Enhancing drug checking services for supply monitoring: perspectives on implementation in syringe service programs in the USA.

BACKGROUND: Shifts in the US drug supply, including the proliferation of synthetic opioids and emergence of xylazine, have contributed to the worsening toll of the overdose epidemic. Drug checking services offer a critical intervention to promote agency among people who use drugs (PWUD) to reduce overdose risk. Current drug checking methods can be enhanced to contribute to supply-level monitoring in the USA, overcoming the selection bias associated with existing supply monitoring efforts and informing public health interventions. METHODS: As a group of analytical chemists, public health researchers, evaluators, and harm reductionists, we used a semi-structured guide to facilitate discussion of four different approaches for syringe service programs (SSPs) to offer drug checking services for supply-level monitoring. Using thematic analysis, we identified four key principles that SSPs should consider when implementing drug checking programs. RESULTS: A number of analytical methods exist for drug checking to contribute to supply-level monitoring. While there is likely not a one-size-fits-all approach, SSPs should prioritize methods that can (1) provide immediate utility to PWUD, (2) integrate seamlessly into existing workflows, (3) balance individual- and population-level data needs, and (4) attend to legal concerns for implementation and dissemination. CONCLUSIONS: Enhancing drug checking methods for supply-level monitoring has the potential to detect emerging threats in the drug supply and reduce the toll of the worsening overdose epidemic.

Per- and Polyfluoroalkyl Substances in Canadian Fast Food Packaging.

A suite of analytical techniques was used to obtain a comprehensive picture of per- and polyfluoroalkyl substances (PFAS) in selected Canadian food packaging used for fast foods (n = 42). Particle-induced gamma ray emission spectroscopy revealed that 55% of the samples contained <3580, 19% contained 3580-10 800, and 26% > 10 800 µg F/m2. The highest total F (1 010 000-1 300 000 µg F/m2) was measured in molded "compostable" bowls. Targeted analysis of 8 samples with high total F revealed 4-15 individual PFAS in each sample, with 6:2 fluorotelomer methacrylate (FTMAc) and 6:2 fluorotelomer alcohol (FTOH) typically dominating. Up to 34% of the total fluorine was released from samples after hydrolysis, indicating the presence of unknown precursors. Nontargeted analysis detected 22 PFAS from 6 different groups, including degradation products of FTOH. Results indicate the use of side-chain fluorinated polymers and suggest that these products can release short-chain compounds that ultimately can be transformed to compounds of toxicological concern. Analysis after 2 years of storage showed overall decreases in PFAS consistent with the loss of volatile compounds such as 6:2 FTMAc and FTOH. The use of PFAS in food packaging such as "compostable" bowls represents a regrettable substitution of single-use plastic food packaging.

Current attitudes toward drug checking services and a comparison of expected with actual drugs present in street drug samples collected from opioid users.

BACKGROUND: The opioid epidemic continues to be associated with high numbers of fatalities in the USA and other countries, driven mainly by the inclusion of potent synthetic opioids in street drugs. Drug checking by means of various technologies is being increasingly implemented as a harm reduction strategy to inform users about constituent drugs in their street samples. We assessed how valued drug checking services (DCS) would be for opioid street drug users given the ubiquity of fentanyl and related analogs in the drug supply, the information they would most value from drug checking, and compared expected versus actual constituent drugs in collected samples. METHODS: A convenience sample of opioid street drug users (N = 118) was recruited from two syringe service exchange programs in Chicago between 2021 and 2022. We administered brief surveys asking about overdose history, whether fentanyl was their preferred opioid, and interest in DCS. We also collected drug samples and asked participants what drug(s) they expected were in the sample. Provided samples were analyzed using LC-MS technology and the results compared to their expected drugs. RESULTS: Participants reported an average of 4.4 lifetime overdoses (SD = 4.8, range = 0-20) and 1.1 (SD = 1.8, range = 0-10) past-year overdoses. A majority (92.1%) believed they had recently used drugs containing fentanyl whether intentionally or unintentionally. Opinions about the desirability of fentanyl were mixed with 56.1% indicating they did not and 38.0% indicating they did prefer fentanyl over other opioids, mainly heroin. Attitudes toward DCS indicated a general but not uniform receptiveness with a majority indicating interest in DCS though sizeable minorities believed DCS was "too much trouble" (25.2%) or there was "no point" in testing (35.4%). Participants were especially inaccurate identifying common cutting agents and potentiating drugs such as diphenhydramine in their samples (sensitivity = .17). CONCLUSIONS: Results affirmed street drug users remain interested in using DCS to monitor their drugs and such services should be more widely available. Advanced checking technologies that provide information on the relative quantities and the different drugs present in a given sample available at point-of-care, would be most valuable but remain challenging to implement.

Development and validation of a liquid chromatography tandem mass spectrometry method for the analysis of 53 benzodiazepines in illicit drug samples.

An LC-MS/MS method for the analysis of 53 benzodiazepines, including various designer benzodiazepines, was developed. The developed method was applied to a total of 79 illicit street drug samples collected in Chicago, IL. Of these samples, 68 (84%) had detectable amounts of at least one benzodiazepine. Further, of the 53 benzodiazepines included in the developed method just 14 were measured in samples. Clonazolam, a potent designer benzodiazepine and derivative of clonazepam, was the most frequently measured benzodiazepine in 63% of samples and was measured in the highest concentrations. Other benzodiazepines measured in more than 10% of samples included clonazepam, alprazolam, flualprazolam, and oxazepam. Mixtures of benzodiazepines were frequently measured in samples, with just 24% of samples containing just one benzodiazepine. To determine the response of benzodiazepines on a rapid, point-of-use drug checking tool, all 53 benzodiazepine standards were screened on a lateral flow immunoassay benzodiazepine test strip. Sixty eight percent of standards gave a positive BTS response at a concentration of 20 µg/mL, demonstrating BTS have response to a wide variety of benzodiazepines, including many designer benzodiazepines. A comparison of this data to previous data reported for the same samples demonstrated all samples containing a benzodiazepine also had an opioid present, with fentanyl being present in 94% of benzodiazepine samples. These results highlight high rates of polysubstance drug presence in Chicago, IL illicit drug samples, posing an increased risk of drug overdoses in people who use drugs.

Occurrence and biomagnification of perfluoroalkyl substances (PFAS) in Lake Michigan fishes.

We measured perfluoroalkyl substances (PFAS) in prey and predator fish from Lake Michigan (USA) to investigate the occurrence and biomagnification of these compounds in this important ecosystem. Twenty-one PFAS were analyzed in 117 prey fish obtained from sites across Lake Michigan and in 87 salmonids collected in four lake quadrants. The mean concentration of sum (∑) PFAS above the method detection limit was 12.7 ± 6.96 ng g-1 wet weight in predator fish (all of which were salmonids) and 10.7 ± 10.4 ng g-1 in prey fish, with outlier levels found in slimy sculpin, Cottus cognatus (187 ± 12.2 ng g-1 ww). Perfluorooctanoic sulfonic acid (PFOS) was the most frequently detected and most abundant compound of the 21 PFAS, occurring in 98 % of individuals with a mean concentration of 9.86 ± 6.36 ng g-1 ww without outliers. Perfluoroalkyl carboxylates (PFCA) concentrations were higher in prey fish than in predators, with some compounds such as perfluorooctanoic acid (PFOA) being detected in higher frequency in prey fish. Besides PFOS, detection of several long-chain (C8-C12) PFCAs were observed in >80 % of the prey fish. Overall, the observed concentrations in Lake Michigan fish were lower than those reported in other Laurentian Great Lakes except for Lake Superior. Biomagnification factors (BMFs) for PFOS exceeded 1.0 (range, 1.80 to 5.12) in all predator-prey relationships analyzed, indicating biomagnification of these compounds, whereas BMFs of other long-chain PFCAs varied according to the fish species. PFAS were found in all fish species measured from Lake Michigan and commonly biomagnified from prey to predator fish, strongly suggesting a dietary connection.

Validated method for the analysis of 22 illicit drugs and their metabolites via liquid chromatography tandem mass spectrometry (LC-MS/MS) in illicit drug samples collected in Chicago, IL.

Drug checking services are being utilized worldwide to provide people who use drugs information on the composition and contents of their drugs as a tool for harm reduction and accidental overdose prevention. Existing drug checking services use a variety of techniques including immunoassay strips and spectroscopic techniques like FTIR and Raman. Few services utilize LC-MS based methods for primary or secondary analysis and few methods exist for direct analysis of illicit drugs. To address this, an LC-MS/MS method was developed for 22 illicit drugs and cutting agents using LC-MS/MS with application to 124 illicit drug samples that were collected from Chicago, IL. Samples were also analyzed using fentanyl and benzodiazepine immunoassay test strips. Fentanyl test strips gave a positive result for 86% of samples with only one sample showing a positive result on a benzodiazepine test strip. LC-MS/MS analysis of samples show that opioids were the most commonly quantified in 96% of samples, followed by stimulants at 12% and benzodiazepines at 1%. Fentanyl was measured in 91% of samples, co-occurring with heroin in 58% of opioid-containing samples. A comparison of the gold-standard LC-MS/MS results to fentanyl test strips shows a high level of accuracy for the fentanyl test strips, with just 5% of samples being classified as false negatives and no false positives. These results demonstrate the strengths and benefits of LC-MS/MS when incorporated as a secondary analysis tool for drug checking.

Per- and Polyfluoroalkyl Substances in North American School Uniforms.

We analyzed 72 children's textile products marketed as stain-resistant from US and Canadian stores, particularly school uniforms, to assess if clothing represents a significant route of exposure to per- and polyfluoroalkyl substances (PFAS). Products were first screened for total fluorine (total F) using particle-induced γ-ray emission (PIGE) spectroscopy (n = 72), followed by targeted analysis of 49 neutral and ionic PFAS (n = 57). PFAS were detected in all products from both markets, with the most abundant compound being 6:2 fluorotelomer alcohol (6:2 FTOH). Total targeted PFAS concentrations for all products collected from both countries ranged from 0.250 to 153 000 ng/g with a median of 117 ng/g (0.0281-38 100 µg/m2, median: 24.0 µg/m2). Total targeted PFAS levels in school uniforms were significantly higher than in other items such as bibs, hats, stroller covers, and swimsuits, but comparable to outdoor wear. Higher total targeted PFAS concentrations were found in school uniforms made of 100% cotton than synthetic blends. Perfluoroalkyl acids (PFAAs) precursors were abundant in school uniforms based on the results of hydrolysis and total oxidizable precursor assay. The estimated median potential children's exposure to PFAS via dermal exposure through school uniforms was 1.03 ng/kg bw/day. Substance flow analysis estimated that ∼3 tonnes/year (ranging from 0.05 to 33 tonnes/year) of PFAS are used in US children's uniforms, mostly of polymeric PFAS but with ∼0.1 tonne/year of mobile, nonpolymeric PFAS.

Rapid, instrument-free colorimetric quantification of DNA using Nile Blue.

The use of nucleic acid tests (NAT) for sensitive and rapid detection of pathogens relevant to human health has increased due to the ubiquity of nucleic acid amplification techniques such as polymerase chain reaction. The use of such tools for detection of amplified nucleic acid (NA) in field and clinical settings is limited by the need for complex instrumentation and trained users. To address these limitations we developed a rapid, robust, and instrument-free colorimetric detection method for nucleic acids using a visible region dye, Nile Blue (NB). NB is a cationic benzophenoxazine dye with well-known binding interactions with NA and has been used in instrumental methods for DNA quantification. When combined with dsDNA, the color of NB shifts from blue to purple. Images of this color shift are collected and are subjected to image analysis. Observed changes in the red and green colorimetric intensities are linked to the ratio of dsDNA to NB. By titrating solutions of dsDNA against a series of NB concentrations, we found it possible to quantitate dsDNA at concentrations ranging from 10-100 µg mL-1 using a k-means cluster analysis method. This range is comparable to that of NA concentrations quantified using gold-standard UV-Visible spectroscopy and to the concentrations of NA in biological samples after amplification. Unknown concentrations of dsDNA from yeast extracts were correctly identified within ±5 µg mL-1 of true concentration. Preliminary experiments demonstrate use of the developed NB method on paper-based analytical devices. As an instrument-free detection method, NB allows for rapid and robust quantification of dsDNA in field settings.

Electrolysis Activation of Fused-Filament-Fabrication 3D-Printed Electrodes for Electrochemical and Spectroelectrochemical Analysis.

Following the expiration of the patents on fused-filament-fabrication (FFF), the availability and uses of this 3D-printing technology have exploded. Several recent reports describe how conductive composites can be used with FFF printers to generate 3D-printed electrodes (3DEs) for energy storage and electrochemical analysis. As printed materials, these electrodes have very high impedance values because of the high content of insulating thermoplastic required for FFF printers. To overcome this challenge, deposition of metals or activation with harsh chemicals has previously been employed. Here, a benign postprinting process was developed using the electrolysis of water to selectively remove the insulating thermoplastic (polylactic acid) via saponification. Optimization of the hydroxide-treatment process was found to reduce the impedance of 3DEs by 3 orders of magnitude in filaments from two manufacturers. This electrolysis-activation strategy offers a safe, accessible, and affordable means for improving the electrochemical performance of 3DEs. Here, the ability of these modified 3DEs to be used for electrochemical analysis and integrated into complex electrochemical cells is demonstrated.

3D Printed UV-Visible Cuvette Adapter for Low-Cost and Versatile Spectroscopic Experiments.

Ultraviolet-visible (UV-vis) spectroscopy represents one of the most popular analytical techniques in chemical research labs. A variety of vendors provide instruments that are suited for the analysis of liquid samples at moderate concentrations. However, to accommodate more specialized experiments, expensive accessories are required and often do not fit the specific needs of experimental scientists. In this work, we present a generalized adapter that can be 3D printed and used with existing spectrometers to enable a wide array of experiments to be performed. In the case of liquid samples, we provide a method for dramatically reducing the price of a quartz cuvette with minimal impact on performance. Through simple modification of the design, cuvettes with various path lengths can be prepared. Additionally, we illustrate the ability to turn any sample container into a working cuvette to simplify experimental protocols, prevent contamination risks, and further reduce costs. This strategy also enables gaseous and solid samples to be evaluated easily and reproducibly. Furthermore, we demonstrate how this concept can be extended to interface additional instrumentation with a commercial UV-vis spectrometer. All of the digital designs are provided under a creative commons license to enable other researchers to modify and adapt the designs for their unique experimental requirements.