
Keywords: اپیدمیولوژی مواد مخدر; LOD; limit of detection; LOQ; limit of quantification; KM; Kaplan-Meier estimate; MLE; Maximum Likelihood Estimation; WWTP; wastewater treatment plant; ACS; American Community Survey; RSD; relative standard deviation; MDMA; 3,4 methylenedioxymethamphetami