At the request of the Environmental Protection Agency, the National Research Council (NRC) recently completed a major report entitled Toxicity Testing in the 21st Century: A Vision and a Strategy. The terms of reference for this report were to develop a long‐range vision and strategic plan to advance the practices of toxicity testing and human health assessment of environmental agents. The report describes how current and anticipated scientific advances can be expected to transform toxicity testing to permit broader coverage of the universe of potentially toxic chemicals to which humans may be exposed, using more timely and more cost‐effective methods for toxicity testing. The report envisages greatly expanded use of high‐ and medium‐throughput in vitro screening assays, computational toxicology, and systems biology, along with other emerging high‐content testing methodologies, such as functional genomics and transcriptomics. When fully implemented, the vision will transform the ways toxicity testing and chemical risk assessment are conducted, moving away from measuring apical health endpoints in experimental animals toward identification of significant perturbations of toxicity pathways using in vitro tests in human cells and cell lines. Population‐based studies incorporating relevant biomarkers will also be useful in identifying pathway perturbations directly in humans and in interpreting the results of in vitro tests in the context of human health risk assessment. The present article summarizes and extends the NRC report and examines its implications for risk assessment practice.

In the field of risk analysis, there is ongoing tension between expert risk assessment and public risk perception. This paper presents the results of a health risk perception survey administered to Canadian health experts as a follow-up to a previous survey. A total of 125 experts (75 physicians and 50 toxicologists) recruited through professional organizations completed a self-administered questionnaire in 2004. Experts were asked to provide ratings of perceived risk of 30 health hazards as well as detailed ratings of five health hazards (motor vehicles, climate change, recreational physical activity, cellular phones, and terrorism) and five health outcomes (cancer, long-term disabilities, asthma, heart disease, and depression) in terms of perceived health risk, personal control, knowledge, uncertainty, worry, and acceptability. Sources of information on health risks, confidence in those information sources, as well as health risk beliefs were also examined. Experts perceived behavioral health hazards, such as cigarette smoking, obesity, and physical inactivity, posed the greatest health risk, and medical technologies, including vaccines, medical X-rays, and laser eye surgery, posed the least risk. Experts reported receiving ‘a lot’ of information from university scientists/scientific journals and medical doctors and reported having ‘a lot’ of confidence in those sources. High levels of environmental and social concern were observed, as well as a high degree of personal agency over health risks. Health risk perceptions varied by professional affiliation but not gender. Results are compared to a recent public risk perception survey in Canada. Differences between public and expert risk perceptions may hold instructive pointers for risk management and risk communication strategies designed to improve population health.

While its precise form has not yet been defined, it is assumed that the exposure-response curve for copper (Cu) is U-shaped, as both Cu deficiency and excess can produce adverse health effects. Exposure-response relationships provide the foundation for setting recommended levels of exposure to essential and nonessential substances. A group of toxicologists, biologists, and epidemiologists formed a working group in 2002 to review the literature on Cu excess and deficiency as well as possible exposure-response modeling strategies. It was decided that in order to conduct more complex modeling exercises with studies on Cu, the information had to be organized into a database for application of emerging analytical approaches in exposure-response assessment. The database would support both current as well as proposed methods for exposure-response assessment and accommodate a variety of reporting methods found in the literature. As there are multiple studies looking at a wide range of adverse health effects attributed to excess and deficiency, data were organized into ordered categories of severity to create a common measure of response. The present study (1) outlines the approach used to identify studies for the Cu database based on their quality and usefulness for exposure-response analyses; (2) provides an overview of the process used to define a common dose metric; and (3) describes the process used to categorize a diverse number of responses from Cu excess and deficiency to an ordinal severity score. Efforts are underway to use this database to define the exposure-response curve for Cu excess and deficiency; however, the comprehensive database can be used to carry out other in-depth analyses on Cu toxicity.

A national survey of health risk perception among 1,503 adult Canadians was conducted in 2004 as a follow-up to a previous survey in 1992. Respondents were asked to indicate their personal opinion regarding a range of risk perception belief statements reflecting environmental concern, social concern, genetic concern, dependence on regulators, locus of health risk control (internal, powerful others, chance), risk acceptability and technological enthusiasm. The results indicated considerable concern over the state of the environment in general, however, less concern existed for the environment nearest to the individual. A high degree of concern was expressed over stress in the workplace, and poverty was perceived to represent an important health risk for Canadians. A strong sense of the importance of personal lifestyle factors and personal control over one's health was also observed as were notable increases in trust and dependence on the ability of government and experts to make decisions and regulate health risks in Canada as compared to the previous survey. Belief statements reflecting environmental and social concern correlated with the level of risk perceived for a variety of health hazards and outcomes.