TY - JOUR
T1 - Variation of Legionella spp. with Lake Depth and Season in Two Norwegian Drinking Water Sources
AU - Meegoda, Charuka S.
AU - Waak, Michael B.
AU - Kim, Taegyu
AU - Hozalski, Raymond M.
AU - Hallé, Cynthia
N1 - Publisher Copyright:
© 2022 The Authors. Published by American Chemical Society.
PY - 2021
Y1 - 2021
N2 - In Norway, placement of the water treatment plant intake within the lake hypolimnion is considered a hygienic barrier against pathogens of fecal origin. It is unclear, however, whether this practice provides a barrier against opportunistic pathogens such as Legionella. In this study, water samples were collected at 10 m depth intervals near the drinking water intakes of two lakes. Legionella and one of their common hosts, Acanthamoeba spp., were quantified using culture-based assays (Legionella pneumophila only) and real-Time quantitative PCR (qPCR). L. pneumophila and Acanthamoeba spp. were never detected by qPCR; Legionella spp., however, were present in all samples at concentrations ranging from 2.33 to 4.14 log10[copies/L] in lake A and from 2.69 to 4.27 log10[copies/L] in lake B. For most sampling months in both lakes, there was no significant difference between total bacteria and Legionella spp. concentrations at the intake depth versus those on the lake surface. The results of this limited investigation of two Norwegian water supplies suggest that placement of water treatment plant intakes within the hypolimnion may not afford a sufficient hygienic barrier against Legionella.
AB - In Norway, placement of the water treatment plant intake within the lake hypolimnion is considered a hygienic barrier against pathogens of fecal origin. It is unclear, however, whether this practice provides a barrier against opportunistic pathogens such as Legionella. In this study, water samples were collected at 10 m depth intervals near the drinking water intakes of two lakes. Legionella and one of their common hosts, Acanthamoeba spp., were quantified using culture-based assays (Legionella pneumophila only) and real-Time quantitative PCR (qPCR). L. pneumophila and Acanthamoeba spp. were never detected by qPCR; Legionella spp., however, were present in all samples at concentrations ranging from 2.33 to 4.14 log10[copies/L] in lake A and from 2.69 to 4.27 log10[copies/L] in lake B. For most sampling months in both lakes, there was no significant difference between total bacteria and Legionella spp. concentrations at the intake depth versus those on the lake surface. The results of this limited investigation of two Norwegian water supplies suggest that placement of water treatment plant intakes within the hypolimnion may not afford a sufficient hygienic barrier against Legionella.
KW - Legionella
KW - amoebas
KW - drinking water sources
KW - hygienic barrier
KW - opportunistic pathogens
KW - thermocline
UR - http://www.scopus.com/inward/record.url?scp=85128998634&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85128998634&partnerID=8YFLogxK
U2 - 10.1021/acsestwater.1c00454
DO - 10.1021/acsestwater.1c00454
M3 - Article
AN - SCOPUS:85128998634
SN - 2690-0637
JO - ACS Environmental Science and Technology Water
JF - ACS Environmental Science and Technology Water
ER -