Hrvatske vode, Vol. 30 No. 119, 2022.
Original scientific paper
Impact of water hardness and heating system execution on the colonisation of warm water systems by Legionella spp.
Anita Rakić
; Nastavni zavod za javno zdravstvo Splitsko-dalmatinske županije, Split, Hrvatska
Nives Štambuk
; Nastavni zavod za javno zdravstvo Splitsko-dalmatinske županije, Split, Hrvatska
Davor Ljubas
; Sveučilište u Zagrebu Fakultet strojarstva i brodogradnje, Zagreb, Hrvatska
Dragica Kelam Perić
; Dom zdravlja Zagreb zapad, Zagreb, Hrvatska
Abstract
The paper presents the monitoring of calcium and magnesium concentrations, as well as the presence of Legionella spp. in 121 warm water samples collectedfrom six facilities (4 hotels and 2 nursing homes) in the Split-Dalmatia County. The research included a survey on technical and technological characteristics of the facilities, providingdata important for the quality of warm water. The research included standard statistical methods and a nonparametric test for determining the connection between the chemical indicators and the presence of Legionella
spp. A statistically significant positive correlation of higher concentrations of Ca and Mg ions dissolved in water with the presence of Legionella spp. was determined. It was further determined that a larger number of samples collected from warm water systems with central water heating (17%)were positive for Legionella spp. in comparison to samples collected from decentralised water heating systems (9%). For this reason, it is justified to assume that, in addition to water composition, the technical and technological execution of preparation systems for consumable warm water affects the presence of Legionella spp. as well.
Keywords
water supply system, biofilm, Legionella spp., water hardness
Hrčak ID:
275771
URI
Publication date:
30.3.2022.
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