Expert Risk Assessment

Ruden C. (2004) Acrylamide and cancer risk - expert risk assessments and the public debate. Food and Chemical Toxicology 42 335-349. 

Ruden C. Acrylamide and cancer risk-expert risk assessments and the pubbc debate. Food Chem Toxicol 2004 42 335- 9. 

While public perception of risk is sometimes frustrating to expert risk assessors, it can serve a useful purpose by focusing attention on catastrophic risks that impact whole communities, not just individuals. The risk of a meltdown at a nuclear power plant is small, but the consequences are huge Witness Chernobyl and the continuing effects of radioactive contamination. In the difficult political business of managing risks, risk perception can complement expert risk assessment and help drive the regulatory process forward. 

The severe accident research program improved public risk assessment, reduced uncertainties, and the reliance on subjective expert opinion. To close two severe accident issues in NRC s Severe Accident Research Plan (NUREG-1365) Mark I Liner Attack and Direct Containment Heating (DCH) were addressed with a new approach using the Risk Oriented Accident Analysis Method (ROAAM) (Theofanous, 1994, 1989). The resolution of the Mark-I Liner Attack issue constitutes the first full demonstration of ROAAM. It emphasizes the determinism and provides a basis for synergistic collaboration among experts through a common communication frame. 

Lay people and experts disagree on risk estimates for many eiivironincntal problems. This creates a problem, since die public generally does not trust the experts. This chapter concentrates on how the public views risk and what the future of public risk perception will be. The reader should note that much of diis material, as with die previous Section, applies to liazard risk assessment- a topic that is treated in Chapter 19, Ptirt IV. 

Dr Georg Geisler is a product safety expert and modeller working with RCC Ltd, a Contract Research Organisation based in Basel, Switzerland. In this function, he conducts environmental risk assessments of pesticides, biocides and other chemicals, as well as safety assessments for pesticide residues in the food chain. In 2003, Georg Geisler earned his Ph.D. on environmental life-cycle assessment of pesticides at ETH Zurich. In 1999, he had received a Diploma in environmental chemistry at the Friedrich-Schiller University, Jena, Germany. 

In the authors opinion, even if imperfect, the CLL approach is preferable to apply for ecosystem risk assessment than a qualitative EcoRA based mainly on expert judgment. 

During the last two decades, a number of different risk assessments of dioxins and related compounds have been performed. Since the mid-1990s, coplanar PCBs have often been included in the assessments. In 1997, WHO established an expert group on dioxins and related compounds. 

Data on the safety studies were submitted to international agencies like the Joint Expert Committee for Food Additives of the WHO and FAO (JECFA), and the Scientific Committee on Food (SCF) of the EC. Both committees endorsed acesulfame K as a food additive. Initial acceptance was based on an NOEL of 900mg/kg in dogs which were considered to be the most sensitive species. Therefore Acceptable Daily Intake (ADI) values of 0-9 mg/kg of body weight were allocated.8 9 Evidence that rats would be an appropriate model for risk assessment was the reason for JECFA to change the ADI to 0-15 mg/kg of body weight on the basis of a no-effect level of 1500-3000 mg/kg in rats.10 Countries allocating their own ADI values like the USA and Canada have come to the same conclusion. The SCF still retains its 0-9 mg/kg ADI.11... 

The first edition1 of this book was published approximately 13 years ago. Its primary objective was to present an overview and a "roadmap" of the process of new drug discovery and development, particularly oriented to individuals or companies entering the pharmaceutical field. It was written by one of the authors (Smith), with no contributors, and drawn on Smith s experiences in the industry and field over the course of nearly 40 years. In the second edition, the scope of the first book has been expanded and technical details in the form of hard data have been included. In addition to the editors own commentary and contributions, the major part of the book is the result of contributions of experts in the industry. New chapters on risk assessment, international harmonization of drug development and regulation, dietary supplements, patent law, and entrepreneurial startup of a new pharmaceutical company have been added. Some of the important, basic operational aspects of drug discovery and development (e.g., organizational matters, staff requirements, pilot plant operations, etc.) are not repeated in this book but can be found in the first edition. 

If there are specific indications to suspect the presence of a harmful soil change or contaminated site, the proper authority may order the obliged persons to carry out necessary investigations and a risk assessment. The authority may require the carrying out of investigations and risk assessment by experts related to the requirements of Article 18 of the Act (Article 9 (2)). 

The magnitude of the dose is a function of the amount of chemical in the medium of contact, the rate of contact with the medium, the route of exposure, and other factors as well. Experts in exposure analysis use various means to estimate the dose incurred by individuals exposed to chemicals. Exposure analysis is one of the critical steps in toxicological risk assessment. 

Fortunately, well-developed methods exist for assessing the risks posed by chemicals to humans and the environment. The focus of this book is on the description of the existing risk assessment methodologies for human health. New developments in these methodologies will also be described. Throughout the book, the emphasis will be on international harmonization, and the application of test methods and guidance documents developed by international expert groups. The book only... 

Many other OECD activities on hazard/risk assessment are undertaken within programs such as Existing Chemicals, New Chemicals, and Pesticides and Biocides, which deal with specific types of chemicals. The work on exposure assessment methods is undertaken by the Task Force on Environmental Exposure Assessment, consisting of experts. Most of the outcome of this work is published in the Series on Testing and Assessment or in Emission Scenario Documents, which are available at the OECD Web site (OECD 2006a). 

US-EPA has formed the Risk Assessment Forum, a standing committee of senior US-EPA scientists, to promote US-EPA consensus on difficult and controversial risk assessment issues and to ensure that this consensus is incorporated into appropriate US-EPA risk assessment guidance. To fulhil this purpose, the Forum assembles US-EPA risk assessment experts in a formal process to study and report on issues from a US-EPA scientific perspective. Major Fomm guidance documents are developed in accordance with the US-EPA s regulatory and policy development process and become US-EPA pohcy upon approval by the Administrator or the Deputy Administrator. The Risk Assessment Forum products include risk assessment guidelines, technical panel reports on special risk assessment issues, and peer consultation and peer review workshops addressing controversial risk assessment topics. 

In the EU until 2003, the European Commission s Scientific Committee for Food (SCF) performed safety evaluations of food additives and contaminants. This task has now been taken over by the EFSA. EFSA s risk assessments and other scientific work are undertaken by its Scientific Committee and nine scientific Panels, each responsible for a different aspect of food and feed safety. The scientific work is also supported by external Scientific Expert Working Groups, each specializing in a specific subject (EFSA 2006). 

The WHO/IPCS international workshop on skin sensitization in chemical risk assessment (WHO/IPCS 2007) concluded (Q)SARs and expert systems for identification of sensitizing capacity have not been vahdated to date, but may be used as part of a weight of evidence approach for identifying the sensitizing capacity of chemicals. There are certain local (Q)SARs that can be used for a small range of chemicals. However, these are currently insufficient to cover the full range of chemicals. The Workshop recommended that QSAR models need to be further developed, and the apphcabihty domain of each model needs to be established. ... 

Probabilistic methods can be applied in dose-response assessment when there is an understanding of the important parameters and their relationships, such as identification of the key determinants of human variation (e.g., metabolic polymorphisms, hormone levels, and cell replication rates), observation of the distributions of these variables, and valid models for combining these variables. With appropriate data and expert judgment, formal approaches to probabilistic risk assessment can be applied to provide insight into the overall extent and dominant sources of human variation and uncertainty. 

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