Abstract

Aquatic pollution with faecal bacteria and subsequent consumption of contaminated water or food is a worldwide issue that causes severe health effects (e.g. meningitis, salmonellosis, dysentery). In addition, the excessive use of antibiotics in animal husbandry and human medicine has enhanced the selective pressure on pathogenic bacteria, further increasing human health risks and detrimental effects on natural microbial communities. This urges the need to monitor faecal contamination using a time-integrated approach, as grab water samples can miss pathogen peaks. We tested the ability of zebra mussels (Dreissena polymorpha) to take up and depurate faecal indicator bacteria such as Escherichia coli and intestinal enterococci. Furthermore, we quantified the frequency of antibiotic resistant bacteria in water and mussels both in controlled laboratory tests and under in situ conditions downstream of a sewage treatment plant (STP). Laboratory results show that bacterial indicators in mussels were 132 times higher than their concentration in water, and that mussels retained bacteria up to 2 days after pulse exposure. Field results show decreasing bacterial concentrations in both water and mussels downstream the STP, with maximum E. coli concentrations ranging 173-9 cfu mL(-1) in water and 2970-330 cfu g(-1) in mussels. Similarly, enterococci ranged 59-4 cfu mL(-1) and 1450-240 cfu g(-1) in water and mussels, respectively. High proportions of antibiotic resistant E. coli were found in mussels (72%) and water (65%), and slightly lower proportion of resistant enterococci was found in mussels (47%) and in water (34%). Moreover, 33% of the bacteria isolated from mussels were resistant to multiple antibiotics, which emphasizes that resistance is a common feature in surface waters and highlights the need for safe water management. Our results show that zebra mussels provide an efficient, time-integrating tool for quantifying faecal indicators, including resistant and multidrug resistant bacteria. (C) 2018 The Authors. Published by Elsevier B.V.

Keywords

Faecal; Pathogen; In situ; Escherichia coli; Enterococcus; Salmonella

Published in

Science of the Total Environment
2019, Volume: 650, number: Part 2, pages: 2141-2149
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Bighiu, Maria

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Norman Haldén, Anna

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Goedkoop, Willem

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

Associated SLU-program

AMR: Bacteria


Sustainable Development Goals

Ensure availability and sustainable management of water and sanitation for all
Ensure healthy lives and promote well-being for all at all ages
End hunger, achieve food security and improved nutrition and promote sustainable agriculture


UKÄ Subject classification

Environmental Sciences


Publication identifier

DOI: https://doi.org/10.1016/j.scitotenv.2018.09.314

Permanent link to this page (URI)

https://res.slu.se/id/publ/96976