Passive exposure to cocaine on a professional level: Importance of considering relevant interpretation parameters

The aim of this study was to evaluate the extend passive exposure in hair from professionals working contact with cocaine seizures, considering cleaning procedures, segmentation and interpretation recommendations consensus on drug testing [https://soht.org/images/pdf/Consensus_DoA_2021.pdf] recent literature. In forensic casework where analysis is requested, experts have answer question if concentrations found are due an active use or rather a contamination. preliminary study, impact (chronic) evaluated by analyzing subjects professional level (laboratory technicians law enforcement dealing clandestine laboratories). depending specific tasks dismantling laboratories (high) treatment large quantities samples (medium) few grams those laboratory (low). Head collected 7 volunteers. A total 19 were at different time periods [number (n): high = 4; medium: n 9; low: 6]. Hair cut segments, decontaminated our routine method using dichloromethane, water methanol, extracted [Ramirez Fernandez MdM, Di Fazio V, Wille SM, Kummer N, Samyn N. J Chromatogr B Analyt Technol Biomed Life Sci 2014;965:7–18.]. last wash also kept for analysis. An extended washing procedure evaluated. analysed cocaine, benzoylecgonine, norcocaine, cocaethylene, m-OH-benzoylecgonine, methylecgonine. Five test provided us urine sample two days after manipulation. results median (pg/mg) minimum maximum value according as follows: – (A) hair; (B) ratio benzoylecgonine/cocaine (C) norcocaine/cocaine (D) hair/wash: high: (682; 36–7045); B: 0.07; (0.05–0.11); C: 0.023; (0.009–0.031); D: 2.23; (0.5–31), (92; < LOQ(32)-489); (0,92;0.13–5.49); LOQ (< LOQ); D (9; 6.7–10,5), [56; LOQ(32)-189]; [0.16; 0,16–0.16 (only one value)]; (1.51; 1.0–4.7). Increasing detected root tip when longhair strands analysed, both washes. For exposure, above recommended cut-offs (> 500 pg/mg) relatively benzoylecgonine (up 716 norcocaine 342 detected. cases medium low negative traces all methylecgonine, m-OH-benzoylecgonine (LOQ 1–3 pg/mg). Regarding washing, contaminated presented highest washes 10%). Extended procedures did not improve results. All European Workplace Drug (100 ng/mL) proving no use. obtained show good correlation between hair. This demonstrates that cut-off values should be applied sole criterion. Following other parameters mandatory considered too: case context, cut-off-values, versus metabolites, ratios, presence more metabolites such hydroxy metabolites.