A multi-laboratory investigation of drug background levels

Contamination of a drug consumption room with drugs and potential risks for social health care workers

BACKGROUND

Studies have shown that contamination of surfaces by illicit drugs frequently occurs in forensic laboratories when manipulating seized samples as well as in pharmacies and hospitals when preparing medicinal drugs. In this project, we extended these studies to a Drug Consumption Room to investigate drug levels and possible exposure of the staff members.

METHODS

We investigated pre and post cleaning contamination by heroin and cocaine and their degradation products 6-monoacetylmorphine and benzoylecgonine on different surfaces (tables, counters, computers and door handles) and in the ambient air. We also collected urine and hair samples from staff members to check for potential short and long term contaminations.

RESULTS

Medium to heavy contamination has been detected on most surfaces and door handles; as expected, air contamination was particularly high in the smoking room. Drug levels were < LOD to very low in the urine and the hair samples of staff members tested.

CONCLUSION

The cleaning efficiency of the surfaces, carried out by staff and drug users after drug consumption, was often not satisfactory. The very low drug levels in hair indicate that acute health risks for staff members are low.

Net Weights: Visualizing and Quantifying their Contribution to Drug Background Levels in Forensic Laboratories

While the drug background in forensic laboratories has been quantified, the processes that most contribute to the background have not been extensively researched. This work presents both qualitative visualization and quantitative analysis of the spread of simulant drug particulate during the process of taking net weights. The process was modeled using three masses of powder (0.2 g, 2 g, and 100 g). The net weight process, in which the mixture was poured onto weighing paper, was mimicked and the resulting aerosolized particulate was allowed to settle. Wetted cotton swabs were then used to sample 6.45 cm² (1 in²) squares extending up to 61 cm (24 in) away from the weigh paper. The swabs were then extracted and quantified using LC-MS/MS and two-dimensional color plots were created to visualize the magnitude of particulate spread. Qualitative flow visualization of the process, accomplished using laser light sheet videography, was also completed to support the quantitative extraction experiments and provide a visual representation of the mechanism of particulate spread. Surface concentrations were found to be highest in the area immediately surrounding the weigh paper, though transport as far as 61 cm (24 in) was observed with all mass loadings. The amount of the material aerosolized and transported on the bench surrounding the weigh paper was dependent upon the mass of material being poured. These results highlight that weighing activities encountered in forensic labs may be a primary contributor to drug background and may be a potential source of inhalation exposure for chemists.

An Easy to Implement Approach for Laboratories to Visualize Particle Spread During the Handling and Analysis of Drug Evidence

Recent work has shown that detectable levels of drugs exists on nearly all surfaces within a forensic laboratory - especially within the drug chemistry unit. This is an expected occurrence due to the handling and opening of drug evidence that contains powder material. The process of opening evidence, which produces aerosolized particulate that can settle on surfaces throughout the lab, has never been visualized. This work presents the first attempt to visualize the spread of particulate throughout the laboratory during the analysis of drug evidence and introduces an easy to implement approach laboratories can use to evaluate their specific protocols. By creating two simulated bricks of drugs that contained fluorescent particles, the spread of particulate was able to be monitored throughout the evidence handling process up to and including cleaning of surfaces after analysis. The protocols in this work, showed the spread of particulate, prior to cleaning, to be quite extensive, with transfer onto surfaces and items that were handled. In this study, cleaning with methanol after processing the evidence was shown to be effective at removing nearly all particulate that was released in the process. The use of visualization techniques such as this demonstrate promise for helping laboratories identify processes in their own protocols that may contribute to drug background levels and educate forensic chemists how trace residues spread.