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Wastewater treatment and public health in Nunavut: a microbial risk assessment framework for the Canadian Arctic

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Wastewater management in Canadian Arctic communities is influenced by several geographical factors including climate, remoteness, population size, and local food-harvesting practices. Most communities use trucked collection services and basic treatment systems, which are capable of only low-level pathogen removal. These systems are typically reliant solely on natural environmental processes for treatment and make use of existing lagoons, wetlands, and bays. They are operated in a manner such that partially treated wastewater still containing potentially hazardous microorganisms is released into the terrestrial and aquatic environment at random times. Northern communities rely heavily on their local surroundings as a source of food, drinking water, and recreation, thus creating the possibility of human exposure to wastewater effluent. Human exposure to microbial hazards present in municipal wastewater can lead to acute gastrointestinal illness or more severe disease. Although estimating the actual disease burdens associated with wastewater exposures in Arctic communities is challenging, waterborne- and sanitation-related illness is believed to be comparatively higher than in other parts of Canada. This review offers a conceptual framework and evaluation of current knowledge to enable the first microbial risk assessment of exposure scenarios associated with food-harvesting and recreational activities in Arctic communities, where simplified wastewater systems are being operated.
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WATER, SANITATION, POLLUTION AND HEALTH IN THE ARCTIC
Wastewater treatment and public health in Nunavut: a microbial
risk assessment framework for the Canadian Arctic
Kiley Daley
1
&Rob Jamieson
2
&Daniel Rainham
3
&Lisbeth Truelstrup Hansen
4
Received: 4 September 2016 /Accepted: 2 February 2017 /Published online: 21 February 2017
#Springer-Verlag Berlin Heidelberg 2017
Abstract Wastewater management in Canadian Arctic com-
munities is influenced by several geographical factors includ-
ing climate, remoteness, population size, and local food-
harvestingpractices. Most communities use trucked collection
services and basic treatment systems, which are capable of
only low-level pathogen removal. These systems are typically
reliant solely on natural environmental processes for treatment
and make use of existing lagoons, wetlands, and bays. They
are operatedin a mannersuch thatpartially treated wastewater
still containing potentially hazardous microorganisms is re-
leased into the terrestrial and aquatic environment at random
times. Northern communities rely heavily on their local sur-
roundings as a source of food, drinking water, and recreation,
thus creating the possibility of human exposure to wastewater
effluent. Human exposure to microbial hazards present in mu-
nicipal wastewater can lead to acute gastrointestinal illness or
more severe disease. Although estimating the actual disease
burdens associated with wastewater exposures in Arctic com-
munities is challenging, waterborne- and sanitation-related ill-
ness is believed to be comparatively higher than in other parts
of Canada. This review offers a conceptual framework and
evaluation of current knowledge to enable the first microbial
risk assessment of exposure scenarios associated with food-
harvesting and recreational activities in Arctic communities,
where simplified wastewater systems are being operated.
Keywords Conceptual model .Environmental exposures .
Indigenous health .Inuit .Quantitative microbial risk
assessment (QMRA) .Rural health .Water, Sanitation, and
Hygiene (WASH) .Wastewater
Introduction
Communities in the Canadian Arctic territory of Nunavut face
unique wastewater treatment challenges due to climate, re-
moteness, small populations, and local food-harvesting prac-
tices (Bjerregaard et al. 2008; Johnson et al. 2014; Lam and
Livingston 2011;Martinetal.2007). The territory has a total
population of 34,000 spread across 25 remote communities,
varying in population from 150 to 7000 (Nunavut Bureau of
Statistics 2014). No roads connect the 25 isolated communi-
ties to one another or to other communities in Southern
Canada. Thus, each community requires its own municipal
public work infrastructure including wastewater treatment fa-
cilities. All but three have trucked drinking water distribution
and wastewater collection services, as opposed to piped con-
veyance or individual on-site systems. Communities use basic
wastewater treatment systems that are capable of only low
levels of pathogen removal (Huang et al. 2014). These sys-
tems typically rely exclusively on natural environmental pro-
cesses for treatment, making use of existing lagoons, wet-
lands, and ocean bays. They are operated in a manner such
that effluentpartially treated wastewater still containing po-
tentially hazardous microorganismsis released into the ter-
restrial and aquatic environment at random times.
Responsible editor: Gerald Thouand
*Kiley Daley
kiley.daley@dal.ca
1
Centre for Water Resources Studies, Dalhousie University,
Halifax, NS, Canada
2
Department of Process Engineering and Applied Science, Dalhousie
University, Halifax, NS, Canada
3
Environmental Science Program, Dalhousie University, Halifax, NS,
Canada
4
National Food Institute, Technical University of Denmark, Kongens
Lyngby, Denmark
Environ Sci Pollut Res (2018) 25:3286032872
DOI 10.1007/s11356-017-8566-8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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