Effects of pharmaceutical mixtures in aquatic microcosms

• Published in: Environmental toxicology and chemistry Vol. 23; no. 4; pp. 1035 - 1042
• Main Authors: Richards, Sean M., Wilson, Christian J., Johnson, David J., Castle, Dawn M., Lam, Monica, Mabury, Scott A., Sibley, Paul K., Solomon, Keith R.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Periodicals, Inc 01-04-2004; SETAC
• Subjects: Animal, plant and microbial ecology; Animals; Anti-Infective Agents - toxicity; Anti-Inflammatory Agents, Non-Steroidal - toxicity; Applied ecology; Aquatic ecosystem; Araceae; Biological and medical sciences; Ciprofloxacin - toxicity; Dose-Response Relationship, Drug; Drug Interactions; Ecosystem; Ecotoxicology, biological effects of pollution; Fishes; Fluoroquinolone; Fluoxetine - toxicity; Food Chain; Fresh water environment; Fundamental and applied biological sciences. Psychology; General aspects; Ibuprofen - toxicity; Lemna gibba; Microcosms; Multivariate Analysis; Myriophyllum; Pharmaceutical; Phytoplankton; Plankton; Population Dynamics; Risk Assessment; Serotonin Uptake Inhibitors - toxicity; Water Microbiology; Water Pollutants, Chemical - toxicity; Zooplankton; Ecotoxicology; Pharmaceutical Fluoroquinolone Aquatic ecosystem Microcosms Plankton; Toxicity; Microcosm
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1897/02-616

Pharmaceuticals have a wide range of biological properties and are released into the environment in relatively large amounts, yet little information is available regarding their effects or potential ecological risks. We exposed outdoor aquatic microcosms to combinations of ibuprofen (a nonsteroidal anti‐inflammatory drug), fluoxetine (a selective serotonin reuptake inhibitor), and ciprofloxacin (a DNA gyrase—inhibiting antibiotic) at concentrations of 6, 10, and 10 μg/L, respectively (low treatment [LT]); 60, 100, and 100 μg/L, respectively (medium treatment [MT]); and 600, 1,000, and 1,000 μg/L, respectively (high treatment [HT]). We maintained these concentrations for 35 d. Few responses were observed in the LT; however, effects were observed in the MT and HT. Fish mortality occurred in the MT (<35 d) and in the HT (<4 d). Phytoplankton increased in abundance and decreased in diversity (number of taxa) in the HT, with consistent trends being observed in the MT and LT. Zooplankton also showed increased abundance and decreases in diversity in the HT, with consistent trends being observed in the MT. Multivariate analyses for zooplankton and phytoplankton suggested interactions between these communities. Lemna gibba and Myriophyllum spp. showed mortality in the HT; growth of L. gibba was also reduced in the MT. Bacterial abundance did not change in the HT. All responses were observed at concentrations well below the equivalent pharmacologically active concentrations in mammals. Although the present data do not suggest that ibuprofen, fluoxetine, and ciprofloxacin are individually causing adverse effects in surface‐water environments, questions remain about additive responses from mixtures.