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Nathalie Bonvallot - One of the best experts on this subject based on the ideXlab platform.
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Chemical-by-chemical and Cumulative Risk Assessment of residential indoor exposure to semivolatile organic compounds in France
Environment International, 2018Co-Authors: Maud Pelletier, Philippe Glorennec, Corinne Mandin, Barbara Le Bot, Olivier Ramalho, Fabien Mercier, Nathalie BonvallotAbstract:Background: The toxic effects of environmental exposure to chemicals are increasingly being studied and confirmed, notably for semivolatile organic compounds (SVOCs). These are found in many products and housing materials, from which they are emitted to indoor air, settled dust and other surfaces.Objectives: The objective of this work is to assess the human health Risk posed by residential indoor exposure to 32 SVOCs, assessed in previous nationwide studies. Methods: A chemical-by-chemical Risk Assessment, using a hazard quotient (HQ) or excess Risk (ER) method, was supplemented by a Cumulative Risk Assessment (CRA). For CRA, a hazard index (HI) method, as well as higher tier approaches using relative potency factors (RPFs) or toxic equivalency factors (TEFs) were used for the following endpoints: neurotoxicity, reproductive toxicity, genotoxicity and immunotoxicity. Results:HQs were above 1 for 50% of French children from birth to 2 years for BDE 47, and for 5% of children for lindane and dibutyl phthalate (DBP). Corresponding hazards are reprotoxic for BDE 47 and DBP, and immunotoxic for lindane. The CRA approach provided additional information of reprotoxic Risks (HI > 1) that may occur for 95% of children and for 5% of the offspring for pregnant women's exposure. The SVOCs contributing most to these Risks were PCB 101 and 118, BDE 47, and DBP. The higher tier CRA approaches showed that exposure to dwellings' SVOC mixtures were of concern for 95% of children for neurotoxic compounds having effects linked with neuronal death. To a lesser extent, effects mediated by the aryl hydrocarbon receptor (AhR) or by a decrease in testosterone levels may concern 5% of children and adults. Lastly, unacceptable immunotoxic Risk related to exposure to 8 indoor PCBs was also observed for 5% of children. Conclusions:In view of uncertainties related to compounds' toxicity for humans, these results justify the implementation of preventive measures, as well as the production of more standardized and comprehensive toxicological data for some compounds.
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Relative toxicity for indoor semi volatile organic compounds based on neuronal death
Toxicology Letters, 2017Co-Authors: Kevin Fournier, Philippe Glorennec, Emmanuel Baumont, Nathalie BonvallotAbstract:BACKGROUND: Semi Volatile Organic Compounds (SVOCs) are contaminants commonly found in dwellings as a result of their use as plasticizers, flame retardants, or pesticides in building materials and consumer products. Many SVOCs are suspected of being neurotoxic, based on mammal experimentation (impairment of locomotor activity, spatial learning/memory or behavioral changes), raising the question of Cumulative Risk Assessment. The aim of this work is to estimate the relative toxicity of such SVOCs, based on neuronal death. METHOD: SVOCs fulfilling the following conditions were included: detection frequency >10% in dwellings, availability of data on effects or mechanism of action for neurotoxicity, and availability of dose-response relationships based on cell viability assays as a proxy of neuronal death. Benchmark concentration values (BMC) were estimated using a Hill model, and compared to assess relative toxicity. RESULTS: Of the 58 SVOCs selected, 28 were suspected of being neurotoxic in mammals, and 21 have been documented as inducing a decrease in cell viability in vitro. 13 have at least one dose-response relationship that can be used to derive a BMC based on a 10% fall in neuronal viability. Based on this in vitro endpoint, PCB-153 appeared to be the most toxic compound, having the lowest BMC10 (0.072μM) and diazinon the least toxic compound, having the highest BMC10 (94.35μM). We showed that experimental designs (in particular choice of cell lines) had a significant influence on BMC calculation. CONCLUSION: For the first time, the relative in vitro toxicity of 13 indoor contaminants belonging to different chemical families has been assessed on the basis of neuronal cell viability. Lack of comparable toxicity datasets limits the number of SVOCs that can be included. More standardized protocols in terms of cell lines, species and exposure duration should be developed with a view to Cumulative Risk Assessment.
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Aggregating exposures & cumulating Risk for semivolatile organic compounds: A review
Environmental Research, 2017Co-Authors: Maud Pelletier, Nathalie Bonvallot, Philippe GlorennecAbstract:Increasingly, health Risk Assessment is addressing multiple pathway exposures to multiple contaminants. We reviewed aggregated exposure and Cumulative Risk approaches for contemporary and ubiquitous semivolatile organic compounds (SVOC). We identified 22 studies aggregating exposure pathways, and 31 cumulating Risk. Exposure aggregation is based on the addition of pathway-specific doses, using kinetic modeling where it exists, and classic external dose equations otherwise. In most cases, exposure is dominated by a single route or source of exposure - mainly the oral pathway - via dietary or non-dietary exposure. Preferential routes and sources of exposure are influenced by SVOC physical-chemical properties such as vapor pressure. The Cumulative Risk approach for contaminants is based on dose addition. Simple sum of hazard quotient (Hazard Index: HI) is the most commonly used Cumulative Risk Assessment approach, while Relative Potency Factor (RPF) appeared to the best suited – although this calls for a level of toxicological information that limits the number of compounds that can be studied simultaneously. Where both were performed, moving from HI to more refined approach produced similar results. In conclusion, both approaches - exposure aggregation and Cumulative Risk - rely on simple assumptions. Nevertheless, they allow uncertainty to be reduced, in comparison with source-by-source or chemical-by-chemical approaches.
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Indoor residential exposure to semivolatile organic compounds in France
Environment International, 2017Co-Authors: Maud Pelletier, Nathalie Bonvallot, Corinne Mandin, Barbara Le Bot, Olivier Ramalho, Fabien Mercier, Olivier Blanchard, Wenjuan Wei, Gaëlle Raffy, Philippe GlorennecAbstract:Multiple chemicals are emitted in residential accommodation. Aggregate Daily Doses (ADD) (ng/kg-bw/d) were estimated for 32 semivolatile organic compounds (SVOCs) of different chemical families that are frequently detected in French dwellings in both air and settled dust. Daily doses were determined using steady-state models for the population, categorized into 11 age groups covering birth to age 30. Three routes of exposure were taken into account: dust ingestion, inhalation (gaseous and particulate phases) and dermal contact with the gaseous phase of air. Contamination levels were preferentially retrieved from large, nationwide representative datasets. A two-dimensional probabilistic approach was used to assess parametric uncertainty and identify the most influential factors. For children aged 2 to 3 years, ADD estimates spanned orders of magnitude, with median values ranging from 8.7 pg/kg-bw/d for 2,2′,3,4,4′-pentabromodiphenylether (BDE 85) to 1.3 μg/kg-bw/d for di-isobutyl phthalate (DiBP). Inhalation, ingestion and dermal pathway contributed at varying levels, and depending on compound, air was the dominant medium for 28 of the 32 compounds (either by inhalation or dermal contact). Indoor exposure estimate variance was mainly driven by indoor contamination variability, and secondarily by uncertainty in physical and chemical parameters. These findings lend support to the call for Cumulative Risk Assessment of indoor SVOCs.
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Multiple exposures to indoor contaminants: Derivation of benchmark doses and relative potency factors based on male reprotoxic effects
Regulatory Toxicology and Pharmacology, 2016Co-Authors: Kevin Fournier, Philippe Glorennec, Cleo Tebby, Florence Zeman, Denis Zmirou-navier, Nathalie BonvallotAbstract:Semi-Volatile Organic Compounds (SVOCs) are commonly present in dwellings and several are suspected of having effects on male reproductive function mediated by an endocrine disruption mode of action. To improve knowledge of the health impact of these compounds, Cumulative toxicity indicators are needed. This work derives Benchmark Doses (BMD) and Relative Potency Factors (RPF) for SVOCs acting on the male reproductive system through the same mode of action. We included SVOCs fulfilling the following conditions: detection frequency (>10%) in French dwellings, availability of data on the mechanism/mode of action for male reproductive toxicity, and availability of comparable dose-response relationships. Of 58 SVOCs selected, 18 induce a decrease in serum testosterone levels. Six have sufficient and comparable data to derive BMDs based on 10 or 50% of the response. The SVOCs inducing the largest decrease in serum testosterone concentration are: for 10%, bisphenol A (BMD10= 7.72E-07 mg/kg bw/d; RPF10= 7033679); for 50%, benzo[a]pyrene (BMD50= 0.030 mg/kg bw/d; RPF50= 1630), and the one inducing the smallest one is benzyl butyl phthalate (RPF10 and RPF50= 0.095). This approach encompasses contaminants from diverse chemical families acting through similar modes of action, and makes possible a Cumulative Risk Assessment in indoor environments. The main limitation remains the lack of comparable toxicological data.
Philippe Glorennec - One of the best experts on this subject based on the ideXlab platform.
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Chemical-by-chemical and Cumulative Risk Assessment of residential indoor exposure to semivolatile organic compounds in France
Environment International, 2018Co-Authors: Maud Pelletier, Philippe Glorennec, Corinne Mandin, Barbara Le Bot, Olivier Ramalho, Fabien Mercier, Nathalie BonvallotAbstract:Background: The toxic effects of environmental exposure to chemicals are increasingly being studied and confirmed, notably for semivolatile organic compounds (SVOCs). These are found in many products and housing materials, from which they are emitted to indoor air, settled dust and other surfaces.Objectives: The objective of this work is to assess the human health Risk posed by residential indoor exposure to 32 SVOCs, assessed in previous nationwide studies. Methods: A chemical-by-chemical Risk Assessment, using a hazard quotient (HQ) or excess Risk (ER) method, was supplemented by a Cumulative Risk Assessment (CRA). For CRA, a hazard index (HI) method, as well as higher tier approaches using relative potency factors (RPFs) or toxic equivalency factors (TEFs) were used for the following endpoints: neurotoxicity, reproductive toxicity, genotoxicity and immunotoxicity. Results:HQs were above 1 for 50% of French children from birth to 2 years for BDE 47, and for 5% of children for lindane and dibutyl phthalate (DBP). Corresponding hazards are reprotoxic for BDE 47 and DBP, and immunotoxic for lindane. The CRA approach provided additional information of reprotoxic Risks (HI > 1) that may occur for 95% of children and for 5% of the offspring for pregnant women's exposure. The SVOCs contributing most to these Risks were PCB 101 and 118, BDE 47, and DBP. The higher tier CRA approaches showed that exposure to dwellings' SVOC mixtures were of concern for 95% of children for neurotoxic compounds having effects linked with neuronal death. To a lesser extent, effects mediated by the aryl hydrocarbon receptor (AhR) or by a decrease in testosterone levels may concern 5% of children and adults. Lastly, unacceptable immunotoxic Risk related to exposure to 8 indoor PCBs was also observed for 5% of children. Conclusions:In view of uncertainties related to compounds' toxicity for humans, these results justify the implementation of preventive measures, as well as the production of more standardized and comprehensive toxicological data for some compounds.
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Relative toxicity for indoor semi volatile organic compounds based on neuronal death
Toxicology Letters, 2017Co-Authors: Kevin Fournier, Philippe Glorennec, Emmanuel Baumont, Nathalie BonvallotAbstract:BACKGROUND: Semi Volatile Organic Compounds (SVOCs) are contaminants commonly found in dwellings as a result of their use as plasticizers, flame retardants, or pesticides in building materials and consumer products. Many SVOCs are suspected of being neurotoxic, based on mammal experimentation (impairment of locomotor activity, spatial learning/memory or behavioral changes), raising the question of Cumulative Risk Assessment. The aim of this work is to estimate the relative toxicity of such SVOCs, based on neuronal death. METHOD: SVOCs fulfilling the following conditions were included: detection frequency >10% in dwellings, availability of data on effects or mechanism of action for neurotoxicity, and availability of dose-response relationships based on cell viability assays as a proxy of neuronal death. Benchmark concentration values (BMC) were estimated using a Hill model, and compared to assess relative toxicity. RESULTS: Of the 58 SVOCs selected, 28 were suspected of being neurotoxic in mammals, and 21 have been documented as inducing a decrease in cell viability in vitro. 13 have at least one dose-response relationship that can be used to derive a BMC based on a 10% fall in neuronal viability. Based on this in vitro endpoint, PCB-153 appeared to be the most toxic compound, having the lowest BMC10 (0.072μM) and diazinon the least toxic compound, having the highest BMC10 (94.35μM). We showed that experimental designs (in particular choice of cell lines) had a significant influence on BMC calculation. CONCLUSION: For the first time, the relative in vitro toxicity of 13 indoor contaminants belonging to different chemical families has been assessed on the basis of neuronal cell viability. Lack of comparable toxicity datasets limits the number of SVOCs that can be included. More standardized protocols in terms of cell lines, species and exposure duration should be developed with a view to Cumulative Risk Assessment.
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Aggregating exposures & cumulating Risk for semivolatile organic compounds: A review
Environmental Research, 2017Co-Authors: Maud Pelletier, Nathalie Bonvallot, Philippe GlorennecAbstract:Increasingly, health Risk Assessment is addressing multiple pathway exposures to multiple contaminants. We reviewed aggregated exposure and Cumulative Risk approaches for contemporary and ubiquitous semivolatile organic compounds (SVOC). We identified 22 studies aggregating exposure pathways, and 31 cumulating Risk. Exposure aggregation is based on the addition of pathway-specific doses, using kinetic modeling where it exists, and classic external dose equations otherwise. In most cases, exposure is dominated by a single route or source of exposure - mainly the oral pathway - via dietary or non-dietary exposure. Preferential routes and sources of exposure are influenced by SVOC physical-chemical properties such as vapor pressure. The Cumulative Risk approach for contaminants is based on dose addition. Simple sum of hazard quotient (Hazard Index: HI) is the most commonly used Cumulative Risk Assessment approach, while Relative Potency Factor (RPF) appeared to the best suited – although this calls for a level of toxicological information that limits the number of compounds that can be studied simultaneously. Where both were performed, moving from HI to more refined approach produced similar results. In conclusion, both approaches - exposure aggregation and Cumulative Risk - rely on simple assumptions. Nevertheless, they allow uncertainty to be reduced, in comparison with source-by-source or chemical-by-chemical approaches.
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Indoor residential exposure to semivolatile organic compounds in France
Environment International, 2017Co-Authors: Maud Pelletier, Nathalie Bonvallot, Corinne Mandin, Barbara Le Bot, Olivier Ramalho, Fabien Mercier, Olivier Blanchard, Wenjuan Wei, Gaëlle Raffy, Philippe GlorennecAbstract:Multiple chemicals are emitted in residential accommodation. Aggregate Daily Doses (ADD) (ng/kg-bw/d) were estimated for 32 semivolatile organic compounds (SVOCs) of different chemical families that are frequently detected in French dwellings in both air and settled dust. Daily doses were determined using steady-state models for the population, categorized into 11 age groups covering birth to age 30. Three routes of exposure were taken into account: dust ingestion, inhalation (gaseous and particulate phases) and dermal contact with the gaseous phase of air. Contamination levels were preferentially retrieved from large, nationwide representative datasets. A two-dimensional probabilistic approach was used to assess parametric uncertainty and identify the most influential factors. For children aged 2 to 3 years, ADD estimates spanned orders of magnitude, with median values ranging from 8.7 pg/kg-bw/d for 2,2′,3,4,4′-pentabromodiphenylether (BDE 85) to 1.3 μg/kg-bw/d for di-isobutyl phthalate (DiBP). Inhalation, ingestion and dermal pathway contributed at varying levels, and depending on compound, air was the dominant medium for 28 of the 32 compounds (either by inhalation or dermal contact). Indoor exposure estimate variance was mainly driven by indoor contamination variability, and secondarily by uncertainty in physical and chemical parameters. These findings lend support to the call for Cumulative Risk Assessment of indoor SVOCs.
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Multiple exposures to indoor contaminants: Derivation of benchmark doses and relative potency factors based on male reprotoxic effects
Regulatory Toxicology and Pharmacology, 2016Co-Authors: Kevin Fournier, Philippe Glorennec, Cleo Tebby, Florence Zeman, Denis Zmirou-navier, Nathalie BonvallotAbstract:Semi-Volatile Organic Compounds (SVOCs) are commonly present in dwellings and several are suspected of having effects on male reproductive function mediated by an endocrine disruption mode of action. To improve knowledge of the health impact of these compounds, Cumulative toxicity indicators are needed. This work derives Benchmark Doses (BMD) and Relative Potency Factors (RPF) for SVOCs acting on the male reproductive system through the same mode of action. We included SVOCs fulfilling the following conditions: detection frequency (>10%) in French dwellings, availability of data on the mechanism/mode of action for male reproductive toxicity, and availability of comparable dose-response relationships. Of 58 SVOCs selected, 18 induce a decrease in serum testosterone levels. Six have sufficient and comparable data to derive BMDs based on 10 or 50% of the response. The SVOCs inducing the largest decrease in serum testosterone concentration are: for 10%, bisphenol A (BMD10= 7.72E-07 mg/kg bw/d; RPF10= 7033679); for 50%, benzo[a]pyrene (BMD50= 0.030 mg/kg bw/d; RPF50= 1630), and the one inducing the smallest one is benzyl butyl phthalate (RPF10 and RPF50= 0.095). This approach encompasses contaminants from diverse chemical families acting through similar modes of action, and makes possible a Cumulative Risk Assessment in indoor environments. The main limitation remains the lack of comparable toxicological data.
Adam S. Tenforde - One of the best experts on this subject based on the ideXlab platform.
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characterization of Risk quantification differences using female athlete triad Cumulative Risk Assessment and relative energy deficiency in sport clinical Assessment tool
International Journal of Sport Nutrition and Exercise Metabolism, 2019Co-Authors: Adam S. Tenforde, Bryan Holtzman, Allyson L Parziale, Kathryn E AckermanAbstract:This study’s objective was to identify differences in Risk for low energy availability and athletic clearance level by comparing scores on Female Athlete Triad Cumulative Risk Assessment (Triad CRA...
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bone stress injuries in male distance runners higher modified female athlete triad Cumulative Risk Assessment scores predict increased rates of injury
British Journal of Sports Medicine, 2019Co-Authors: Emily Kraus, Aurelia Nattiv, Michelle T Barrack, Kristin L Sainani, Andrea Kussman, Megan Deakinsroche, Sonal Singh, Adam S. Tenforde, Michael FredericsonAbstract:Objectives Bone stress injuries (BSI) are common in runners of both sexes. The purpose of this study was to determine if a modified Female Athlete Triad Cumulative Risk Assessment tool would predict BSI in male distance runners. Methods 156 male runners at two collegiate programmes were studied using mixed retrospective and prospective design for a total of 7 years. Point values were assigned using Risk Assessment categories including low energy availability, low body mass index (BMI), low bone mineral density (BMD) and prior BSI. The outcome was subsequent development of BSI. Statistical models used a mixed effects Poisson regression model with p Results 42/156 runners (27%) sustained 61 BSIs over an average 1.9 years of follow-up. In the baseline Risk factor model, each 1 point increase in prior BSI score was associated with a 57% increased Risk for prospective BSI (p=0.0042) and each 1 point increase in Cumulative Risk score was associated with a 37% increase in prospective BSI Risk (p=0.0079). In the longitudinal model, each 1 point increase in Cumulative Risk score was associated with a 27% increase in prospective BSI Risk (p=0.05). BMI (rate ratio (RR)=1.91, p=0.11) and BMD (RR=1.58, p=0.19) Risk scores were not associated with BSI. Conclusion A modified Cumulative Risk Assessment tool may help identify male runners at elevated Risk for BSI. Identifying Risk factors may guide treatment and prevention strategies.
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association of the female athlete triad Risk Assessment stratification to the development of bone stress injuries in collegiate athletes
American Journal of Sports Medicine, 2017Co-Authors: Adam S. Tenforde, Jennifer L Carlson, Audrey O Chang, Kristin L Sainani, Rebecca Shultz, Phil Cutti, Neville H Golden, Michael FredericsonAbstract:Background:The female athlete triad (referred to as the triad) contributes to adverse health outcomes, including bone stress injuries (BSIs), in female athletes. Guidelines were published in 2014 for clinical management of athletes affected by the triad.Purpose:This study aimed to (1) classify athletes from a collegiate population of 16 sports into low-, moderate-, and high-Risk categories using the Female Athlete Triad Cumulative Risk Assessment score and (2) evaluate the predictive value of the Risk categories for subsequent BSIs.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 323 athletes completed both electronic preparticipation physical examination and dual-energy x-ray absorptiometry scans. Of these, 239 athletes with known oligomenorrhea/amenorrhea status were assigned to a low-, moderate-, or high-Risk category. Chart review was used to identify athletes who sustained a subsequent BSI during collegiate sports participation; the injury required a physician diagnosis and imaging ...
Michael Fredericson - One of the best experts on this subject based on the ideXlab platform.
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bone stress injuries in male distance runners higher modified female athlete triad Cumulative Risk Assessment scores predict increased rates of injury
British Journal of Sports Medicine, 2019Co-Authors: Emily Kraus, Aurelia Nattiv, Michelle T Barrack, Kristin L Sainani, Andrea Kussman, Megan Deakinsroche, Sonal Singh, Adam S. Tenforde, Michael FredericsonAbstract:Objectives Bone stress injuries (BSI) are common in runners of both sexes. The purpose of this study was to determine if a modified Female Athlete Triad Cumulative Risk Assessment tool would predict BSI in male distance runners. Methods 156 male runners at two collegiate programmes were studied using mixed retrospective and prospective design for a total of 7 years. Point values were assigned using Risk Assessment categories including low energy availability, low body mass index (BMI), low bone mineral density (BMD) and prior BSI. The outcome was subsequent development of BSI. Statistical models used a mixed effects Poisson regression model with p Results 42/156 runners (27%) sustained 61 BSIs over an average 1.9 years of follow-up. In the baseline Risk factor model, each 1 point increase in prior BSI score was associated with a 57% increased Risk for prospective BSI (p=0.0042) and each 1 point increase in Cumulative Risk score was associated with a 37% increase in prospective BSI Risk (p=0.0079). In the longitudinal model, each 1 point increase in Cumulative Risk score was associated with a 27% increase in prospective BSI Risk (p=0.05). BMI (rate ratio (RR)=1.91, p=0.11) and BMD (RR=1.58, p=0.19) Risk scores were not associated with BSI. Conclusion A modified Cumulative Risk Assessment tool may help identify male runners at elevated Risk for BSI. Identifying Risk factors may guide treatment and prevention strategies.
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association of the female athlete triad Risk Assessment stratification to the development of bone stress injuries in collegiate athletes
American Journal of Sports Medicine, 2017Co-Authors: Adam S. Tenforde, Jennifer L Carlson, Audrey O Chang, Kristin L Sainani, Rebecca Shultz, Phil Cutti, Neville H Golden, Michael FredericsonAbstract:Background:The female athlete triad (referred to as the triad) contributes to adverse health outcomes, including bone stress injuries (BSIs), in female athletes. Guidelines were published in 2014 for clinical management of athletes affected by the triad.Purpose:This study aimed to (1) classify athletes from a collegiate population of 16 sports into low-, moderate-, and high-Risk categories using the Female Athlete Triad Cumulative Risk Assessment score and (2) evaluate the predictive value of the Risk categories for subsequent BSIs.Study Design:Cohort study; Level of evidence, 3.Methods:A total of 323 athletes completed both electronic preparticipation physical examination and dual-energy x-ray absorptiometry scans. Of these, 239 athletes with known oligomenorrhea/amenorrhea status were assigned to a low-, moderate-, or high-Risk category. Chart review was used to identify athletes who sustained a subsequent BSI during collegiate sports participation; the injury required a physician diagnosis and imaging ...
Ken Sexton - One of the best experts on this subject based on the ideXlab platform.
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Cumulative health Risk Assessment finding new ideas and escaping from the old ones
Human and Ecological Risk Assessment, 2015Co-Authors: Ken SextonAbstract:Cumulative Risk Assessment (CRA) is an emergent tool for organizing and analyzing scientific information to examine, characterize, and possibly quantify adverse health outcomes from combined effects of exposure to diverse environmental factors, including both chemical and nonchemical stressors. This article examines the implementation of effects-based CRA, which emphasizes evaluating health Risks in a defined community or population, as opposed to stressor-based approaches, which focus on determining health Risks for a defined set of stressors. It discusses the concept of vulnerability-based CRA as a potentially useful alternative, reviews the conceptual constructs that underpin CRA, surveys the diversity of methods available for putting effects-based principles into practice, identifies impediments hindering practical applications, and examines ways to make effects-based CRA more feasible.
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Cumulative Risk Assessment an overview of methodological approaches for evaluating combined health effects from exposure to multiple environmental stressors
International Journal of Environmental Research and Public Health, 2012Co-Authors: Ken SextonAbstract:Systematic evaluation of Cumulative health Risks from the combined effects of multiple environmental stressors is becoming a vital component of Risk-based decisions aimed at protecting human populations and communities. This article briefly examines the historical development of Cumulative Risk Assessment as an analytical tool, and discusses current approaches for evaluating Cumulative health effects from exposure to both chemical mixtures and combinations of chemical and nonchemical stressors. A comparison of stressor-based and effects-based Assessment methods is presented, and the potential value of focusing on viable Risk management options to limit the scope of Cumulative evaluations is discussed. The ultimate goal of Cumulative Risk Assessment is to provide answers to decision-relevant questions based on organized scientific analysis; even if the answers, at least for the time being, are inexact and uncertain.
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conceptual models for Cumulative Risk Assessment
American Journal of Public Health, 2011Co-Authors: Stephen H Linder, Ken SextonAbstract:In the absence of scientific consensus on an appropriate theoretical framework, Cumulative Risk Assessment and related research have relied on speculative conceptual models.We argue for the importance of theoretical backing for such models and discuss 3 relevant theoretical frameworks, each supporting a distinctive “family” of models. Social determinant models postulate that unequal health outcomes are caused by structural inequalities; health disparity models envision social and contextual factors acting through individual behaviors and biological mechanisms; and multiple stressor models incorporate environmental agents, emphasizing the intermediary role of these and other stressors.The conclusion is that more careful reliance on established frameworks will lead directly to improvements in characterizing Cumulative Risk burdens and accounting for disproportionate adverse health effects.
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Cumulative Risk Assessment for combined health effects from chemical and nonchemical stressors
American Journal of Public Health, 2011Co-Authors: Ken Sexton, Stephen H LinderAbstract:Cumulative Risk Assessment is a science policy tool for organizing and analyzing information to examine, characterize, and possibly quantify combined threats from multiple environmental stressors. We briefly survey the state of the art regarding Cumulative Risk Assessment, emphasizing challenges and complexities of moving beyond the current focus on chemical mixtures to incorporate nonchemical stressors, such as poverty and discrimination, into the Assessment paradigm. Theoretical frameworks for integrating nonchemical stressors into Cumulative Risk Assessments are discussed, the impact of geospatial issues on interpreting results of statistical analyses is described, and four Assessment methods are used to illustrate the diversity of current approaches. Prospects for future progress depend on adequate research support as well as development and verification of appropriate analytic frameworks.
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the role of Cumulative Risk Assessment in decisions about environmental justice
International Journal of Environmental Research and Public Health, 2010Co-Authors: Ken Sexton, Stephen H LinderAbstract:There is strong presumptive evidence that people living in poverty and certain racial and ethnic groups bear a disproportionate burden of environmental health Risk. Many have argued that conducting formal Assessments of the health Risk experienced by affected communities is both unnecessary and counterproductive—that instead of analyzing the situation our efforts should be devoted to fixing obvious problems and rectifying observable wrongs. We contend that formal Assessment of Cumulative health Risks from combined effects of chemical and nonchemical stressors is a valuable tool to aid decision makers in choosing Risk management options that are effective, efficient, and equitable. If used properly, Cumulative Risk Assessment need not impair decision makers’ discretion, nor should it be used as an excuse for doing nothing in the face of evident harm. Good policy decisions require more than good intentions; they necessitate analysis of Risk-related information along with careful consideration of economic issues, ethical and moral principles, legal precedents, political realities, cultural beliefs, societal values, and bureaucratic impediments. Cumulative Risk Assessment can provide a systematic and impartial means for informing policy decisions about environmental justice.
