Presence of pathogens and indicator microbes at a non-point source subtropical recreational marine beach.
Swimming in ocean water, including ocean water at beaches not impacted by known point sources of pollution, is an increasing health concern. This study was an initial evaluation of the presence of indicator microbes and pathogens and the association among the indicator microbes, pathogens, and environmental conditions at a subtropical, recreational marine beach in south Florida impacted by non-point sources of pollution. Twelve water and eight sand samples were collected during four sampling events at high or low tide under elevated or reduced solar insolation conditions. The analyses performed included analyses of fecal indicator bacteria (FIB) (fecal coliforms, Escherichia coli, enterococci, and Clostridium perfringens), human-associated microbial source tracking (MST) markers (human polyomaviruses [HPyVs] and Enterococcus faecium esp gene), and pathogens (Vibrio vulnificus, Staphylococcus aureus, enterovirus, norovirus, hepatitis A virus, Cryptosporidium spp., and Giardia spp.). The enterococcus concentrations in water and sand determined by quantitative PCR were greater than the concentrations determined by membrane filtration measurement. The FIB concentrations in water were below the recreational water quality standards for three of the four sampling events, when pathogens and MST markers were also generally undetectable. The FIB levels exceeded regulatory guidelines during one event, and this was accompanied by detection of HPyVs and pathogens, including detection of the autochthonous bacterium V. vulnificus in sand and water, detection of the allochthonous protozoans Giardia spp. in water, and detection of Cryptosporidium spp. in sand samples. The elevated microbial levels were detected at high tide and under low-solar-insolation conditions. Additional sampling should be conducted to further explore the relationships between tidal and solar insolation conditions and between indicator microbes and pathogens in subtropical recreational marine waters impacted by non-point source pollution.
Abdelzaher
Amir M
AM
University of Miami, NSF NIEHS Oceans and Human Health Center, Miami, Florida 331491, USA.
Wright
Mary E
ME
Ortega
Cristina
C
Solo-Gabriele
Helena M
HM
Miller
Gary
G
Elmir
Samir
S
Newman
Xihui
X
Shih
Peter
P
Bonilla
J Alfredo
JA
Bonilla
Tonya D
TD
Palmer
Carol J
CJ
Scott
Troy
T
Lukasik
Jerzy
J
Harwood
Valerie J
VJ
McQuaig
Shannon
S
Sinigalliano
Chris
C
Gidley
Maribeth
M
Plano
Lisa R W
LR
Zhu
Xiaofang
X
Wang
John D
JD
Fleming
Lora E
LE
D000818:Animals; D001419:Bacteria / Q000302:isolation & purification*; D001493:Bathing Beaches / Q000592:standards; D003016:Clostridium perfringens / Q000302:isolation & purification; D003458:Cryptosporidium / Q000302:isolation & purification; D016983:Enterococcus / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000302:isolation & purification; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D005431:Florida; D005618:Fresh Water / Q000382:microbiology; D006801:Humans; D010271:Parasites / Q000302:isolation & purification*; D011120:Polyomavirus / Q000302:isolation & purification; D011998:Recreation; D012623:Seawater / Q000382:microbiology* / Q000469:parasitology / Q000821:virology; D012822:Silicon Dioxide; D014780:Viruses / Q000235:genetics / Q000302:isolation & purification*; D014871:Water Microbiology; D014881:Water Supply
D004785:Environmental Pollutants; D012822:Silicon Dioxide