Society For Risk Analysis Annual Meeting 2017

Session Schedule & Abstracts

* Disclaimer: All presentations represent the views of the authors, and not the organizations that support their research. Please apply the standard disclaimer that any opinions, findings, and conclusions or recommendations in abstracts, posters, and presentations at the meeting are those of the authors and do not necessarily reflect the views of any other organization or agency. Meeting attendees and authors should be aware that this disclaimer is intended to apply to all abstracts contained in this document. Authors who wish to emphasize this disclaimer should do so in their presentation or poster. In an effort to make the abstracts as concise as possible and easy for meeting participants to read, the abstracts have been formatted such that they exclude references to papers, affiliations, and/or funding sources. Authors who wish to provide attendees with this information should do so in their presentation or poster.

Common abbreviations

Risk-Informed Priority Setting: Methods and Challenges

Room: Salon J   10:30 am–12:00 pm

Chair(s): Amir Mokhtari, David Oryang

Sponsored by Microbial Risk Analysis Specialty Group

T2-H.1  10:30 am  Developing and Using Decision Analysis Tools for the FDA Foods Program – A Decade of Continual Improvement. Oryang DO*, Fanaselle W, Van Doren J, Dennis S; CFSAN, FDA

Abstract: Decision analysis evaluates the complex alternatives surrounding a decision, in terms of values and uncertainty, and is the systematic process of unraveling, explaining, and documenting the key components and implications of a decision. It is among the evidence-driven, risk-based approaches FDA uses to target, evaluate, and prioritize a multitude of food-safety issues. Using a case-study approach, this presentation will review the general process we use to develop evidence-driven, risk-based decision-analysis tools, with a focus on multi-criteria decision analysis methodology that utilizes risk-modeler and decision-maker (risk-manager) teams; i.e., the two primary teams involved in the decision-making process. We will discuss several key lessons learned from our experience, including the need for the modeling team to engage decision-makers early in the process, to ensure a good understanding of the decision to be made, the alternatives to be considered, and any constraints that may impact the modeling. Discussion of the need for the modeling team to undertake some data collection and exploration of the issues in this often-iterative process will be included. We will also discuss the importance of identifying the appropriate public-health criteria and collecting data that inform the tool as to the criteria to be established, to ensure that the decision model is appropriately risk-based. Other decision criteria, such as feasibility or socio-economic factors, also may be considerations in a given decision, and we will discuss how these are included. The case studies we present will include tools designed to prioritize animal-drug residues, for milk-testing programs; firms, for inspection planning; and research projects, for resource allocation.

T2-H.2  10:50 am  A Performance-Based Method for Microbial Risk Assessment for Organizations. McClellan GE*, Coleman ME; Applied Research Associates, Inc.

Abstract: Health risk assessment for biological pathogens differs substantially from health risk assessment for chemical agents (and biological toxins). For chemical agents, the health effects of exposure progress from mild to moderate to severe as the dose increases. Mortality rates are usually low for doses causing mild or moderate effects but can increase rapidly for doses causing severe effects. Thus, exposure guidelines can be determined for mild (or threshold) effects to individuals with minimal consequences for the functioning of an organization. On the other hand, for biological pathogens, infection can progress through mild, moderate, and severe stages, sometimes leading to death with only weak dependence on the initiating dose. Due to potential for exponential growth of pathogens, outcomes of illness may be less tied to the initial pathogen dose than is the outcome of injury due to a chemical agent. Consequently, setting exposure guidelines for pathogens requires different considerations than for chemicals. A framework for assessing organizational risk was built based on a legacy model for the time-phased health effects of pneumonic tularemia in 112 human volunteers administered known doses of the bacterial pathogen Francisella tularensis. This legacy model provides well-founded statistical distributions of individual fever profiles as a function of inhaled pathogen dose. Parameterizations are available for length of incubation period, the rise-time of fever, and the peak fever for early-phase illness. The resulting fever profile of each individual then determines the performance capability of each individual as a function of time-after-exposure. The distribution of personnel performance capabilities within an organization (the personnel status) is then connected to a hazard severity measure according to the functional needs of the organization. Thus, extension of the legacy model permits generation of time-and dose-dependent exposure guidelines and characterization of organizational risk for biological pathogens.

T2-H.3  11:10 am  Source attribution at the sub-product level for 32 pathogen-commodity combinations for the development of the Canadian Food Inspection Agency Establishment-based Risk Assessment model. Zanabria R*, Racicot M, Leroux A, Arsenault J, Ferrouillet C, Griffiths M, Holley R, Gill T, Charlebois S, Quessy S; Canadian Food Inspection Agency

Abstract: The Canadian Food Inspection Agency is modernizing its risk-based approach to oversight by developing the Establishment-based Risk Assessment (ERA) model to enhance a more effective allocation of resources to highest-risk areas. In 2013/14, two expert elicitations selected the most important risk factors for the model, and assigned weights to the assessment criteria based on human health’s relative risk. As the model assesses establishments’ food safety risks at the sub-product level, a third expert elicitation was needed considering no studies were available on this area. The process was conducted in 2016 (January to August 2016), and the foodborne illness burden at the sub-product level for 32 pathogen-commodity combinations was estimated. Targeted pathogens and commodities included Campylobacter, Salmonella non thyphoidal, Norovirus, Shiga toxin producing E. coli, Toxoplasma gondii, Clostridium perfringens, Listeria monocytogenes and Yersinia enterocolitica in beef, pork, poultry, game, dairy, fish/seafood, produce and eggs/egg products. The number of sub-products within each commodity varied from 4 (eggs) to 13 (dairy). A snow-ball approach resulted in 119 Canadian experts being invited to participate on a web-based survey (available in English/French). Experts provided estimates for each pathogen-commodity combination and evaluated their level of certainty using a scale from 1 (low certainty) to 10 (high certainty). Forty-nine experts from industry, government and academia with over 18 years’ experience (average) participated in the study. Data analysis compared 3 different approaches: (1) weight experts’ estimates according to their certainty level, (2) remove estimates with a certainty level ≤2, and a combination of (1) and (2). No significant differences were found among the results obtained with the 3 methods. Thus, the first approach was chosen and the estimates for the attribution of risks at the sub-product level were included in the ERA model.

T2-H.4  11:30 am  Methodological lessons learnt from developing a risk-benefit assessment applied to infant milk-based diet. Boué G*, Cummins E, Guillou S, Antignac JP, Le Bizec B, Membré JM; Oniris / INRA

Abstract: The objective of this study was to develop a conceptual and methodological framework to assess quantitatively the overall impact of food on human health, including microbiological, chemical and nutritional dimensions. This methodology was developed using a case study related to infant milk-based diet (breast milk and infant formulas) taking into account the following selected factors: Cronobacter sakazakii, Cryptosporidium, arsenic, dioxin-like polychlorinated biphenyls and docosahexaenoic acid. Five probabilistic mathematical models were developed to quantify risks / benefits associated with these factors. In this communication main outputs obtained on the case-study will be presented as well as lessons learnt in terms of “Risk-Benefit Assessment” methodology. Probabilistic techniques enabled the consideration of the variability (heterogeneity between individuals of the same population) and the uncertainty linked to the lack of knowledge and data. Separation of variability and uncertainty, using second-order Monte Carlo simulation, strengthened the evaluation by enabling a more accurate interpretation of results and by providing more comprehensive information to policy makers. The DALY metric was used in this study to compare the health effects originated from different factors. Although very attractive in integrating the whole complex RBA issue within a simple figure, this metric might not be an intuitive metric to communicate results to stakeholders (too integrative to be understood). Finally, a multi-criteria table was built to incorporate in a transparent and comprehensive manner the various outputs of the risk-benefit assessment (e.g. DALY, number of case, individual probability of illness, etc.), a promising technique to facilitate decision-making. The methodological framework developed in the present study can be considered as a robust basis for risk-benefit assessment in foods and results obtained will enable to progress on the evaluation of infant milk-based diet.

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