title: Human exposure to soil contaminants in subarctic Ontario, Canada.
abstract: BACKGROUND
  Chemical contaminants in the Canadian subarctic present a health risk with exposures primarily occurring via the food consumption.
  
  
  OBJECTIVE
  Characterization of soil contaminants is needed in northern Canada due to increased gardening and agricultural food security initiatives and the presence of known point sources of pollution.
  
  
  METHODS
  A field study was conducted in the western James Bay Region of Ontario, Canada, to examine the concentrations of polychlorinated biphenyls, dichlorodiphenyltrichloroethane and its metabolites (ΣDDT), other organochlorines, and metals/metalloids in potentially contaminated agriculture sites.
  
  
  METHODS
  Exposure pathways were assessed by comparing the estimated daily intake to acceptable daily intake values. Ninety soil samples were collected at random (grid sampling) from 3 plots (A, B, and C) in Fort Albany (on the mainland), subarctic Ontario, Canada. The contaminated-soil samples were analysed by gas chromatography with an electron capture detector or inductively coupled plasma mass spectrometer.
  
  
  RESULTS
  The range of ΣDDT in 90 soil samples was below the limit of detection to 4.19 mg/kg. From the 3 soil plots analysed, Plot A had the highest ΣDDT mean concentration of 1.12 mg/kg, followed by Plot B and Plot C which had 0.09 and 0.01 mg/kg, respectively. Concentrations of other organic contaminants and metals in the soil samples were below the limit of detection or found in low concentrations in all plots and did not present a human health risk.
  
  
  CONCLUSIONS
  Exposure analyses showed that the human risk was below regulatory thresholds. However, the ΣDDT concentration in Plot A exceeded soil guidelines set out by the Canadian Council of Ministers of the Environment of 0.7 mg/kg, and thus the land should not be used for agricultural or recreational purposes. Both Plots B and C were below threshold limits, and this land can be used for agricultural purposes.
authors.affiliation: School of Occupational and Public Health, Ryerson University, Toronto, Ontario, Canada.|School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Ellen Stephanie
authors.initials: ES
authors.lastname: Reyes
authors.affiliation: School of Occupational and Public Health, Ryerson University, Toronto, Ontario, Canada; eric.liberda@ryerson.ca.
authors.forename: Eric Nicholas
authors.initials: EN
authors.lastname: Liberda
authors.affiliation: Health Studies and Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada.
authors.forename: Leonard James S
authors.initials: LJ
authors.lastname: Tsuji
mesh_terms: D001110:Arctic Regions; D002170:Canada; D004784:Environmental Monitoring / Q000379:methods; D004787:Environmental Pollution / Q000009:adverse effects / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis* / Q000706:statistics & numerical data; D006801:Humans; D009864:Ontario; D011078:Polychlorinated Biphenyls / Q000009:adverse effects / Q000032:analysis*; D012015:Reference Standards; D018570:Risk Assessment; D012494:Sampling Studies; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil; D011078:Polychlorinated Biphenyls
keywords: Aboriginal health; DDT; risk assessment; soil; soil ingestion