Picture of a black hole

Strathclyde Open Access research that creates ripples...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of research papers by University of Strathclyde researchers, including by Strathclyde physicists involved in observing gravitational waves and black hole mergers as part of the Laser Interferometer Gravitational-Wave Observatory (LIGO) - but also other internationally significant research from the Department of Physics. Discover why Strathclyde's physics research is making ripples...

Strathprints also exposes world leading research from the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

Factors affecting the fate of ciprofloxacin in aquatic field systems

Cardoza, L.A. and Knapp, C.W. and Larive, C.K. and Belden, J.B. and Lydy, M. and Graham, D.W. (2005) Factors affecting the fate of ciprofloxacin in aquatic field systems. Water, Air, and Soil Pollution, 161 (1-4). pp. 383-398.

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Ciprofloxacin (cipro) is a broad-spectrum antibiotic used in human and veterinary medicine that is readily transported into the environment via domestic wastewaters and through direct runoff. Although factors governing cipro fate are becoming understood, an integrated evaluation of disappearance mechanisms in aquatic systems has not been performed. Here we examined cipro disappearance rate in surface waters using both laboratory and field systems under different light, and dissolved (DOC) and particulate organic carbon (POC) conditions to determine when photodegradation versus adsorption dominates cipro fate. Initial laboratory experiments showed that cipro rapidly photodegraded (t(1/2) ∼ 1.5 h) with numerous photodegradation products being noted when POC levels were low. However, even moderate water column POC levels resulted in reduced photodegradation ( no breakdown products detected) and soluble cipro disappearance rates were accelerated. C-14-ciprofloxacin studies confirmed significant adsorption onto aquatic POC (KOC values of 13,900 to 20,500 L/kg at neutral pH). In contrast, a follow-up mesocosm-scale field study using low POC water showed that photodegradation could also dominate cipro fate. In conclusion, both adsorption and photodegradation strongly influence cipro fate in aquatic systems, although the dominant mechanism appears to depend upon the ambient POC level.