In recent years there has been a trend to view the Citizens’ Observatory as an increasingly
esse... more In recent years there has been a trend to view the Citizens’ Observatory as an increasingly
essential tool that provides an approach for better observing, understanding, protecting and
enhancing our environment. However, there is no consensus on how to develop such a
system, nor is there any agreement on what a Citizens’ Observatory is and what results it
could produce. The increase in the prevalence of Citizens’ Observatories globally has been
mirrored by an increase in the number of variables that are monitored, the number of
monitoring locations and the types of participating citizens. This calls for a more integrated
approach to handle the emerging complexities involved in this field, but before this can be
achieved, it is essential to establish a common foundation for Citizens’ Observatories and
their usage. There are many aspects to a Citizens’ Observatory. One view is that its essence is
a process that involves environmental monitoring, information gathering, data management
and analysis, assessment and reporting systems. Hence, it requires the development of novel
monitoring technologies and of advanced data management strategies to capture, analyse and
survey the data, thus facilitating their exploitation for policy and society. Practically, there are
many challenges in implementing the Citizens’ Observatory approach, such as ensuring
effective citizens’ participation, dealing with data privacy, accounting for ethical and security
requirements, and taking into account data standards, quality and reliability. These concerns
all need to be addressed in a concerted way to provide a stable, reliable and scalable Citizens’
Observatory programme. On the other hand, the Citizens’ Observatory approach carries the
promise of increasing the public’s awareness to risks in their environment, which has a
corollary economic value, and enhancing data acquisition at low or no cost. In this paper, we first propose a conceptual framework for a Citizens’ Observatory programme as a system that
supports and promotes community-based environmental governance. Next, we discuss some
of the challenges involved in developing this approach. This work seeks to initiate a debate
and help defining what is the Citizens’ Observatory, its potential role in environmental
governance, and its validity as a tool for environmental research.
Chronic environmental exposure to particulate matter &amp... more Chronic environmental exposure to particulate matter <2.5μm in diameter (PM2.5) has been associated with cardiovascular disease; however, the effect of air pollution on myocardial infarction (MI) survivors is not clear. We studied the association of chronic exposure to PM2.5 with death and recurrent cardiovascular events in MI survivors. Consecutive patients aged ≤65years admitted to all medical centers in central Israel after first-MI in 1992-1993 were followed through 2005 for cardiovascular events and 2011 for survival. Data on sociodemographic and prognostic factors were collected at baseline and during follow-up. Residential exposure to PM2.5 was estimated for each patient based on data recorded at air quality monitoring stations. Cox and Andersen-Gill proportional hazards models were used to study the pollution-outcome association. Among the 1120 patients, 469 (41.9%) died and 541 (48.3%) experienced one or more recurrent cardiovascular event. The adjusted hazard ratios associated with a 10μg/m(3) increase in PM2.5 exposure were 1.3 (95% CI 0.8-2.1) for death and 1.5 (95% CI 1.1-1.9) for multiple recurrences of cardiovascular events (MI, heart failure and stroke). When adjustment for socio-demographic factors is performed, cumulative chronic exposure to PM2.5 is positively associated with recurrence of cardiovascular events in patients after a first MI.
Frailty, a multidimensional syndrome of increased vulnerability, is prevalent post-myocardial inf... more Frailty, a multidimensional syndrome of increased vulnerability, is prevalent post-myocardial infarction (MI) and predicts mortality and recurrent events. We investigated whether chronic exposure to particulate matter ≤2.5 μm in diameter (PM2.5) is associated with the development of post-MI frailty. Participants (n = 1120) were aged 65 or less and admitted to hospital in central Israel with first MI in 1992 and 1993. Daily measures of PM2.5 recorded at air quality monitoring stations were summarized and chronic exposure was estimated individually using the geo-coded residential location. Frailty assessment was conducted via an index based on deficit accumulation, and those defined as frail (applying a threshold of ≥0.25) at baseline were excluded. Remaining participants who survived to follow-up 10 to 13 years post-MI (n = 848) were reassessed for frailty. Logistic regression models were constructed to evaluate the role of PM2.5 exposure in frailty risk prediction. Mean exposure to PM2.5 was 24.2 μg/m(3) (range, 16.9-28.6). A total of 301 participants (35.5%) developed frailty during follow-up. Adjusting for sociodemographic and clinical variables, PM2.5 exposure was associated with increased odds of developing frailty (odds ratio, 1.53; 95% confidence interval, 1.22-1.91, comparing the 75th vs. 25th percentiles). Addition of PM2.5 exposure to the multivariable model resulted in an integrated discrimination improvement of 1.60% (P = .005) and a net reclassification index of 6.51% (P = .02). An association was observed between exposure to PM2.5 and incidence of frailty, providing a potential intermediary between air pollution and post-MI outcomes.
The dry deposition algorithms of AERMOD and CALPUFF were compared, studying emissions from hypoth... more The dry deposition algorithms of AERMOD and CALPUFF were compared, studying emissions from hypothetical area and point sources in flat terrain. The deposited fractions calculated by AERMOD and CALPUFF are different for the C, D and F stability classes. In all the studied scenarios the differences between the deposited fractions calculated by AERMOD and CALPUFF are much smaller than those calculated previously in complex terrain. Yet, the detected differences in the deposited fractions may affect the ambient concentrations calculated by AERMOD and CALPUFF in the receptor points as a part of an environmental impact assessment and lead to different conclusions on the residents' exposure. The distinct account of AERMOD and CALPUFF to certain wind speeds and stability classes, and their different algorithms for calculating the dispersion coefficients, is the only explanation for the different estimates of deposited fractions between AERMOD and CALPUFF over absolutely flat terrain.
To date, phosphate surface mining suffers from lack of reliable emission factors. Due to complete... more To date, phosphate surface mining suffers from lack of reliable emission factors. Due to complete absence of data to derive emissions factors, we developed a methodology for estimating them indirectly by studying a range of possible emission factors for surface phosphate mining operations and comparing AERMOD calculated concentrations to concentrations measured around the mine. We applied this approach for the Khneifiss phosphate mine, Syria, and the Al-Hassa and Al-Abyad phosphate mines, Jordan. The work accounts for numerous model unknowns and parameter uncertainties by applying prudent assumptions concerning the parameter values. Our results suggest that the net mining operations (bulldozing, grading and dragline) contribute rather little to ambient TSP concentrations in comparison to phosphate processing and transport. Based on our results, the common practice of deriving the emission rates for phosphate mining operations from the US EPA emission factors for surface coal mining or from the default emission factor of the EEA seems to be reasonable. Yet, since multiple factors affect dispersion from surface phosphate mines, a range of emission factors, rather than only a single value, was found to satisfy the model performance.
This study investigates the association between exposure to ambient NOx and SO2 originating from ... more This study investigates the association between exposure to ambient NOx and SO2 originating from power plant emissions and prevalence of obstructive pulmonary disease and related symptoms. The Orot Rabin coal-fired power plant is the largest power generating facility in the Eastern Mediterranean. Two novel methods assessing exposure to power plant-specific emissions were estimated for 2244 participants who completed the European Community Respiratory Health Survey. The "source approach" modeled emissions traced back to the power plant while the "event approach" identified peak exposures from power plant plume events. Respiratory symptoms, but not prevalence of asthma and COPD, were associated with estimates of power plant NOx emissions. The "source approach" yielded a better estimate of exposure to power plant emissions and showed a stronger dose-response relationship with outcomes. Calculating the portion of ambient pollution attributed to power plants emissions can be useful for air quality management purposes and targeted abatement programs.
A new similarity solution for spray distribution in a boundary layer flow, involving an imaginary... more A new similarity solution for spray distribution in a boundary layer flow, involving an imaginary-valued variable, is presented. The flow field similarity solution has three branches, the two known solutions for accelerating flow and moderately decelerating flow ...
This study evaluates AERMOD and CALPUFF dispersion calculations of particulate matter emissions f... more This study evaluates AERMOD and CALPUFF dispersion calculations of particulate matter emissions from stone quarries in two mountainous regions against TSP and PM10 measurements, using both observational and WRF-modeled meteorological data. Due to different model parameterization, AERMOD dispersion predictions were in better agreement with the measured concentrations than those obtained by CALPUFF. As expected, the smaller the distance between the meteorological station, the source (quarry) and the receptors, the better the predictions of both AERMOD and CALPUFF. In contrast, using in-situ wind field obtained by runs of the WRF meteorological model for the complex terrain study area provided, in general, less accurate dispersion estimates than when using (even remote) meteorological observations. In particular, using the three-dimensional WRF-modeled wind field within CALPUFF did not provide any advantage over using the two-dimensional wind field, which is the common procedure of AERMOD and CALPUFF. Dry deposition was more significant for ambient concentration estimation in AERMOD than in CALPUFF.
Background: The impact of SO2 and NO2 on population health is growing, due to increasing industri... more Background: The impact of SO2 and NO2 on population health is growing, due to increasing industrialization. Objective: To measure the effects of ambient SO2 and NO2 on cardiac and respiratory emergency department (ED) patient load. Methods: Half-hourly values for NO2 and SO2 concentration, temperature, precipitation, and wind direction from 18 regional monitoring stations between January 2000 and December 2006, were pooled by consecutive 12-hour periods. Outcome data, based on ICD-9 codes, included acute cardiac and respiratory admissions to a regional ED. Cases and controls were periods with the highest and lowest ED patient volumes, respectively. For each 12-hour period, pollutant concentrations were introduced as independent exposure variables. Measurements during case and control periods were compared using logistic modeling to estimate the effects of pollutants on the risk of high-volume ED periods, adjusting for additional air quality parameters. Poisson regression addressed t...
In recent years there has been a trend to view the Citizens’ Observatory as an increasingly
esse... more In recent years there has been a trend to view the Citizens’ Observatory as an increasingly
essential tool that provides an approach for better observing, understanding, protecting and
enhancing our environment. However, there is no consensus on how to develop such a
system, nor is there any agreement on what a Citizens’ Observatory is and what results it
could produce. The increase in the prevalence of Citizens’ Observatories globally has been
mirrored by an increase in the number of variables that are monitored, the number of
monitoring locations and the types of participating citizens. This calls for a more integrated
approach to handle the emerging complexities involved in this field, but before this can be
achieved, it is essential to establish a common foundation for Citizens’ Observatories and
their usage. There are many aspects to a Citizens’ Observatory. One view is that its essence is
a process that involves environmental monitoring, information gathering, data management
and analysis, assessment and reporting systems. Hence, it requires the development of novel
monitoring technologies and of advanced data management strategies to capture, analyse and
survey the data, thus facilitating their exploitation for policy and society. Practically, there are
many challenges in implementing the Citizens’ Observatory approach, such as ensuring
effective citizens’ participation, dealing with data privacy, accounting for ethical and security
requirements, and taking into account data standards, quality and reliability. These concerns
all need to be addressed in a concerted way to provide a stable, reliable and scalable Citizens’
Observatory programme. On the other hand, the Citizens’ Observatory approach carries the
promise of increasing the public’s awareness to risks in their environment, which has a
corollary economic value, and enhancing data acquisition at low or no cost. In this paper, we first propose a conceptual framework for a Citizens’ Observatory programme as a system that
supports and promotes community-based environmental governance. Next, we discuss some
of the challenges involved in developing this approach. This work seeks to initiate a debate
and help defining what is the Citizens’ Observatory, its potential role in environmental
governance, and its validity as a tool for environmental research.
Chronic environmental exposure to particulate matter &amp... more Chronic environmental exposure to particulate matter <2.5μm in diameter (PM2.5) has been associated with cardiovascular disease; however, the effect of air pollution on myocardial infarction (MI) survivors is not clear. We studied the association of chronic exposure to PM2.5 with death and recurrent cardiovascular events in MI survivors. Consecutive patients aged ≤65years admitted to all medical centers in central Israel after first-MI in 1992-1993 were followed through 2005 for cardiovascular events and 2011 for survival. Data on sociodemographic and prognostic factors were collected at baseline and during follow-up. Residential exposure to PM2.5 was estimated for each patient based on data recorded at air quality monitoring stations. Cox and Andersen-Gill proportional hazards models were used to study the pollution-outcome association. Among the 1120 patients, 469 (41.9%) died and 541 (48.3%) experienced one or more recurrent cardiovascular event. The adjusted hazard ratios associated with a 10μg/m(3) increase in PM2.5 exposure were 1.3 (95% CI 0.8-2.1) for death and 1.5 (95% CI 1.1-1.9) for multiple recurrences of cardiovascular events (MI, heart failure and stroke). When adjustment for socio-demographic factors is performed, cumulative chronic exposure to PM2.5 is positively associated with recurrence of cardiovascular events in patients after a first MI.
Frailty, a multidimensional syndrome of increased vulnerability, is prevalent post-myocardial inf... more Frailty, a multidimensional syndrome of increased vulnerability, is prevalent post-myocardial infarction (MI) and predicts mortality and recurrent events. We investigated whether chronic exposure to particulate matter ≤2.5 μm in diameter (PM2.5) is associated with the development of post-MI frailty. Participants (n = 1120) were aged 65 or less and admitted to hospital in central Israel with first MI in 1992 and 1993. Daily measures of PM2.5 recorded at air quality monitoring stations were summarized and chronic exposure was estimated individually using the geo-coded residential location. Frailty assessment was conducted via an index based on deficit accumulation, and those defined as frail (applying a threshold of ≥0.25) at baseline were excluded. Remaining participants who survived to follow-up 10 to 13 years post-MI (n = 848) were reassessed for frailty. Logistic regression models were constructed to evaluate the role of PM2.5 exposure in frailty risk prediction. Mean exposure to PM2.5 was 24.2 μg/m(3) (range, 16.9-28.6). A total of 301 participants (35.5%) developed frailty during follow-up. Adjusting for sociodemographic and clinical variables, PM2.5 exposure was associated with increased odds of developing frailty (odds ratio, 1.53; 95% confidence interval, 1.22-1.91, comparing the 75th vs. 25th percentiles). Addition of PM2.5 exposure to the multivariable model resulted in an integrated discrimination improvement of 1.60% (P = .005) and a net reclassification index of 6.51% (P = .02). An association was observed between exposure to PM2.5 and incidence of frailty, providing a potential intermediary between air pollution and post-MI outcomes.
The dry deposition algorithms of AERMOD and CALPUFF were compared, studying emissions from hypoth... more The dry deposition algorithms of AERMOD and CALPUFF were compared, studying emissions from hypothetical area and point sources in flat terrain. The deposited fractions calculated by AERMOD and CALPUFF are different for the C, D and F stability classes. In all the studied scenarios the differences between the deposited fractions calculated by AERMOD and CALPUFF are much smaller than those calculated previously in complex terrain. Yet, the detected differences in the deposited fractions may affect the ambient concentrations calculated by AERMOD and CALPUFF in the receptor points as a part of an environmental impact assessment and lead to different conclusions on the residents' exposure. The distinct account of AERMOD and CALPUFF to certain wind speeds and stability classes, and their different algorithms for calculating the dispersion coefficients, is the only explanation for the different estimates of deposited fractions between AERMOD and CALPUFF over absolutely flat terrain.
To date, phosphate surface mining suffers from lack of reliable emission factors. Due to complete... more To date, phosphate surface mining suffers from lack of reliable emission factors. Due to complete absence of data to derive emissions factors, we developed a methodology for estimating them indirectly by studying a range of possible emission factors for surface phosphate mining operations and comparing AERMOD calculated concentrations to concentrations measured around the mine. We applied this approach for the Khneifiss phosphate mine, Syria, and the Al-Hassa and Al-Abyad phosphate mines, Jordan. The work accounts for numerous model unknowns and parameter uncertainties by applying prudent assumptions concerning the parameter values. Our results suggest that the net mining operations (bulldozing, grading and dragline) contribute rather little to ambient TSP concentrations in comparison to phosphate processing and transport. Based on our results, the common practice of deriving the emission rates for phosphate mining operations from the US EPA emission factors for surface coal mining or from the default emission factor of the EEA seems to be reasonable. Yet, since multiple factors affect dispersion from surface phosphate mines, a range of emission factors, rather than only a single value, was found to satisfy the model performance.
This study investigates the association between exposure to ambient NOx and SO2 originating from ... more This study investigates the association between exposure to ambient NOx and SO2 originating from power plant emissions and prevalence of obstructive pulmonary disease and related symptoms. The Orot Rabin coal-fired power plant is the largest power generating facility in the Eastern Mediterranean. Two novel methods assessing exposure to power plant-specific emissions were estimated for 2244 participants who completed the European Community Respiratory Health Survey. The "source approach" modeled emissions traced back to the power plant while the "event approach" identified peak exposures from power plant plume events. Respiratory symptoms, but not prevalence of asthma and COPD, were associated with estimates of power plant NOx emissions. The "source approach" yielded a better estimate of exposure to power plant emissions and showed a stronger dose-response relationship with outcomes. Calculating the portion of ambient pollution attributed to power plants emissions can be useful for air quality management purposes and targeted abatement programs.
A new similarity solution for spray distribution in a boundary layer flow, involving an imaginary... more A new similarity solution for spray distribution in a boundary layer flow, involving an imaginary-valued variable, is presented. The flow field similarity solution has three branches, the two known solutions for accelerating flow and moderately decelerating flow ...
This study evaluates AERMOD and CALPUFF dispersion calculations of particulate matter emissions f... more This study evaluates AERMOD and CALPUFF dispersion calculations of particulate matter emissions from stone quarries in two mountainous regions against TSP and PM10 measurements, using both observational and WRF-modeled meteorological data. Due to different model parameterization, AERMOD dispersion predictions were in better agreement with the measured concentrations than those obtained by CALPUFF. As expected, the smaller the distance between the meteorological station, the source (quarry) and the receptors, the better the predictions of both AERMOD and CALPUFF. In contrast, using in-situ wind field obtained by runs of the WRF meteorological model for the complex terrain study area provided, in general, less accurate dispersion estimates than when using (even remote) meteorological observations. In particular, using the three-dimensional WRF-modeled wind field within CALPUFF did not provide any advantage over using the two-dimensional wind field, which is the common procedure of AERMOD and CALPUFF. Dry deposition was more significant for ambient concentration estimation in AERMOD than in CALPUFF.
Background: The impact of SO2 and NO2 on population health is growing, due to increasing industri... more Background: The impact of SO2 and NO2 on population health is growing, due to increasing industrialization. Objective: To measure the effects of ambient SO2 and NO2 on cardiac and respiratory emergency department (ED) patient load. Methods: Half-hourly values for NO2 and SO2 concentration, temperature, precipitation, and wind direction from 18 regional monitoring stations between January 2000 and December 2006, were pooled by consecutive 12-hour periods. Outcome data, based on ICD-9 codes, included acute cardiac and respiratory admissions to a regional ED. Cases and controls were periods with the highest and lowest ED patient volumes, respectively. For each 12-hour period, pollutant concentrations were introduced as independent exposure variables. Measurements during case and control periods were compared using logistic modeling to estimate the effects of pollutants on the risk of high-volume ED periods, adjusting for additional air quality parameters. Poisson regression addressed t...
Uploads
Papers by David Broday
essential tool that provides an approach for better observing, understanding, protecting and
enhancing our environment. However, there is no consensus on how to develop such a
system, nor is there any agreement on what a Citizens’ Observatory is and what results it
could produce. The increase in the prevalence of Citizens’ Observatories globally has been
mirrored by an increase in the number of variables that are monitored, the number of
monitoring locations and the types of participating citizens. This calls for a more integrated
approach to handle the emerging complexities involved in this field, but before this can be
achieved, it is essential to establish a common foundation for Citizens’ Observatories and
their usage. There are many aspects to a Citizens’ Observatory. One view is that its essence is
a process that involves environmental monitoring, information gathering, data management
and analysis, assessment and reporting systems. Hence, it requires the development of novel
monitoring technologies and of advanced data management strategies to capture, analyse and
survey the data, thus facilitating their exploitation for policy and society. Practically, there are
many challenges in implementing the Citizens’ Observatory approach, such as ensuring
effective citizens’ participation, dealing with data privacy, accounting for ethical and security
requirements, and taking into account data standards, quality and reliability. These concerns
all need to be addressed in a concerted way to provide a stable, reliable and scalable Citizens’
Observatory programme. On the other hand, the Citizens’ Observatory approach carries the
promise of increasing the public’s awareness to risks in their environment, which has a
corollary economic value, and enhancing data acquisition at low or no cost. In this paper, we first propose a conceptual framework for a Citizens’ Observatory programme as a system that
supports and promotes community-based environmental governance. Next, we discuss some
of the challenges involved in developing this approach. This work seeks to initiate a debate
and help defining what is the Citizens’ Observatory, its potential role in environmental
governance, and its validity as a tool for environmental research.
essential tool that provides an approach for better observing, understanding, protecting and
enhancing our environment. However, there is no consensus on how to develop such a
system, nor is there any agreement on what a Citizens’ Observatory is and what results it
could produce. The increase in the prevalence of Citizens’ Observatories globally has been
mirrored by an increase in the number of variables that are monitored, the number of
monitoring locations and the types of participating citizens. This calls for a more integrated
approach to handle the emerging complexities involved in this field, but before this can be
achieved, it is essential to establish a common foundation for Citizens’ Observatories and
their usage. There are many aspects to a Citizens’ Observatory. One view is that its essence is
a process that involves environmental monitoring, information gathering, data management
and analysis, assessment and reporting systems. Hence, it requires the development of novel
monitoring technologies and of advanced data management strategies to capture, analyse and
survey the data, thus facilitating their exploitation for policy and society. Practically, there are
many challenges in implementing the Citizens’ Observatory approach, such as ensuring
effective citizens’ participation, dealing with data privacy, accounting for ethical and security
requirements, and taking into account data standards, quality and reliability. These concerns
all need to be addressed in a concerted way to provide a stable, reliable and scalable Citizens’
Observatory programme. On the other hand, the Citizens’ Observatory approach carries the
promise of increasing the public’s awareness to risks in their environment, which has a
corollary economic value, and enhancing data acquisition at low or no cost. In this paper, we first propose a conceptual framework for a Citizens’ Observatory programme as a system that
supports and promotes community-based environmental governance. Next, we discuss some
of the challenges involved in developing this approach. This work seeks to initiate a debate
and help defining what is the Citizens’ Observatory, its potential role in environmental
governance, and its validity as a tool for environmental research.