Refining the excretion factors of methadone and codeine for wastewater analysis: Combining data from pharmacokinetic and wastewater studies

Thai, Phong K., Lai, Foon Yin, Bruno, Raimondo, van Dyken, Emma, Hall, Wayne, O'Brien, Jake, Prichard, Jeremy, & Mueller, Jochen F. (2016) Refining the excretion factors of methadone and codeine for wastewater analysis: Combining data from pharmacokinetic and wastewater studies. Environment International, 94, pp. 307-314.

[img] Accepted Version (PDF 214kB)
Administrators only until September 2018 | Request a copy from author

View at publisher


Analysing drug residues in wastewater (wastewater analysis) to monitor the consumption of those drugs in the population has become a complementary method to epidemiological surveys. In this method, the excretion factor of a drug (or the percentage of drug metabolites excreted through urine) is a critical parameter for the back-estimation of the consumption of a drug. However, this parameter is usually derived from a small database of human pharmacokinetic studies. This is true for methadone and codeine, the two most commonly used opioids and also common substances of abuse. Therefore, we aimed to refine the current excretion factors used for estimating methadone and codeine by analysing published data from the literature on the excretion of methadone, its main metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and codeine. Our review included both human drug pharmacokinetic studies wastewater analysis studies. We found that while the commonly used excretion factor of methadone (~27.5%) was relatively accurate, the excretion factor of EDDP, a better biomarker for methadone consumption in sewer epidemiology, should be twice that of methadone (i.e. 55%) instead of the current equal or half values. For codeine, the excretion factor should be ~30% instead of 63.5% or 10% as previously used in wastewater analysis studies. Data from wastewater analysis studies could be used in this way to refine the excretion factors of the drugs of interest.

Impact and interest:

0 citations in Scopus
Search Google Scholar™

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 96240
Item Type: Journal Article
Refereed: Yes
DOI: 10.1016/j.envint.2016.05.033
ISSN: 0160-4120
Divisions: Current > Schools > School of Chemistry, Physics & Mechanical Engineering
Current > Institutes > Institute of Health and Biomedical Innovation
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2016 Elsevier
Copyright Statement: Licensed under the Creative Commons Attribution; Non-Commercial; No-Derivatives 4.0 International. DOI: 10.1016/j.envint.2016.05.033
Deposited On: 19 Jun 2016 23:01
Last Modified: 23 Jun 2016 07:00

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page