Effects of selected pharmaceutically active compounds on the ammonia oxidizing bacterium Nitrosomonas europaea.

Journal Article (Journal Article)

Pharmaceutically active compounds (PhACs) are commonly found in wastewater influent. However, little research has focused on determining their impact on fundamental processes in wastewater treatment such as nitrogen removal. In this study, focus was placed on 4 commonly occurring PhACs (ketoprofen, naproxen, carbamazepine and gemfibrozil). Their effect was ascertained in the ammonia oxidizing bacterium (AOB), Nitrosomonas europaea in terms of membrane integrity and nitrite production. These PhACs were shown to inhibit nitrite production at concentrations of 1 and 10 μM while no effect was observed at 0.1 μM. The maximum observed nitrification inhibition was 25%, 29%, 22% and 26% for ketoprofen, naproxen, carbamazepine and gemfibrozil, respectively. A decrease in the live/dead ratio ranging from 10% to 16% suggests that these PhACs affect membrane integrity in N.europaea. The difference in nitrite production between PhACs treated cells and non PhAC treated controls was still significant following washing suggesting that inhibition is irreversible. Finally, nitrite production when adjusted to the live fraction of cells was also found to decrease suggesting that PhACs inhibited the activity of surviving cells. These results suggest that the presence of PhACs may affect AOB activity and may impact nitrogen removal, a key function in wastewater treatment. Follow up studies with additional AOB and in mixed culture are needed to further confirm these results.

Full Text

Duke Authors

Cited Authors

  • Wang, S; Gunsch, CK

Published Date

  • January 2011

Published In

Volume / Issue

  • 82 / 4

Start / End Page

  • 565 - 572

PubMed ID

  • 20980043

Electronic International Standard Serial Number (EISSN)

  • 1879-1298

International Standard Serial Number (ISSN)

  • 0045-6535

Digital Object Identifier (DOI)

  • 10.1016/j.chemosphere.2010.10.007


  • eng