FACTORS AFFECTING THE DISSIPATION OF PHARMACEUTICALS IN FRESHWATER SEDIMENTS

Omar S A Al-Khazrajy, Ed Bergström, Alistair B A Boxall

Research output: Contribution to journalArticlepeer-review

Abstract

Degradation is one of the key processes governing the impact of pharmaceuticals in the aquatic environment. Most studies on the degradation of pharmaceuticals have focused on soil and sludge with fewer exploring persistence in aquatic sediments. Here we investigate the dissipation of six pharmaceuticals from different therapeutic classes in a range of sediment types. Dissipation of each pharmaceutical was found to follow first-order exponential decay. Half-lives in the sediments ranged from 9.5 d (atenolol) to 78.8 d (amitriptyline). Under sterile conditions, the persistence of pharmaceuticals was considerably longer. Stepwise multiple linear regression analysis was performed to explore the relationships between half-lives of the pharmaceuticals, sediment physicochemical properties and the sorption coefficients for the compounds. Sediment clay, silt and organic carbon content and microbial activity were the predominant factors related to the degradation rates of diltiazem, cimetidine and ranitidine. Regression analysis failed to highlight a key property which may be responsible for observed differences in the degradation of the other pharmaceuticals. The present study results suggest degradation rate of pharmaceuticals in sediments is determined by different factors and processes and does not exclusively depend on a single sediment parameter. This article is protected by copyright. All rights reserved.

Original languageEnglish
Pages (from-to)1-33
Number of pages33
JournalEnvironmental Toxicology and Chemistry
Early online date25 Oct 2017
DOIs
Publication statusE-pub ahead of print - 25 Oct 2017

Bibliographical note

© 2017 Society of Environmental Toxicology and Chemistry. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.

Keywords

  • Journal Article

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