Transformation of codeine and codeine-6-glucuronide to opioid analogues by urine adulteration with pyridinium chlorochromate: potential issue for urine drug testing

A critical review of workplace drug testing methods for old and new psychoactive substances: Gaps, advances, and perspectives

Workplace drug testing (WDT) is essential to prevent drug abuse disorders among the workforce because it can impair work performance and safety. However, WDT is limited by many challenges, such as urine adulteration, specimen selection, and new psychoactive substances (NPS). This review examined the issues related to WDT. Various scientific databases were searched for articles on WDT for drug detection published between 1986 (when WDT started) and January 2024. The review discussed the history, importance, and challenges of WDT, such as time of specimen collection/testing, specimen adulteration, interference in drug testing, and detection of NPS. It evaluated the best methods to detect NPS in forensic laboratories. Moreover, it compared different techniques that can enhance WDT, such as immunoassays, targeted mass spectrometry, and nontargeted mass spectrometry. These techniques can be used to screen for known and unknown drugs and metabolites in biological samples. This review assessed the strengths and weaknesses of such techniques, such as their validation, identification, library search, and reference standards. Furthermore, this review contrasted the benefits and drawbacks of different specimens for WDT and discussed studies that have applied these techniques for WDT. WDT remains the best approach for preventing drug abuse in the workplace, despite the challenges posed by NPS and limitations of the screening methods. Nontargeted techniques using high-resolution liquid chromatography-mass spectrometry (MS)/gas chromatography-tandem MS can improve the detection and identification of drugs during WDT and provide useful information regarding the prevalence, trends, and toxicity of both traditional and NPS drugs. Finally, this review suggested that WDT can be improved by using a combination of techniques, multiple specimens, and online library searches in case of new NPS as well as by updating the methods and databases to include new NPS and metabolites as they emerge. To the best of the author's knowledge, this is the first review to address NPS as an issue in WDT and its application and propose the best methods to detect these substances in the workplace environment.

Advances in testing for sample manipulation in clinical and forensic toxicology - Part A: urine samples

In many countries, adherence testing is used to monitor consumption behavior or to prove abstinence. Urine and hair are most commonly used, although other biological fluids are available. Positive test results are usually associated with serious legal or economic consequences. Therefore, various sample manipulation and adulteration strategies are used to circumvent such a positive result. In these critical review articles on sample adulteration of urine (part A) and hair samples (part B) in the context of clinical and forensic toxicology, recent trends and strategies to improve sample adulteration and manipulation testing published in the past 10 years are described and discussed. Typical manipulation and adulteration strategies include undercutting the limits of detection/cut-off by dilution, substitution, and adulteration. New or alternative strategies for detecting sample manipulation attempts can be generally divided into improved detection of established urine validity markers and direct and indirect techniques or approaches to screening for new adulteration markers. In this part A of the review article, we focused on urine samples, where the focus in recent years has been on new (in)direct substitution markers, particularly for synthetic (fake) urine. Despite various and promising advances in detecting manipulation, it remains a challenge in clinical and forensic toxicology, and simple, reliable, specific, and objective markers/techniques are still lacking, for example, for synthetic urine.

Evaluation of endogenous urinary biomarkers for indirect detection of urine adulteration attempts by five different chemical adulterants in mass spectrometry methods

Reliable detection of urine adulteration attempts to circumvent positive drug testing represents a critical step for laboratories in abstinence control settings. An ideal workflow for high-throughput testing would involve simultaneous detection of adulteration attempts in the same run with drug detection. Monitoring of degraded or oxidized endogenous urinary compounds as indirect markers has been previously evaluated for that purpose exemplified for the adulterant potassium nitrite (KNO₂ ). Fifteen, previously identified endogenous markers should now be evaluated for their general applicability to detect adulteration attempts for the adulterants hypochlorite-based bleach (NaOCl), peroxidase and peroxide (H₂ O₂ ), pyridinium chlorochromate (PCC), and iodine (I₂ ). Initial experiments revealed similar results for the tested adulterants regarding degradation of indolylacryloylglycine (IAG), uric acid (UA), or UA derivatives. 5-Hydroxyisourate (HIU), the oxidation product of UA, was however only formed by KNO₂ , PCC, and H₂ O₂ . Amino acids showed larger adulterant-dependent differences. All reactions were shown to be influenced by the adulterant concentration and the urinary pH with large variances depending on compound and adulterant. Except for HIU/PCC, all markers were stable within +/- 30% variation for all adulterants at -20°C. Receiver operating characteristics indicated best sensitivity and specificity over all adulterants for IAG (specificity 0.9, sensitivity 1.0) and UA (specificity 1.0, sensitivity 0.9). HIU gave best results for KNO₂ , PCC, and H₂ O₂ and N-acetylneuraminic acid for PCC and H₂ O₂ , respectively. When integrating a limited number of targets into existing screening methods, monitoring of UA, IAG, N-acetylneuraminic acid, and HIU is recommended.

Adulterants in Urine Drug Testing

Urine drug testing plays an important role in monitoring licit and illicit drug use for both medico-legal and clinical purposes. One of the major challenges of urine drug testing is adulteration, a practice involving manipulation of a urine specimen with chemical adulterants to produce a false negative test result. This problem is compounded by the number of easily obtained chemicals that can effectively adulterate a urine specimen. Common adulterants include some household chemicals such as hypochlorite bleach, laundry detergent, table salt, and toilet bowl cleaner and many commercial products such as UrinAid (glutaraldehyde), Stealth® (containing peroxidase and peroxide), Urine Luck (pyridinium chlorochromate, PCC), and Klear® (potassium nitrite) available through the Internet. These adulterants can invalidate a screening test result, a confirmatory test result, or both. To counteract urine adulteration, drug testing laboratories have developed a number of analytical methods to detect adulterants in a urine specimen. While these methods are useful in detecting urine adulteration when such activities are suspected, they do not reveal what types of drugs are being concealed. This is particularly the case when oxidizing urine adulterants are involved as these oxidants are capable of destroying drugs and their metabolites in urine, rendering the drug analytes undetectable by any testing technology. One promising approach to address this current limitation has been the use of unique oxidation products formed from reaction of drug analytes with oxidizing adulterants as markers for monitoring drug misuse and urine adulteration. This novel approach will ultimately improve the effectiveness of the current urine drug testing programs.

Elucidation of markers for monitoring morphine and its analogs in urine adulterated with pyridinium chlorochromate

Aim: Currently, procedures that identify the drugs ‘destroyed’ in adulterated urine specimens are very limited. This study aimed to determine the effect of pyridinium chlorochromate (PCC) on routine opiate assays and identify reaction products formed. Results/methodology: Opiate-positive urines adulterated with PCC (20 and 100 mM) were analyzed using CEDIA® immunoassay and GC–MS. Urine and water samples spiked with 6-monoacetylmorphine, morphine and its glucuronides (10 µg/ml) and PCC (0.02–100 mM) were monitored with LC–MS, and the products characterized. Conclusion: PCC significantly decreased the abundance of morphine, codeine and IS. Adulterated water and urine samples containing 6-monoacetylmorphine, morphine and morphine-3-glucuronide yielded morphinone-3-glucuronide, 7,14-dihydroxy-6-monoacetylmorphine, 7,8-diketo-6-monoacetylmorphine and 7,8-diketo-morphine (tentative assignment). Reaction pathways may be different in the two matrices.

Oxidation of testosterone by permanganate and its implication in sports drug testing

Adulteration of urine with permanganate can lead to depletion of testosterone and formation of new reaction products (4α,5α- and 4β,5β-dihydroxytestosterone).

Bioanalysis of urine samples after manipulation by oxidizing chemicals: technical considerations

Drug testing programs are established to help achieve a drug-free work environment, promote fair competition in sport, facilitate harm minimization and rehabilitation programs, better manage patient care by clinicians and service law enforcement authorities. Urine remains the most popular and appropriate testing matrix for such purposes. However, urine is prone to adulteration, where chemicals, especially oxidizing chemicals, are purposely added to the collected urine specimens to produce a false-negative test result. This article will describe the effect of various popular oxidizing adulterants on urine drug test results, the countermeasures taken by laboratories in dealing with adulterated urine samples and the prospect of developing more robust and economical methods to combat urine adulteration in the future.