{"title":"Prevalence of antibiotic-resistant enterobacteriaceae in domestic wastewater and associated health risks in reuse practices","authors":"","doi":"10.1016/j.ijheh.2024.114478","DOIUrl":null,"url":null,"abstract":"<div><div>The use of wastewater for non-potable purposes is an important alternative for addressing water scarcity, especially in developing regions. However, minimizing the risks, particularly those associated with emerging contaminants that may induce resistance among pathogens in wastewater, is crucial. This study assessed the occurrence of antibiotic-resistant bacteria in untreated wastewater used for agricultural purposes and evaluated the quantifiable health risks associated with this practice in Tamale, Ghana. The resistance of some Enterobacteriaceae, such as <em>E. coli, Klebsiella, and Salmonella-Shigella,</em> to four commonly used antibiotics in Ghana was assessed using a conventional microbiological culture approach and the Kirby Bauer disk diffusion method. A Quantitative Microbial Risk Assessment (QMRA) was performed to estimate the health risks associated with two distinct scenarios of wastewater reuse: (1) accidental ingestion of contaminated wastewater and soil, and (2) consumption of vegetables irrigated with wastewater. This approach applied a Monte Carlo simulation based on 10,000 interactions and identified <em>E. coli</em> O157:H7 as the reference pathogen. Among Enterobacteriaceae, <em>Klebsiella pneumoniae, Salmonella-Shigella</em> and <em>E. coli</em> were isolated, in concentrations exceeding the limit recommended by the World Health Organization (10<sup>3</sup> CFU/100 ml). All the isolated bacteria were resistant to metronidazole (5 μg). Thirty-three per cent of <em>Klebsiella pneumoniae</em> isolates were intermediate/moderately susceptible, and all other bacteria were resistant to amoxicillin (30 μg). All <em>Klebsiella pneumoniae</em> and the majority of <em>Salmonella-Shigella</em> (69.8 %) isolates were resistant to trimethoprim-sulfamethoxazole (25 μg) and tetracycline (30 μg). When assessing health risks, the mean annual probability of infection associated with consuming vegetables irrigated with wastewater varied between 5.14 × 10<sup>−2</sup> and 9.79 × 10<sup>−1</sup> per person per year. Conversely, for the accidental ingestion scenario, the probability was 1.00 per person per year. In these scenarios, the probability of illness ranged from 1.29 × 10<sup>−2</sup> to 2.4 × 10<sup>−1</sup> and 2.5 × 10<sup>−1</sup> per person per year. The health risks posed by these findings surpass the maximum threshold prescribed by the World Health Organization, thereby emphasizing the need for prompt mitigation strategies.</div></div>","PeriodicalId":13994,"journal":{"name":"International journal of hygiene and environmental health","volume":null,"pages":null},"PeriodicalIF":4.5000,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International journal of hygiene and environmental health","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1438463924001597","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"INFECTIOUS DISEASES","Score":null,"Total":0}
引用次数: 0
Abstract
The use of wastewater for non-potable purposes is an important alternative for addressing water scarcity, especially in developing regions. However, minimizing the risks, particularly those associated with emerging contaminants that may induce resistance among pathogens in wastewater, is crucial. This study assessed the occurrence of antibiotic-resistant bacteria in untreated wastewater used for agricultural purposes and evaluated the quantifiable health risks associated with this practice in Tamale, Ghana. The resistance of some Enterobacteriaceae, such as E. coli, Klebsiella, and Salmonella-Shigella, to four commonly used antibiotics in Ghana was assessed using a conventional microbiological culture approach and the Kirby Bauer disk diffusion method. A Quantitative Microbial Risk Assessment (QMRA) was performed to estimate the health risks associated with two distinct scenarios of wastewater reuse: (1) accidental ingestion of contaminated wastewater and soil, and (2) consumption of vegetables irrigated with wastewater. This approach applied a Monte Carlo simulation based on 10,000 interactions and identified E. coli O157:H7 as the reference pathogen. Among Enterobacteriaceae, Klebsiella pneumoniae, Salmonella-Shigella and E. coli were isolated, in concentrations exceeding the limit recommended by the World Health Organization (103 CFU/100 ml). All the isolated bacteria were resistant to metronidazole (5 μg). Thirty-three per cent of Klebsiella pneumoniae isolates were intermediate/moderately susceptible, and all other bacteria were resistant to amoxicillin (30 μg). All Klebsiella pneumoniae and the majority of Salmonella-Shigella (69.8 %) isolates were resistant to trimethoprim-sulfamethoxazole (25 μg) and tetracycline (30 μg). When assessing health risks, the mean annual probability of infection associated with consuming vegetables irrigated with wastewater varied between 5.14 × 10−2 and 9.79 × 10−1 per person per year. Conversely, for the accidental ingestion scenario, the probability was 1.00 per person per year. In these scenarios, the probability of illness ranged from 1.29 × 10−2 to 2.4 × 10−1 and 2.5 × 10−1 per person per year. The health risks posed by these findings surpass the maximum threshold prescribed by the World Health Organization, thereby emphasizing the need for prompt mitigation strategies.
期刊介绍:
The International Journal of Hygiene and Environmental Health serves as a multidisciplinary forum for original reports on exposure assessment and the reactions to and consequences of human exposure to the biological, chemical, and physical environment. Research reports, short communications, reviews, scientific comments, technical notes, and editorials will be peer-reviewed before acceptance for publication. Priority will be given to articles on epidemiological aspects of environmental toxicology, health risk assessments, susceptible (sub) populations, sanitation and clean water, human biomonitoring, environmental medicine, and public health aspects of exposure-related outcomes.