Abstract  U.S. Department of Health and Human Services released the 14th Report on Carcinogens November 2016. The RoC is a congressionally mandated, science-based, public health document that NTP prepares for the HHS Secretary. This cumulative report currently includes 248 listings of agents, substances, mixtures, and exposure circumstances that are known or reasonably anticipated to cause cancer in humans.

Abstract  The mission of National Center for Environmental Assessment (NCEA) of EPA's Office of Research and Development is to provide guidance and risk assessments aimed at protecting human health and the environment. To accomplish this mission, NCEA works to develop and improve the models, databases, tools, assumptions, and extrapolations used in risk assessments. This handbook is a tool developed by NCEA aimed at refining the assumptions used in exposure assessments and reducing uncertainty. This handbook was first published in 1989 and later updated in 1997 to provide statistical data on the various human factors used in assessing exposure. This revised edition of the handbook provides the most up-to-date data on these exposure factors. The recommended values are based solely on our interpretations of the available data. In many situations different values may be appropriate to use in consideration of policy, precedent or other factors. The Exposure Factors Handbook provides a summary of the available statistical data on various factors used in assessing human exposure. This Handbook is addressed to exposure assessors inside the Agency as well as outside, who need to obtain data on standard factors to calculate human exposure to environmental agents. These factors include: drinking water consumption, soil ingestion, inhalation rates, dermal factors including skin area and soil adherence factors, consumption of fruits and vegetables, fish, meats, dairy products, homegrown foods, human milk intake, human activity factors, consumer product use, and building characteristics. Recommended values are for the general population and also for various segments of the population who may have characteristics different from the general population. NCEA has strived to include full discussions of the issues that assessors should consider in deciding how to use these data and recommendations.

Abstract  The ATSDR toxicological profile succinctly characterizes the toxicologic and adverse health effects information for the hazardous substance described here. Each peer-reviewed profile identifies and reviews the key literature that describes a hazardous substance's toxicologic properties. Other pertinent literature is also presented, but is described in less detail than the key studies. The complete list of topics covered (chapter titles) is shown at the left and in more detail further down this page. The focus of the profile is on health and toxicologic information. Therefore, each profile begins with a Public Health Statement that summarizes in nontechnical language, a substance's relevant properties. A useful two page information sheet, the ToxFAQs, is also available.

Abstract  In 1983, the National Academy of Sciences (NAS)/National Research Council (NRC) published its report entitled Risk Assessment in the Federal Government: Managing the Process. In that report, the NRC recommended that Federal regulatory agencies establish ""inference guidelines"" to promote consistency and technical quality in risk assessments and to ensure that the risk assessment process was maintained as a scientific effort separate from risk management. EPA responded to this recommendation by publishing a set of risk assessment guidelines in 1986, including the Guidelines for Carcinogen Risk Assessment (51 FR 33992, September 24, 1986). EPA began revising the 1986 cancer guidelines in light of significant advances in our understanding of the processes of carcinogenesis and the modes of actions of disease at the cellular level. Revising the cancer guidelines is in keeping with EPA's original intent when it issued the first set of final risk assessment guidelines in 1986. The risk assessment guidelines were meant to be dynamic, flexible documents that would evolve to reflect the current state of the science and risk assessment practices. In keeping with this, EPA undertook an effort to revise the cancer guidelines as described below in the History and Chronology section.

Abstract  Evaluation of environmental risks posed by potentially hazardous substances requires achieving a balance between over- and underprotection. i.e., between societal benefits posed by the use of particular substances and their potential risks. Uncertainty (e.g., only laboratory data may be available, field or epidemiological data may be limited and less than clear-cut, etc.) will always exist and is often conservatively dealt with by the use of so-called "safety" or "uncertainty" factors, some of which remain relatively little changed since their origin in 1945. Extrapolations involving safety factors for both aquatic and terrestrial environments include inter-and intraspecies, acute-to-chronic, lowest-to no-observed-effect concentration (NOEC), and laboratory-to-held extrapolation (e.g., extrapolation of laboratory results to the field). To be realistic, such extrapolations need to have a clear relationship with the field effect of concern and to be based on good science. The end result is, in any case, simply an estimate of a field NOEC, not an actual NOEC. Science-based versus policy-driven safety factors, including their uses and limitations, are critically examined in the context of national and international legislation on risk assessment. Key recommendations include providing safety factors as a potential threshold effects range instead of a discrete number and using experimental results rather than defaulting to safety factors to compensate for lack of information. This latter recommendation has the additional value of rendering safety factors predictive rather than simply protective. We also consider the so-called "Precautionary Principle," which originated in 1980 and effectively addresses risk by proposing that the safety factor should be infinitely large.

Abstract  EU chemicals legislation requires the use of all available information for hazard and risk assessment before new tests on vertebrates are proposed or conducted. In this context, extrapolation approaches for avoiding chronic fish testing on the basis of existing data have been explored. Simple linear relationships and interspecies sensitivity ratios between Daphnia and fish were calculated and acute-to-chronic relationships and ratios were calculated for fish, taking into consideration the mode of action. The best fitted relationships for the prediction of chronic fish toxicity are obtained based on acute fish and Daphnia data. Chemicals acting by unspecific reactivity and non-polar narcosis give the strongest acute and chronic Daphnia-to-chronic fish relationship. With acute fish data, strong relationships are obtained for all mode of action. Daphnia was found to be more sensitive than fish to several aniline derivatives and pesticides acting through cholinesterase inhibition, and less sensitive than fish to known endocrine disruptors. Extreme (i.e. <1 or >100) interspecies sensitivity ratios were mainly evident for chemicals acting by polar narcosis and specific reactivity. The safety factor of 100 commonly applied in environmental risk assessment does not seem to be equally protective for each mode of action.

Abstract  EPA’s Office of Pollution Prevention and Toxics (OPPT) Design for the Environment (DfE) project developed a wall paint exposure assessment model for interior latex and alkyd paints, in collaboration with the National Paints and Coatings Association (NPCA), paint manufacturers and chemical suppliers. The purpose of the model is to allow industry product developers and health and safety officials to more easily and accurately identify chemicals in paint formulations that may pose potential exposure problems. It is envisioned that identification and/or evaluation of potentially problematic chemicals will be done by individual paint manufacturers and chemical suppliers during the design stage of paint development and/or during a product-stewardship effort to fully assess a current line of products.