Objectives: Drug abuse tests are applied to determine drug use to combat disease, crime, or substance abuse. We aimed to investigate whether cheaper and more practical plastic tubes can be an alternative to glass tubes for drug abuse analysis in urine.

Material and Methods: Paired fresh urine samples from 80 volunteers were collected into glass and plastic tubes, and drug abuse tests were analyzed in parallel after specimen validity tests. Amphetamines (AMP), benzodiazepines (BNZ), cocaine (COC), opiates (OPI), and cannabinoids (THC) were measured semi-quantitatively using the immunoassay method with the Roche Cobas c 501. Cut-off values for positivity were taken as AMP > 500 μg/L, BNZ > 300 μg/L, COC > 150 μg/L, OPI > 2000 μg/L, and THC > 50 μg/L. To investigate the effect of time, 32 of the samples were stored at room temperature for 4 hours without any preservative and reanalyzed. The SPSS 25.0 program was used to analyze the data.

Results: There were no significant differences between glass and plastic tubes in AMP, BNZ, COC, OPI, and THC concentrations. A statistically significant difference was found for OPI (p = 0.005), but the difference in OPI levels did not change the clinical decision. There were high correlations between all results for the same analyte measurements in both tubes (p = 0.0001). Additionally, 4-hour storage at room temperature did not cause degradation or adsorption of any drug.

Conclusion: As a result of this study, it can be concluded that plastic tubes can be used instead of glass tubes in the analysis of drugs of abuse, with no significant change in substance concentrations after storage for four hours at room temperature.