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IRAC Work Group Descriptions

Nanotechnology and Risk Assessment Work Group Description

Background: So far there is no record, world wide, of a Risk Assessment for any engineered nanomaterial or any product that claims to include nanotechnology manufactured materials. Nevertheless, an important number of opinions and reports have been published on the feasibility of current Risk Assessment frameworks for engineered nanomaterials. Most of the published reports and opinions on nanotechnology, if not all, highlight a number of issues that need to be addressed for the development of a Risk Assessment; in summary these issues concern:

The above issues carry, inherently, high levels of uncertainty, and, consequently they may have effects on relevant regulatory procedures.

Goal: “Apply a “straw man” approach with the view to identifying the scientific challenges that need to be met in order to perform a Risk Assessment for engineered nanomaterials”. It was decided that such an objective could be met by following a series of steps:

In order to encompass as many as possible of the unknown factors and uncertainties relevant to risks and benefits of engineered nanomaterials to public health the group will be working with a number of hypothetical products that might reflect real scenarios and applications for all three exposure routes: dermal, oral, and inhalation that would relate to the objectives of many federal agencies.

Susceptible Populations Workgroup

Members of the Susceptible Populations workgroup (as representatives of IRAC) are working with the IOM Food Forum to organize a two day workshop on susceptibility in the aging population which will be held October 29-30 at the National Academy.  The IRAC workgroup is now in the process of identify the best dates to hold the supplementary 1.5 day workshop focusing on other susceptible populations (such as the very young, pregnant woman, and the immune compromised).  The workgroup has developed a structure for the workshop in which all the participants will start by looking at cross-cutting issues and data resources,  followed by breakout sessions focusing on issues specific to either chemical or biological hazards.  At the end of the workshop, the entire group will reconvene to integrate the results from the breakout groups.  The overall goal of the workshop will be to review what is known about the make up of the susceptible populations for the different types of hazards, the level of susceptibility in these populations, and the data available to quantify the size of each population.  The workshop participants will be asked to identify and prioritize critical data gaps identified during these reviews.  The workgroup is in the process of filling in the details of the agenda and indentifying specific speakers and participants.

Nutritional Risk Assessment

Lead: Michael McElvaine

Members:  Mary Brandt, Clark Carrington, Nancy Crane, Rita Deng, Sherri Dennis, Alison Edwards, Vasilios Frankos, Kathleen Koehler, Wesley Long, Michael McElvaine, Marianne Miliotis Donna Robie, Etta Saltos, Jan Stanton, Christine Taylor

Description: Over the past 20+ years the tools of risk analysis, Originally developed from systems engineering and later toxicology issues have been applied to health effects of biological stressors such as bacteria, viruses, chemical and drug contaminants, ecological systems, and more. There has been much recent discussion among scientists in the human health fields to look at the application of the risk analysis paradigm on issues of nutrition in humans and health endpoints caused by either excesses or deficiencies of certain nutrients.

Nutritional risk assessment may provide several unique issues:

  1. Nutrition provides a novel area of analysis because health effects can be either positive or negative and indeed can run the gamut from negative to positive to negative depending on the total exposure (dose). The concept of hormesis may be pertinent to nutritional examples. For example, "Selenium is a trace mineral needed in small amounts for good health, but exposure to much higher levels can result in neurological effects and brittle hair and deformed nails." (ToxFAQs* for Selenium, http://www.atsdr.cdc.gov/tfacts92.html.

  2. Nutritional issues may also result in risk-risk trade off such as fish consumption for intake of healthy fatty acids for nerve development when these fish may have concentrated contaminants such as dioxin and methylmercury which could have detrimental effects if exposure is high.

    Another issue might be pesticides on fresh fruit and vegetables. There may be a possibility of pesticides harming a developing child by blocking the absorption of food nutrients necessary for normal growth.

  3. A third novel area may be the interaction of nutrients with potential toxins. An example would be the increased absorption of lead from the intestines of children who are on a calcium deficient diet. This interaction between lead and calcium may also come into play when a new mother begins lactating. If there is lead in her bones, it may be mobilized along with the calcium necessary for milk production and lead to higher than expected levels of lead exposure to the nursing infant.

    Other aspects of nutritional risk that can also be considered include:
    Malnutrition; Overnutrition; Nutrition imbalance; Effect of low Carbohydrate diet; Effect of decreasing folates in the diet.

    4. Potential activities of this work group would be a review of current literature on the different types/aspects/issues of nutrition and risk assessment, identify and contact researchers who have been working in the area to invite their input, develop a white paper on the state of the art at the present, bring in speakers to quarterly IRAC meetings, or plan a symposium with a goal of producing a substantial document or proceedings.

Data Gaps Analysis

Lead: Andy Hwang

Members: Sherri Dennis, John Hicks, Janell Kause, Lynda Kelley, Mark Tamplin

Description: The primary objectives of this work group were to identify data gaps in current (and potentially in-progress) microbial risk assessments, to consolidate data gaps into one document, and to communicate the data gaps via the Clearinghouse website.

Data Utility

Lead: Brandolyn Thran

Members:  Sharon Edelson Mammel, Heather Hicks Quesenberry, Andy Hwang, Wes Long, Michael McElvaine, Marianne Miliotis, Margaret Venuto

Description: There is much interest and support for the topic of adequately designing future sampling plans and the appropriateness and applicability of data that has been collected by other researchers.   These topics are of interest because    sampling plan design impacts the utility of data for risk assessments.

To ensure sampling programs have a sound scientific foundation two essential things must be present, appropriate analytical methods that have been validated for their intended use, and a statistically valid sample size.  In the absence of these two components, the degree of confidence regarding the data generated by the sampling program may be in jeopardy.  The limitation of resources (time, money and people) impact and influence the development of any sampling program. 

The Data Utility work group has organized a symposium that acted as a retrospective analysis of data collection strategies from a “lessons learned” perspective.  The lessons highlighted from the initial symposium are shaping the future efforts of the workgroup as it focuses on the data utility characteristics of representativeness, relevancy, robustness, validity and defensibility. 

Data and Information Quality Guidelines

Lead: Carl Schroeder

Members: Mary Bartholomew, Sherri Dennis, Kara Morgan, Brandolyn Thran

Description:
Data quality is essential to risk assessment. Guidelines for determining which data to include in risk assessments are needed to improve risk assessment methodology. Furthermore, development of a uniform system of weight of evidence included in risk assessments would likely help in developing predictions that more accurately reflect the real world. The workgroup is in the process of summarizing feedback from a “Best Practices” survey circulated among RAC members in 2004. The results of the survey will be presented in a briefing paper in 2005.

Dose-Response Work Group on mechanistic dose–response data

Lead: Neal Golden

Members: Steve Anderson, Dennis Kopecko, Robert Hall, Lynda Kelley, Marianne Miliotis, Richard Raybourne, Steve Schaub, Angelo Turturro

Description: Continue compilation of data on variability among the three elements of the disease triangle (host, pathogen, and environment, with interactions) to extend current dose-response models in a more mechanistic rather than empirical perspective.  Scope of the work group in FY 2005 will emphasize mechanistic data: relative measures of host susceptibility; pathogen variability measured from in vitro and animal and human clinical studies; rates of pathogen excretion and attachment; rates of host cell sloughing, repair, and lesion formation; efficacy of host physiological and immune defenses; and biomarkers for activation of immune defenses.  The work group may engage researchers through NIH, CSREES, and other means to examine a broad range of food and water-borne pathogens, potentially including Listeria monocytogenes, Campylobacter jejuni/coli, EHECs, Salmonella spp., and Cryptosporidium.  In addition to a focus on data and models, the expansion in membership and frequency of work group meetings will provide more opportunities to address more specifically the data gaps for dose-response modeling that offer potential clarification using mechanistic approaches.

Peer Review

Co-Leads: Janell Kause, Mary Bartholomew

Members: David Goldblatt, Barry Hooberman, Jacqueline McQueen, Marianne Miliotis, Stephen Schaub

Description:

Over the past twenty years, there has been a growing interest in the use of analytic tools such as risk assessment and cost-benefit analysis to improve the scientific basis and transparency for decision-making within the regulatory process. These tools, required under various executive orders since the 1980s (Executive Order 12291 and Executive Order 12866) have been put forth by the Executive branch to ensure regulatory agencies develop reasonable regulations that improve public health and weigh the costs to the industry.  In part, the reasonableness of public health regulations is influenced by the quality of the science used to inform risk management decisions.  The Information Quality Act (IQA), sometimes referred to as the Data Quality Act, was enacted in December 2000 as Section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (P.L. 106-554). The act required the Office of Management and Budget (OMB) to issue guidance to federal agencies designed to ensure the "quality, objectivity, utility, and integrity" of information disseminated to the public.  To assure scientific information released to the public meets these criteria, OMB released a final bulletin to federal agencies on the conducting peer reviews of these types of information.  This Bulletin establishes minimum standards for when peer review is required for scientific information and the types of peer review that should be considered by agencies in different circumstances. The conduct of peer review of risk assessments varies among food safety regulatory agencies as evidenced by presentations provided as the RAC peer review workgroup co-hosted symposium on peer review in September 2003.  This workgroup is evaluating the various approaches federal agencies have taken to conduct a peer review of food safety risk assessment based on the criteria provided in the Information Quality Act.  From this evaluation, a concept paper is being developed.

Risk-Risk

Lead:  David Carlson

Members:  Abdel Kadry, Stephen Schaub, Angelo Turturro, Mark Walderhaug

Description:  The project will address cross-Agency issues relevant to risk-risk comparisons and tradeoffs, especially the balancing of chemical and microbial risk.  Currently, the workgroup is identifying and supporting presentations at RAC meetings on the topic of risk-risk assessments to:  (1) learn about important risk-risk issues that member agencies have previously dealt with, and, (2) determine how the risk-risk workgroup can help their agencies and whether there are specific needs or questions the agencies have regarding risk-risk issues.

The goal of the workgroup is to create a white paper to help guide IRAC member agencies faced with risk management decisions that include risk tradeoffs and 'risk-risk' scenarios.  Possible factors to consider include: