in blood by FID with simultaneous confirmation by MS and can also be utilized as an identification method for inhalants such as 1,1-difluoroethane.

Quantitation of opioids in whole blood by electron impact-gas chromatography-mass spectrometry.

Opioids are frequently encountered in Forensic Toxicology casework. A PubMed literature search was conducted to find a method using electron impact-gas chromatography-mass spectrometry to examine whole blood specimens. A previously published method was identified, and an updated version was provided by the State of North Carolina Office of the Chief Medical Examiner. This procedure was used as a starting point for development and validation of a refined procedure to be used in the Palm Beach County Sheriff's Office Forensic Toxicology laboratory for routine analysis of antemortem forensic toxicology case samples. Materials and instrumentation common to most forensic toxicology laboratories were utilized while obtaining detection limits from 1 to 10 ng/mL and quantitation limits of 2.5 to 10 ng/mL using 1 mL of whole blood. Target compounds were chosen based on applicability to the method as well as availability and common use in the United States and include dihydrocodeine, codeine, morphine, hydrocodone, 6-monoacetylmorphine, hydromorphone, oxycodone, and oxymorphone. Each analyte demonstrated two zero-order linear ranges (r(2) > 0.990) over the concentrations evaluated (from 2.5 to 500 ng/mL). The coefficient of variation of replicate analyses was less than 12%. Quantitative accuracy was within ± 27% at 2.5 ng/mL, ± 11% at 10 ng/mL, and ± 8% at 50 ng/mL. The validated method provides a more sensitive procedure for the quantitation of common opioids in blood using standard laboratory equipment and a small amount of sample.