Risk assessments evaluate potential adverse health effects posed by harmful chemicals found in the environment and inform a range of decisions from protecting air and water to ensuring food, drug, and consumer product safety. Unfortunately, the risk assessment process is bogged down by challenges to its timeliness and credibility, a lack of adequate resources, and disconnects between the available scientific data and the information needs of decision-makers. In light of these challenges, EPA asked the National Research Council to conduct an independent study on improvements that could be made to risk assessment. The report concludes that EPA’s overall concept of risk assessment, which is based on the National Research Council’s 1983 "Red Book," should be retained but that a number of significant improvements are needed to advance the use of risk assessment in decision making. Recommended changes include greater attention to planning and problem formulation, improved stakeholder involvement, and a better match of the level of detail needed in a risk assessment to the questions that should be addressed. The report also concludes that a unified approach to cancer and noncancer dose-response assessment is scientifically feasible and should be pursued.
The new field of toxicogenomics presents a potentially powerful set of tools to better understand the health effects of exposures to toxicants in the environment. At the request of the National Institute of Environmental Health Sciences, the National Research Council assembled a committee to identify the benefits of toxicogenomics, the challenges to achieving them, and potential approaches to overcoming such challenges. The report concludes that realizing the potential of toxicogenomics to improve public health decisions will require a concerted effort to generate data, make use of existing data, and study data in new ways—an effort requiring funding, interagency coordination, and data management strategies.
Toxicity Testing in the 21st Century: A Vision and a Strategy (2007)
Advances in molecular biology and toxicology are paving the way for major improvements in the evaluation of the hazards posed by the large number of chemicals found at low levels in the environment. The National Research Council was asked by the U.S. Environmental Protection Agency to review the state of the science and create a far-reaching vision for the future of toxicity testing. The report finds that developing, improving, and validating new laboratory tools based on recent scientific advances could significantly improve our ability to understand the hazards and risks posed by chemicals. This new knowledge would lead to much more informed environmental regulations and dramatically reduce the need for animal testing because the new tests would be based on human cells and cell components. Substantial scientific efforts and resources will be required to leverage these new technologies to realize the vision, but the result will be a more efficient, informative and less costly system for assessing the hazards posed by industrial chemicals and pesticides.
The emergence of toxicogenomics technologies hold much promise for helping scientists better understand the effects of exposures to chemicals in the environment. Toxicogenomic technologies enable researchers to study the genes expressed and the proteins and metabolites produced in response to a particular exposure. This report summarizes a National Research Council workshop on the validation of toxicogenomic technologies that focused on technical aspects of validation including experimental design, reproducibility, and the statistical and bioinformatics processing of toxicogenomic data. Workshop presentations and discussions among participants are summarized and address technical validation strategies and issues as well as challenges associated with the biological validation of these technologies.
Effectively communicating the promise of new technologies can be challenging, particularly when the science is not yet fully developed and its application is not well defined and understood. Toxicogenomics meshes toxicology with genomic technology (study of the entire expanse of genetic information in an organism) and may hold the promise of detecting changes in the expression of a person’s genes if he or she is exposed to toxicants. As the technology develops and more data become available, it is important that scientists and the public discuss the promises and limitations of this new field. The Committee on Communicating Toxicogenomics Information to Nonexperts designed a workshop to consider strategies for communicating toxicogenomics information to the public and other nonexpert audiences, specifically addressing communication issues surrounding some key social, ethical, and legal issues related to toxicogenomics and how information related to the social implications of toxicogenomics may be perceived by nonexperts.
Toxicogenomic Technologies and Risk Assessment of Environmental Carcinogens: A Workshop Summary (2005)
Toxicogenomics is a discipline that combines expertise in toxicology, genetics, molecular biology, and environmental health to help understand the response of living organisms to stressful environments. The National Research Council convened a workshop to discuss how toxicogenomic data could be applied to improve risk assessments, particularly cancer risk from environmental exposure to chemicals. Risk assessments serve as the basis of many public-health decisions in environmental, occupational, and consumer protection from chemicals. The workshop provided a forum for communities of experts, including those working in “-omics” and those in the policy arena, to discuss where their fields intersect, and how toxicogenomics could address critical knowledge gaps in risk assessments.
Some of what we know about the health effects of exposure to chemicals from food, drugs, and the environment come from studies of occupational, inadvertent, or accident-related exposures. When there is not enough human data, scientists rely on animal data to assess risk from chemical exposure and make health and safety decisions. However, humans and animals can respond differently to chemicals, including the types of adverse effects experienced and the dosages at which they occur. Scientists in the field of toxicogenomics are using new technologies to study the effects of chemicals. For example, in response to a particular chemical exposure, they can study gene expression (“transcriptomics”), proteins (“proteomics”) and metabolites (“metabolomics”), and they can also look at how individual and species differences in the underlying DNA sequence itself can result in different responses to the environment. Based on a workshop held in August 2004, this report explores how toxicogenomics could enhance scientists’ ability to make connections between data from experimental animal studies and human health.