Microbiological water quality and derived health risks from exposure to ornamental water fountains in the city of Hannover

authored by

Estefania Carpio Vallejo, Urda Düker, Franziska Meyer, Ulrich Berding, Regina Nogueira

Abstract

Ornamental fountains are attractive urban infrastructures helping cities to cope with global warming, as water sprays have great cooling effects due to evaporative properties; however, exposure to microbiologically impaired water from ornamental fountains during recreational activities may result in adverse health outcomes for the exposed population. This study assesses the microbial water quality of four ornamental water fountains (Blätterbrunnen, Körtingbrunnen, Klaus–Bahlsen–Brunnen, and Marstallbrunnen) and performs a quantitative microbial risk assessment (QMRA) for children using Escherichia coli, Enterococci, and Salmonella to quantify the probability of gastrointestinal illnesses and Pseudomonas aeruginosa to quantify the risk of dermal infections. Samples were collected fortnightly in two campaigns in 2020 and 2021 and processed to determine bacterial concentrations. Data on exposure time were obtained during field observations on the selected fountains; a total of 499 people were observed of which 30% were children. Mean bacterial concentrations ranged from 1.6 × 10¹ to 6.1 × 10² most probable number (MPN)/100 mL for E. coli, 1.2 × 10¹–1.2 × 10³ MPN/100 mL for Enterococci, 8.6 × 10³–3.1 × 10⁵ CFU/100 mL for Salmonella, and 2.5 × 10³–3.2 × 10⁴ MPN/100 mL for P. aeruginosa. The results of the QMRA study showed that the USEPA illness rate of 36 NEEAR-gastrointestinal illnesses/1000 was exceeded for Enterococci at the Körtingbrunnen, Klaus–Bahlsen–Brunnen, and Marstallbrunnen fountains and for Salmonella and P. aeruginosa at the Körtingbrunnen fountain, suggesting that exposure to microbiologically contaminated water from ornamental fountains may pose a health risk to children. The scenario analysis shows the importance of keeping low bacterial concentrations in ornamental fountains so that the risk of illness/infection to children does not exceed the USEPA illness rate benchmark.

Organisation(s)

Institute of Sanitary Engineering and Waste Management

External Organisation(s)

Plan Zwei Stadtplanung und Architektur

Type

Article

Journal

Risk analysis

Volume

44

Pages

24-39

No. of pages

16

ISSN

0272-4332

Publication date

26.12.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Safety, Risk, Reliability and Quality, Physiology (medical)

Sustainable Development Goals

SDG 3 - Good Health and Well-being

Electronic version(s)

https://doi.org/10.1111/risa.14145 (Access: Open)