The U.S. Environmental Protection Agency (EPA) has a mission and regulatory responsibility to protect human health and the environment. EPA's pursuit of that goal includes a variety of research activities involving human subjects, such as epidemiologic studies and surveys. Those research activities also involve studies of individuals who volunteer to be exposed to air pollutants intentionally in controlled laboratory settings so that measurements can be made of transient and reversible biomarker or physiologic responses to those exposures that can indicate pathways of toxicity and mechanisms of air-pollution responses. The results of those controlled human inhalation exposure (CHIE) studies, also referred to as human clinical studies or human challenge studies, are used to inform policy decisions and help establish or revise standards to protect public health and improve air quality. Controlled Human Inhalation-Exposure Studies at EPA addresses scientific issues and provides guidance on the conduct of CHIE studies. This report assesses the utility of CHIE studies to inform and reduce uncertainties in setting air-pollution standards to protect public health and assess whether continuation of such studies is warranted. It also evaluates the potential health risks to test subjects who participated in recent studies of air pollutants at EPA's clinical research facility.

The U.S. Environmental Protection Agency (EPA) has a mission and regulatory responsibility to protect human health and the environment. EPA's pursuit of that goal includes a variety of research activities involving human subjects, such as epidemiologic studies and surveys. Those research activities also involve studies of individuals who volunteer to be exposed to air pollutants intentionally in controlled laboratory settings so that measurements can be made of transient and reversible biomarker or physiologic responses to those exposures that can indicate pathways of toxicity and mechanisms of air-pollution responses. The results of those controlled human inhalation exposure (CHIE) studies, also referred to as human clinical studies or human challenge studies, are used to inform policy decisions and help establish or revise standards to protect public health and improve air quality. Controlled Human Inhalation-Exposure Studies at EPA addresses scientific issues and provides guidance on the conduct of CHIE studies. This report assesses the utility of CHIE studies to inform and reduce uncertainties in setting air-pollution standards to protect public health and assess whether continuation of such studies is warranted. It also evaluates the potential health risks to test subjects who participated in recent studies of air pollutants at EPA's clinical research facility.

The EPA commissioned The National Academies to provide advice on the vexing question of whether and, if so, under what circumstances EPA should accept and consider intentional human dosing studies conducted by companies or other sources outside the agency (so-called third parties) to gather evidence relating to the risks of a chemical or the conditions under which exposure to it could be judged safe. This report recommends that such studies be conducted and used for regulatory purposes only if all of several strict conditions are met, including the following: The study is necessary and scientifically valid, meaning that it addresses an important regulatory question that can't be answered with animal studies or nondosing human studies; The societal benefits of the study outweigh any anticipated risks to participants. At no time, even when benefits beyond improved regulation exist, can a human dosing study be justified that is anticipated to cause lasting harm to study participants; and All recognized ethical standards and procedures for protecting the interests of study participants are observed. In addition, EPA should establish a Human Studies Review Board (HSRB) to evaluate all human dosing studiesâ€"both at the beginning and upon completion of the experimentsâ€"if they are carried out with the intent of affecting the agency's policy-making.

Most people in the United States spend far more time indoors than outdoors. Yet, many air pollution regulations and risk assessments focus on outdoor air. These often overlook contact with harmful contaminants that may be at their most dangerous concentrations indoors. A new book from the National Research Council explores the need for strategies to address indoor and outdoor exposures and examines the methods and tools available for finding out where and when significant exposures occur. The volume includes: A conceptual framework and common terminology that investigators from different disciplines can use to make more accurate assessments of human exposure to airborne contaminants. An update of important developments in assessing exposure to airborne contaminants: ambient air sampling and physical chemical measurements, biological markers, questionnaires, time-activity diaries, and modeling. A series of examples of how exposure assessments have been applied-properly and improperly-to public health issues and how the committee's suggested framework can be brought into practice. This volume will provide important insights to improve risk assessment, risk management, pollution control, and regulatory programs.

Incineration has been used widely for waste disposal, including household, hazardous, and medical wasteâ€"but there is increasing public concern over the benefits of combusting the waste versus the health risk from pollutants emitted during combustion. Waste Incineration and Public Health informs the emerging debate with the most up-to-date information available on incineration, pollution, and human healthâ€"along with expert conclusions and recommendations for further research and improvement of such areas as risk communication. The committee provides details on: Processes involved in incineration and how contaminants are released. Environmental dynamics of contaminants and routes of human exposure. Tools and approaches for assessing possible human health effects. Scientific concerns pertinent to future regulatory actions. The book also examines some of the social, psychological, and economic factors that affect the communities where incineration takes place and addresses the problem of uncertainty and variation in predicting the health effects of incineration processes.

This book presents WHO guidelines for the protection of public health from risks due to a number of chemicals commonly present in indoor air. The substances considered in this review, i.e. benzene, carbon monoxide, formaldehyde, naphthalene, nitrogen dioxide, polycyclic aromatic hydrocarbons (especially benzo[a]pyrene), radon, trichloroethylene and tetrachloroethylene, have indoor sources, are known in respect of their hazardousness to health and are often found indoors in concentrations of health concern. The guidelines are targeted at public health professionals involved in preventing health risks of environmental exposures, as well as specialists and authorities involved in the design and use of buildings, indoor materials and products. They provide a scientific basis for legally enforceable standards.

This book is the eighth volume in the series Acute Exposure Guideline Levels for Selected Airborne Chemicals, and reviews AEGLs for acrolein, carbon monoxide, 1,2-dichloroethene, ethylenimine, fluorine, hydrazine, peracetic acid, propylenimine, and sulfur dioxide for scientific accuracy, completeness, and consistency with the NRC guideline reports.

Air Emissions from Animal Feeding Operations: Current Knowledge, Future Needs discusses the need for the U.S. Environmental Protection Agency to implement a new method for estimating the amount of ammonia, nitrous oxide, methane, and other pollutants emitted from livestock and poultry farms, and for determining how these emissions are dispersed in the atmosphere. The committee calls for the EPA and the U.S. Department of Agriculture to establish a joint council to coordinate and oversee short - and long-term research to estimate emissions from animal feeding operations accurately and to develop mitigation strategies. Their recommendation was for the joint council to focus its efforts first on those pollutants that pose the greatest risk to the environment and public health.