A survey of the effects of common illicit drugs on forensic DNA analysis

A systematic approach to the analysis of illicit drugs for DNA with an overview of the problems encountered

Due to the restricted nature of illicit drugs, it is difficult to conduct research surrounding the analysis of this drug material for any potential DNA in sufficient quantities acceptable for high numbers of replicates. Therefore, the current research available in peer reviewed journals thus far regarding analysing illicit drugs for DNA has been performed under varying experimental conditions, often using surrogate chemicals in place of illicit drugs. The data presented within this study originated from the analysis of genuine illicit drugs prepared both in controlled environments and those seized at the Australian border (and therefore from an uncontrolled environment) to determine if DNA can be obtained from this type of material. This study has been separated into three main parts (total n=114 samples): firstly, methamphetamine synthesised within a controlled environment was spiked with both saliva and trace DNA to determine the yield following DNA extraction; secondly, methamphetamine also synthesised in a controlled environment but on a larger scale was tested for the amount of DNA added incidentally throughout the synthesis, including the additional steps of recrystallising, homogenising and "cutting" the drug material to simulate preparation for distribution; and thirdly, the detection of human DNA within samples of cocaine and heroin seized at the Australian border. The DNA Fast Flow Microcon Device was utilised to concentrate all replicates from the same source into one combined extract to improve the DNA profiles for the samples where no DNA spiking occurred. Full STR profiles were successfully obtained from drug samples spiked with both saliva and trace DNA. Methamphetamine was present in the final DNA extracts and caused incompatibilities with the quantification of DNA using Qubit. The yields of DNA from drugs not spiked with DNA sources were much lower, resulting in 36 % of samples yielding alleles where all others did not. These results were not unexpected given these were realistic drug samples where the history of the drug material was unknown. This is the first study to obtain DNA profiles from genuine illicit drug material in both controlled and uncontrolled environments and indicates that the analysis of illicit drugs for DNA is an avenue worth pursuing to provide information which can in turn assist with disrupting the supply of these drugs. Given that DNA profiling is carried out worldwide using essentially the same systems as described within this study, the potential for impact is on a national and international scale.

Comparison of three DNA extraction methods tested on illicit drug-related powders

The detection of human DNA on and within illicit drug preparations is novel and a focus of current research. Previous studies have indicated that certain drug-related powders present in illicit drug preparations can interfere with downstream DNA analysis when directly added to the PCR. Therefore, it is important to determine if these drug-related powders are effectively removed during the DNA extraction or whether traces of powder remain to interfere with DNA processing. Three extraction methods were selected to assess their efficiency at removing drug-related powders for downstream processes using DNA from both saliva and touch depositions. This is the first study to compare efficiencies of DNA extraction methods from drug-related powders. The extraction methods compared were the DNA IQ™ System, the QIAamp® DNA Investigator Kit and the combination of a simple lysis step followed by use of the Microcon® DNA Fast Flow device. Saliva was added to dimethylsulfone (DMS), nitrostyrene and PROSOLV® tablet mixture to determine the effect of powder type (based on solubility). Saliva was also added to 0, 50, 200 and 400 mg of DMS to determine the effect of an increase in DMS quantity. Trace DNA was deposited onto DMS using a worn glove approach. These samples were re-tested six months post-DNA deposition and profiled for further comparisons. Ten replicates were conducted for each condition with five replicates of saliva positive controls per method (n = 255 samples). A subset of samples was chemically analysed to determine if DMS was present in the final DNA eluant. The readily soluble DMS did not interfere with any of the extraction methods at lower amounts, however increasing the DMS to 400 mg reduced the relative DNA yields using the Microcon® and Investigator methods. The tablet mixture reduced the relative DNA yield of all three methods, however the nitrostyrene (which was relatively insoluble) only reduced the relative DNA yield of the DNA IQ™. The Investigator method performed the best with the trace samples, followed by the Microcon® method and then the DNA IQ™. DMS was detected in all extracts chemically analysed from the DNA IQ™ and Microcon®, whereas only one sample tested from the Investigator kit contained DMS in the extract and was in a relatively low amount compared to the other samples. Not one kit outperformed the others in all comparisons, however the Investigator kit was the most efficient overall at optimising the DNA yield whilst also removing the powders more effectively.

Perspectives of people in Philadelphia who use fentanyl/heroin adulterated with the animal tranquilizer xylazine; Making a case for xylazine test strips

Background

Xylazine is an animal tranquilizer increasingly detected in those who have died of an opioid overdose in Philadelphia, PA and elsewhere. Despite an increasing presence of xylazine in the local fentanyl/heroin drug market and its association with ulcers, there are few perspectives about xylazine from people who use drugs and no data about the utility of a hypothetical xylazine test strip.

Methods

Between January to May 2021 in Philadelphia, PA, people who used fentanyl/heroin and had previously used fentanyl test strips were queried about xylazine and hypothetical xylazine test strips. Interviews were transcribed and analysis was conducted via conventional content analysis.

Results

Participants (7 spontaneously, 6 after probing, n = 13) discussed "tranq" (i.e., xylazine) in the fentanyl/heroin supply. None enjoyed tranq or wanted it in their fentanyl/heroin. Participants suspected xylazine saturation of the fentanyl/heroin market, disliked the sensation of the drug, and had safety concerns about xylazine exposure. Participants did not indicate concerns about overdose. All were interested in hypothetical xylazine test strips. While previous literature indicates that some people enjoy tranq in their fentanyl/heroin, our findings differed, with participants expressing concern about the consequences of undesired exposure. The interest expressed for xylazine test strips by people who use fentanyl/heroin is an important opportunity to center their voices in the development of innovations designed to mitigate the harms of unwanted adulterant exposure.

Conclusions

In the present study, people who use fentanyl/heroin indicated an interest to test their drug for the presence of xylazine prior to use.