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Papers by Monica Danon-Schaffer

Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a sect... more Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a section on “Physicochemical Properties of Persistent Organic Pollutants”, which identified key physicoch ...

The vast majority of products containing PBDE compounds are ultimately disposed of in landfills (... more The vast majority of products containing PBDE compounds are ultimately disposed of in landfills (~80%) and the rest incinerated 1 . It has also been found that sediments in the water surrounding landfill and sewage treatment facilities have ng/g range concentrations of PBDEs 2,3 . At present, there are no reported studies quantifying the distribution of PBDEs in landfill soils and the mechanism of leaching of PBDEs from such sites. In the present study we examine profiles of PBDEs in soil samples collected in impacted sites near three major communities in the Canadian arctic and in background locations. The sites selected were assessed to be impacted by landfill leachate (landfills and dumpsites) and wastewater effluents. The aim was also to identify local sources of PBDEs distinct from long-range atmospheric deposition. Methods Sixteen surface soil samples were collected (depths of 0-20 cm below surface) in the summers of 2004 and 2006. The 3 communities sampled were Iqaluit (IQ), ...

A mass-balance model is being developed to predict the environmental fate of polybrominated diphe... more A mass-balance model is being developed to predict the environmental fate of polybrominated diphenyl ethers (PBDEs) in landfills and other systems where they occur. The model considers changes over time for different congeners and includes inputs (e.g. due to e-wastes and polyurethane foam), transfers between the wastes and soil, water and air, reactions that may alter the relative composition of different congeners, and accumulation over time. Specification of various terms in the model will require experimental measurements, now in progress. The model will produce a set of differential equations to be integrated simultaneously by conventional methods. The model may be extended later, with appropriate inputs, to apply to larger systems such as regions 1 .

A preliminary study is ongoing with Polybrominated Diphenyl Ethers (PBDEs) to investigate how the... more A preliminary study is ongoing with Polybrominated Diphenyl Ethers (PBDEs) to investigate how they are entering and being transferred among landfill leachates, sediments and soils in the Canadian Arctic. The leachability of PBDEs from e-wastes and examination of landfill sites to determine their fate and transport are being investigated. The spatial distribution of PBDE contamination is also being evaluated. The research will help to provide the parameters for a model under development to predict PBDE migration in soil, thereby facilitating best management practices for waste disposal systems.

Environmental Management and Sustainable Development, 2014

Leachates from 27 landfills (e.g. planned disposal area) across southern Canada and 11 dump sites... more Leachates from 27 landfills (e.g. planned disposal area) across southern Canada and 11 dump sites (e.g. unorganized disposal area) in the Canadian North were collected (2006) and analysed (2006-2008) for polybrominated diphenyl ethers (PBDEs). There was wide variability in the results, both in terms of the total PBDE concentrations and in the distribution of congeners. Northern sites tended to have lower concentrations than southern ones, but some northern levels were significant, despite the low population density and lack of industry in the north. The North could potentially act as a sink for PBDE contaminants because many organic compounds get deposited via air or water currents in the North even though they were not manufactured there.

From Sources to Solution, 2013

An investigation was undertaken in soil from the Canadian polar circle [Yellowknife (YELL), Iqalu... more An investigation was undertaken in soil from the Canadian polar circle [Yellowknife (YELL), Iqaluit (IQA), and Cambridge Bay (CAM)]. Twenty four soil samples (YELL = 3, IQA = 15, CAM = 6) were collected with the depths of 0-20 cm below surface. Eighty major PCBs congeners were analyzed and twenty two PCBs were detected. Concentrations of PCBs in IQA were found to be the highest (0.11-1111 ng/g on dry weight basis), following in decreasing order: CAM (0.07-145 ng/g) and YELL (0.4-7.1 ng/g). Contamination profiles of PCB congeners were different between Iqaluit samples, while PCBs congener profiles were similar in Yellowknife and Cambridge Bay areas. The background sample sites were chosen to be representative of clean and undisturbed soils. The large difference in concentrations observed between dumpsites and background soil samples suggest PCB deposition into these dumpsites from materials discarded within. This is yet another evidence to show that previously pristine Polar Regions are increasingly getting contaminated through human activities. PCBs are excellent industrial markers in this forensic investigation.

Science of The Total Environment, 2013

A comprehensive mass balance model is developed to track polybrominated diphenyl ethers (PBDEs). ... more A comprehensive mass balance model is developed to track polybrominated diphenyl ethers (PBDEs). • Landfill samples and laboratory results are used to estimate the model parameters. • An urban landfill system is simulated, for past and future scenarios. • Mass transfer is not rate-limiting. Chemical reaction/degradation rates are found to be rate-limiting. • The model provides qualitative understanding of the influence of key variables.

Science of The Total Environment, 2013

Experiments and analysis were carried out by contacting e-waste with distilled water and leachate... more Experiments and analysis were carried out by contacting e-waste with distilled water and leachate from a major urban landfill. Contacting of crushed e-waste from different eras with leachate in a custom built end-over-end contactor led to appreciable mass transfer of Polybrominated diphenyl ethers (PBDEs) to the aqueous phase. Temperature had limited influence for the limited range (10-25°C) investigated. Lower pH (in the range 4 to 9) generally resulted in higher transfer of PBDEs to the aqueous phase. Exposing e-waste to distilled water in the same contactor led to lower, but still appreciable PBDE analysed concentrations, than for leachate, probably due to dislodgement of fine dust from the surface of the e-waste particles.

Environmental Forensics, 2002

This case study, from the province of British Columbia, is described to illustrate the use of env... more This case study, from the province of British Columbia, is described to illustrate the use of environmental forensic techniques. The study involves acid rock drainage (ARD) from the Britannia Mine, a mine located in southwestern British Columbia, that has been closed for approximately 25 years and discharges between 4 and 40 million litres of ARD, depending on the time of year into nearby Howe Sound every day. The ARD occurs as an oxidation of sulphide mineralization exposed to air and water. The sources of ARD contamination from this site are copper, aluminium, iron, zinc and manganese. Current copper concentrations discharging from the 4100 Portal Level range from 40 to 100 mg/L. Environmental forensic techniques are applied to describe the origin of the contaminant release, the timing of the release, the distribution of the contamination, ®nding the responsible parties and allocating remediation costs for cleanup. Other forensic techniques described include the use of geochemistry to determine contaminant degradation.

Environmental Forensics, 2001

In May 2000 an investigation of a contaminated water distribution system in the town of Walkerton... more In May 2000 an investigation of a contaminated water distribution system in the town of Walkerton, Ontario, was performed by the Bruce-Grey-Owen Sound Health Unit (BGOSHU), with the assistance of Health Canada and the Ontario Ministry of Health and Long-Term Care. The purpose of the investigation was to determine the scope, likely cause and contributing factors of an Escherichia coli 0157 : H7 outbreak. This investigation-represented the ®rst documented outbreak of E. coli 0157 : H7 associated with a treated municipal water supply in Canada and the largest multi-bacterial waterborne outbreak in Canada. The investigation proceeded on an expedited basis to determine the extent of damages to the water supply system. Environmental forensic techniques were incorporated into hydrogeological studies, environmental transport assessment, genetic characterization, and fate and transport of contaminants. The probable sources of bacteria contamination included the use of cast-iron pipes, the thickness and concentration of bio-®lm sediment and mineral, the in®ltration of contaminated surface runo due to heavy rain or¯ooding,¯ow velocity related to the diameter of the pipe, and/or surface water.

Water, Air, and Soil Pollution, 2012

Polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) are both classes of pe... more Polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) are both classes of persistent organic pollutants with potential major health and environmental concerns. Many PBDE-and PFCcontaining products are ultimately discarded in landfills. In samples from 28 landfills and dumpsites across Canada, PBDEs and PFCs were detected in almost all landfill leachate samples, with concentrations up to 1,020 and 21,300 ng/L, respectively. Mean concentrations were 166 ng/L for PBDEs and 2,950 ng/L for PFCs. Landfill leachates from southern Canada generally had greater concentrations of PBDEs and PFCs than those from northern Canada. The dominant compounds were decabromodiphenyl ether (BDE-209) (mean contribution 52 %) for the PBDEs and perfluorohexanoic acid (mean contribution 25 %) for the PFCs. There were strong correlations for some compounds within each contaminant class, such as the major congeners in the penta-BDE commercial mix (BDE-47, BDE-99, and BDE-100). Estimated average ∑PBDE and ∑PFC loadings from an urban landfill to the environment were calculated to be 3.5 and 62 tonnes/year, respectively.

Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a sect... more Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a section on “Physicochemical Properties of Persistent Organic Pollutants”, which identified key physicoch ...

The vast majority of products containing PBDE compounds are ultimately disposed of in landfills (... more The vast majority of products containing PBDE compounds are ultimately disposed of in landfills (~80%) and the rest incinerated 1 . It has also been found that sediments in the water surrounding landfill and sewage treatment facilities have ng/g range concentrations of PBDEs 2,3 . At present, there are no reported studies quantifying the distribution of PBDEs in landfill soils and the mechanism of leaching of PBDEs from such sites. In the present study we examine profiles of PBDEs in soil samples collected in impacted sites near three major communities in the Canadian arctic and in background locations. The sites selected were assessed to be impacted by landfill leachate (landfills and dumpsites) and wastewater effluents. The aim was also to identify local sources of PBDEs distinct from long-range atmospheric deposition. Methods Sixteen surface soil samples were collected (depths of 0-20 cm below surface) in the summers of 2004 and 2006. The 3 communities sampled were Iqaluit (IQ), ...

A mass-balance model is being developed to predict the environmental fate of polybrominated diphe... more A mass-balance model is being developed to predict the environmental fate of polybrominated diphenyl ethers (PBDEs) in landfills and other systems where they occur. The model considers changes over time for different congeners and includes inputs (e.g. due to e-wastes and polyurethane foam), transfers between the wastes and soil, water and air, reactions that may alter the relative composition of different congeners, and accumulation over time. Specification of various terms in the model will require experimental measurements, now in progress. The model will produce a set of differential equations to be integrated simultaneously by conventional methods. The model may be extended later, with appropriate inputs, to apply to larger systems such as regions 1 .

A preliminary study is ongoing with Polybrominated Diphenyl Ethers (PBDEs) to investigate how the... more A preliminary study is ongoing with Polybrominated Diphenyl Ethers (PBDEs) to investigate how they are entering and being transferred among landfill leachates, sediments and soils in the Canadian Arctic. The leachability of PBDEs from e-wastes and examination of landfill sites to determine their fate and transport are being investigated. The spatial distribution of PBDE contamination is also being evaluated. The research will help to provide the parameters for a model under development to predict PBDE migration in soil, thereby facilitating best management practices for waste disposal systems.

Environmental Management and Sustainable Development, 2014

Leachates from 27 landfills (e.g. planned disposal area) across southern Canada and 11 dump sites... more Leachates from 27 landfills (e.g. planned disposal area) across southern Canada and 11 dump sites (e.g. unorganized disposal area) in the Canadian North were collected (2006) and analysed (2006-2008) for polybrominated diphenyl ethers (PBDEs). There was wide variability in the results, both in terms of the total PBDE concentrations and in the distribution of congeners. Northern sites tended to have lower concentrations than southern ones, but some northern levels were significant, despite the low population density and lack of industry in the north. The North could potentially act as a sink for PBDE contaminants because many organic compounds get deposited via air or water currents in the North even though they were not manufactured there.

From Sources to Solution, 2013

An investigation was undertaken in soil from the Canadian polar circle [Yellowknife (YELL), Iqalu... more An investigation was undertaken in soil from the Canadian polar circle [Yellowknife (YELL), Iqaluit (IQA), and Cambridge Bay (CAM)]. Twenty four soil samples (YELL = 3, IQA = 15, CAM = 6) were collected with the depths of 0-20 cm below surface. Eighty major PCBs congeners were analyzed and twenty two PCBs were detected. Concentrations of PCBs in IQA were found to be the highest (0.11-1111 ng/g on dry weight basis), following in decreasing order: CAM (0.07-145 ng/g) and YELL (0.4-7.1 ng/g). Contamination profiles of PCB congeners were different between Iqaluit samples, while PCBs congener profiles were similar in Yellowknife and Cambridge Bay areas. The background sample sites were chosen to be representative of clean and undisturbed soils. The large difference in concentrations observed between dumpsites and background soil samples suggest PCB deposition into these dumpsites from materials discarded within. This is yet another evidence to show that previously pristine Polar Regions are increasingly getting contaminated through human activities. PCBs are excellent industrial markers in this forensic investigation.

Science of The Total Environment, 2013

A comprehensive mass balance model is developed to track polybrominated diphenyl ethers (PBDEs). ... more A comprehensive mass balance model is developed to track polybrominated diphenyl ethers (PBDEs). • Landfill samples and laboratory results are used to estimate the model parameters. • An urban landfill system is simulated, for past and future scenarios. • Mass transfer is not rate-limiting. Chemical reaction/degradation rates are found to be rate-limiting. • The model provides qualitative understanding of the influence of key variables.

Science of The Total Environment, 2013

Experiments and analysis were carried out by contacting e-waste with distilled water and leachate... more Experiments and analysis were carried out by contacting e-waste with distilled water and leachate from a major urban landfill. Contacting of crushed e-waste from different eras with leachate in a custom built end-over-end contactor led to appreciable mass transfer of Polybrominated diphenyl ethers (PBDEs) to the aqueous phase. Temperature had limited influence for the limited range (10-25°C) investigated. Lower pH (in the range 4 to 9) generally resulted in higher transfer of PBDEs to the aqueous phase. Exposing e-waste to distilled water in the same contactor led to lower, but still appreciable PBDE analysed concentrations, than for leachate, probably due to dislodgement of fine dust from the surface of the e-waste particles.

Environmental Forensics, 2002

This case study, from the province of British Columbia, is described to illustrate the use of env... more This case study, from the province of British Columbia, is described to illustrate the use of environmental forensic techniques. The study involves acid rock drainage (ARD) from the Britannia Mine, a mine located in southwestern British Columbia, that has been closed for approximately 25 years and discharges between 4 and 40 million litres of ARD, depending on the time of year into nearby Howe Sound every day. The ARD occurs as an oxidation of sulphide mineralization exposed to air and water. The sources of ARD contamination from this site are copper, aluminium, iron, zinc and manganese. Current copper concentrations discharging from the 4100 Portal Level range from 40 to 100 mg/L. Environmental forensic techniques are applied to describe the origin of the contaminant release, the timing of the release, the distribution of the contamination, ®nding the responsible parties and allocating remediation costs for cleanup. Other forensic techniques described include the use of geochemistry to determine contaminant degradation.

Environmental Forensics, 2001

In May 2000 an investigation of a contaminated water distribution system in the town of Walkerton... more In May 2000 an investigation of a contaminated water distribution system in the town of Walkerton, Ontario, was performed by the Bruce-Grey-Owen Sound Health Unit (BGOSHU), with the assistance of Health Canada and the Ontario Ministry of Health and Long-Term Care. The purpose of the investigation was to determine the scope, likely cause and contributing factors of an Escherichia coli 0157 : H7 outbreak. This investigation-represented the ®rst documented outbreak of E. coli 0157 : H7 associated with a treated municipal water supply in Canada and the largest multi-bacterial waterborne outbreak in Canada. The investigation proceeded on an expedited basis to determine the extent of damages to the water supply system. Environmental forensic techniques were incorporated into hydrogeological studies, environmental transport assessment, genetic characterization, and fate and transport of contaminants. The probable sources of bacteria contamination included the use of cast-iron pipes, the thickness and concentration of bio-®lm sediment and mineral, the in®ltration of contaminated surface runo due to heavy rain or¯ooding,¯ow velocity related to the diameter of the pipe, and/or surface water.

Water, Air, and Soil Pollution, 2012

Polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) are both classes of pe... more Polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) are both classes of persistent organic pollutants with potential major health and environmental concerns. Many PBDE-and PFCcontaining products are ultimately discarded in landfills. In samples from 28 landfills and dumpsites across Canada, PBDEs and PFCs were detected in almost all landfill leachate samples, with concentrations up to 1,020 and 21,300 ng/L, respectively. Mean concentrations were 166 ng/L for PBDEs and 2,950 ng/L for PFCs. Landfill leachates from southern Canada generally had greater concentrations of PBDEs and PFCs than those from northern Canada. The dominant compounds were decabromodiphenyl ether (BDE-209) (mean contribution 52 %) for the PBDEs and perfluorohexanoic acid (mean contribution 25 %) for the PFCs. There were strong correlations for some compounds within each contaminant class, such as the major congeners in the penta-BDE commercial mix (BDE-47, BDE-99, and BDE-100). Estimated average ∑PBDE and ∑PFC loadings from an urban landfill to the environment were calculated to be 3.5 and 62 tonnes/year, respectively.