Interference of the novel designer benzodiazepine 4'-chloro deschloroalprazolam with alprazolam analysis in toxicology and seized drug DUID casework.

In recent years, the emergence of the novel designer benzodiazepine 4'-chloro deschloroalprazolam has presented a new challenge for forensic laboratories by interfering with the identification and quantitation of alprazolam. As an isomer of alprazolam, 4'-chloro deschloroalprazolam has similar physicochemical properties and can be misidentified in casework samples as alprazolam without a specific method to differentiate the two analytes. Starting in late 2021, the Houston Forensic Science Center (HFSC) received toxicological and seized drug evidence indicating the presence of 4'-chloro deschloroalprazolam. An interference study was performed to supplement the laboratory's validated benzodiazepines method for toxicological samples to differentiate alprazolam from 4'-chloro deschloroalprazolam. This study showed that while the isomers could not be chromatographically resolved using the current method, they could be differentiated based on their retention times relative to the internal standard, alprazolam-d5. Based on these findings, the HFSC toxicology laboratory reports test results as "unsuitable for analysis due to an interference" if a suspected alprazolam peak elutes before the alprazolam-d5 peak, even if all identification and quantification criteria (e.g., retention time) were acceptable. Additionally, the seized drug and toxicology laboratories re-evaluated previously analyzed alprazolam-positive casework to determine if suspected 4'-chloro deschloroalprazolam had been misidentified as alprazolam. This report presents three cases: one case with toxicological evidence indicating the presence of both 4'-chloro deschloroalprazolam and alprazolam, and two cases with both seized drug material and toxicology evidence indicating the presence of 4'chloro deschloroalprazolam with no detected alprazolam.

Evaluation of suspected drug-facilitated sexual assault cases in the city of Houston from 2014 to 2020.

Drug-facilitated sexual assault is a form of sexual violence against an individual incapacitated by alcohol and/or drugs consumed voluntarily or covertly administered. The purpose of this study was to evaluate toxicological results and the associated demographics of sexual assault-related cases submitted to Houston Forensic Science Center from 2014 to 2020. In total, 1240 samples (1230 cases) were tested during the six-year period that consisted of blood, urine, or both specimens. Blood was analyzed for ethanol by dual-column headspace gas chromatography with flame ionization detection. Drug screen analysis was performed preferably on urine specimens using enzyme-linked immunosorbent assay. Positive screening results were confirmed upon request only due to laboratory policy. A total of 22% (n = 176) of requested samples were confirmed positive. Ethanol was the most prevalent substance detected, present in 17% of the samples (n = 212), followed by 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) (n = 118). The combination of ethanol and THC-COOH was the most frequent one found (n = 17) in cases positive for two or more drugs (n = 101). Demographic data showed the majority of DFSA victims were white (25%) females (72%) with an average age of 27 years old (n = 348). Almost 90% of cases where the presence of drugs was confirmed resulted in no charges being made, either due to lack of suspect information or unknown reasons by the laboratory.

Everything Is Bigger in Texas: Alcohol Impaired Driving in Houston (2014-2018).

Driving while intoxicated (DWI) or driving under the influence of drugs (DUID) poses a continued public safety risk in Texas, which has one of the highest alcohol impaired traffic fatality rates. This study aimed to identify alcohol and drug use trends seen in DWI/DUID cases in the city of Houston from 2014 to 2018 to better understand the populations at risk. Blood samples submitted to the Houston Forensic Science Center (HFSC) were evaluated for blood alcohol concentration (BAC), drug concentrations and demographics. During the 5-year period, 12,682 Houston driver blood samples had a mean (median) BAC of 0.151 g/dL (0.167 g/dL) and age of 36.3 (34) years. Fifty percent of samples were white males. Seventy-five percent of samples were individuals aged 21 to 44 years. Between 2014 and 2018, the number of cases submitted nearly doubled, from approximately 2,000 cases per year to over 3,700. In 2014, 23% of cases submitted required further analysis per HFSC testing policy (drug screen and confirmation for DWI/DUID cases when BAC < 0.100 g/dL), which rose to 27% by 2018. Of those, 36% were polydrug cases, requiring two or more confirmation tests. Cannabinoids was the most common drug class detected (34% of cases analyzed for drugs), followed by benzodiazepines (25%), phencyclidine (20%), cocaine/metabolites (15%) and opioids (12%). Phencyclidine rose from the fifth-most commonly detected drug in 2014 to the second-most drug in 2018. Only 3% of all cases (n = 408) were negative for both alcohol and drugs. Communication between law enforcement and laboratory management is recommended to address growing caseload more effectively. The study limitations (e.g., limited scope of analysis) suggest the present data underestimated the full extent of impaired driving in Houston, indicating even more urgent needs for increasing resources and efforts to reduce this serious threat to public safety.

Recovery of oxygenated ignitable liquids by zeolites, Part II: Dual-mode heated passive headspace extraction.

Previous studies performed by our research group have suggested that zeolites are a suitable adsorbent for the recovery of oxygenates from fire debris through heated passive headspace extraction. Zeolite 13X, in particular, has been shown to be effective for recovering analytes with molecular diameters smaller than 10Å. The primary aim of this study was to evaluate the addition of zeolite 13X to heated headspace extraction for the recovery of ignitable liquids. Comparative recoveries of petroleum and alcohol-based ignitable liquid mixtures were studied utilizing activated charcoal strips and zeolites, individually and in tandem. In the presence of both adsorption media within the same sample can, activated charcoal strips recovered the majority of gasoline components, while zeolites recovered the majority of oxygenated compounds. This phenomenon was attributed to the size exclusion properties, polarity, and available surface area of zeolites. This research supports the use of zeolites with activated charcoal strips in a "dual-mode" preparation for casework in which the presence of an ignitable liquid is suspected. The described method allows for the recovery and concentration of ignitable liquid residues in a single extraction procedure, whether the ignitable liquid is petroleum-based or oxygenated in nature.