Adsorption and transformation of selected human-used macrolide antibacterial agents with iron(III) and manganese(IV) oxides

• Published in: Environmental pollution (1987) 2009-04, Vol.157 (4), p.1317-1322
• Main Authors: Feitosa-Felizzola, Juliana, Hanna, Khalil, Chiron, Serge
• Format: Article
• Language: English
• Subjects: Adsorption; Adsorption/transformation; Aluminum Silicates; Anti-Bacterial Agents - chemistry; Applied sciences; Biodegradation, Environmental; Biological and physicochemical phenomena; Clarithromycin - chemistry; Earth sciences; Earth, ocean, space; Ecology - methods; Engineering and environment geology. Geothermics; Environmental fate; Exact sciences and technology; Ferric Compounds - chemistry; hydrolysis; iron oxyhydroxides; macrolide antibiotics; Macrolides; Macrolides - chemistry; manganese; Manganese Compounds - chemistry; Natural water pollution; Oxides - chemistry; Oxy-hydroxides; Pollution; Pollution, environment geology; reaction kinetics; Roxithromycin - chemistry; sediment contamination; Soil - analysis; Soil Pollutants - chemistry; Surface Properties; Surface reaction; water pollution; Water treatment and pollution
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2008.11.048

The adsorption/transformation of two members (clarithromycin and roxithromycin) of the macrolide (ML) antibacterial agents on the surface of three environmental subsurface sorbents (clay, iron(III) and manganese(IV) oxy-hydroxides) was investigated. The adsorption fitted well to the Freundlich model with a high sorption capacity. Adsorption probably occurred through a surface complexation mechanism and was accompanied by slow degradation of the selected MLs. Transformation proceeded through two parallel pathways: a major pathway was the hydrolysis of the cladinose sugar, and to a lesser extent the hydrolysis of the lactone ring. A minor pathway was the N-dealkylation of the amino sugar. This study indicates that Fe(III) and Mn(IV) oxy-hydroxides in aquatic sediments may play an important role in the natural attenuation of MLs. Such an attenuation route yields a range of intermediates that might retain some of their biological activity. Iron(III) and manganese(IV) oxy-hydroxides in aquatic sediments may play an important role in the natural attenuation of macrolide antibacterial agents.