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Source and Route of Pyrrolizidine Alkaloid Contamination in Tea Samples
Published on: September 28, 2022
Pathogen growth in herbal teas used in clinical settings: a possible source of nosocomial infection?
Christine Wilson1, Markus Dettenkofer, Daniel Jonas
1Institute of Environmental Medicine and Hospital Epidemiology, Freiburg University Hospital, Hugstetterstrasse 55, D-79106 Freiburg, Germany.
Abstract:
In some clinical settings, herbal tea is used in patient care (eg, for oral hygiene). Teabags containing herbal tea were therefore tested with regard to the presence of microbial contamination before and after brewing. In addition, pathogen growth in intentionally contaminated brewed tea was investigated over time. Teabags and brewed tea were highly contaminated (maximum mean values of 1.9 x 10(8) CFU/g raw tea), and it was found that the pathogen load of intentionally contaminated tea increased significantly (by a maximum of 10(5) colony-forming units/mL brewed tea) over time, suggesting a possible risk of patients developing a nosocomial infection when used in patient care.
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