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America's Children and the Environment, Third Edition (ACE3)

Frequently Asked Questions

  1. What is America's Children and the Environment (ACE)?
  2. What are the purposes of ACE?
  3. What are children's environmental health indicators?
  4. Why did EPA focus on indicators for children?
  5. How were the topics and indicators in the third edition of America's Children and the Environment (ACE3) selected?
  6. What are the sources for the data in ACE3?
  7. What groups of children are included in ACE3?
  8. What years are included in ACE3?

What is America's Children and the Environment (ACE)?

America's Children and the Environment (ACE) is EPA's report presenting data on children's environmental health. ACE brings together information from a variety of sources to provide national indicators in the following areas:

  • Environments and Contaminants (conditions in the environment, such as levels of air pollution)
  • Biomonitoring (contaminants measured in the bodies of children and women of child-bearing age, such as children's blood lead levels)
  • Health (rates at which selected health outcomes occur among U.S. children, such as the annual percentage of children who currently have asthma)

Accompanying each indicator is text discussing the relevance of the issue to children's environmental health and describing the data used in preparing the indicator. Wherever possible, the indicators are based on data sources that are updated in a consistent manner, so that indicator values may be compared over time.

This report is the third edition of ACE (referred to as ACE3); previous editions of ACE were published in 2000 and 2003.

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What are the purposes of ACE?

ACE has three principal objectives:

  • First, it compiles data from a variety of sources to present concrete, quantifiable indicators for key factors relevant to the environment and children's health in the United States.
  • Second, it can inform discussions among policymakers and the public about how to improve data on children's health and the environment.
  • Third, it includes indicators that can be used by policymakers and the public to track trends in children's environmental health, and ultimately to help identify and evaluate ways to minimize environmental impacts on children.

EPA believes awareness of information on trends in children's environmental health is valuable and should be shared with the public. The purpose of ACE is to compile, and make available to a broad audience, information that can help identify areas that warrant additional attention, potential issues of concern, and persistent problems. Some of the indicators can also support efforts to evaluate whether past environmental policies and actions have been effective. EPA hopes that the development and presentation of these indicators will motivate continuing research, additional data collection, and, when appropriate, necessary interventions.

The information in ACE is not intended to serve as a definitive basis for planning specific policies or projects. EPA and other federal agencies rely on a wide range of technical information to inform their activities on children's environmental health. Emerging and ongoing research will help shape these efforts for years to come. The presentation of findings from the scientific literature in ACE is not intended to constitute an authoritative summary or conclusion on the weight of scientific evidence.

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What are children's environmental health indicators?

ACE defines an indicator as a quantitative depiction of an aspect of children’s environmental health that summarizes the underlying data in a relevant, understandable, and technically appropriate manner. The data may represent measurements of environmental conditions, of chemicals measured in the bodies of children and women of child-bearing age, or of the frequency of certain childhood diseases and health outcomes. Federal data on children’s environmental health issues come from a variety of agencies and are often very detailed and complex; ACE brings this information together into one report and summarizes the data in graphics that convey the key information. The ACE indicators generally focus on presenting data at the national scale in order to meet its three principal objectives, described above.

The World Health Organization defines environmental health as “all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviors. It encompasses the assessment and control of those environmental factors that can potentially affect health.” In concordance with this definition, ACE3 uses the terms “children’s environmental health” to refer to the external physical, chemical, and biological factors that are known to or may potentially affect children's health. Evidence of relationships between environmental exposures and children’s health continues to evolve for many of the indicators presented in this report. Inclusion of an indicator in ACE3 does not necessarily imply a known relationship between the environmental exposure and children’s health effect. EPA aims to develop increasingly informative indicators of children’s environmental health as more data become available to reduce these uncertainties.

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Why did EPA focus on indicators for children?

Environmental contaminants can affect children quite differently than adults, both because children may be more highly exposed to contaminants and because they are often more vulnerable to the toxic effects of contaminants.

Children generally eat more food, drink more water, and breathe more air relative to their size than adults do, and consequently may be exposed to relatively higher amounts of environmental contaminants. Children's normal activities, such as putting their hands in their mouths or playing on the ground, can result in exposures to chemicals that adults do not face. In addition, some environmental contaminants may affect children disproportionately because their bodies are not fully developed and their growing organs can be more easily harmed.

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In choosing indicators for ACE3, EPA considered a variety of factors, including public interest, magnitude of prevalence and/or trend in prevalence, extent of exposure, severity of health outcome, past EPA actions to address the issue, and research findings indicating or suggesting that an environmental exposure may contribute to children's health outcomes.

ACE3 includes updates and revisions to topics and indicators included in the 2003 ACE report, as well as new topics and indicators developed for this edition. The selection of topics involved generating a list of children's environmental health issues of potential interest, evaluating availability of suitable databases relevant to those topics, and considering indicators that might be derived from those databases. EPA obtained input from members of EPA's Children's Health Protection Advisory Committee (CHPAC) on each stage of this process, including input on the ultimate selection of topics and indicators presented in ACE3. EPA also obtained input from independent external peer reviewers regarding the suitability of the indicators and other information provided for each topic. EPA revised the report based on the peer review comments, and comments received from the public.

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What are the sources for the data in ACE3?

Federal agencies provided the data for most of the indicators. The data for the Environments and Contaminants indicators are generally from data systems maintained by EPA and by state environmental agencies. Data on indoor lead hazards are from surveys conducted by the U.S. Department of Housing and Urban Development. Pesticide residue data are from the Pesticide Data Program of the U.S. Department of Agriculture. Health and biomonitoring data are from the National Center for Health Statistics in the Centers for Disease Control and Prevention. Cancer data are from the National Cancer Institute. Child population data from the Census Bureau were used for calculations in several of the Environments and Contaminants indicators.

Data for the Supplementary Topics measures are from more targeted data collection efforts that illustrate some aspect of a children's environmental health issue of interest in the absence of a more comprehensive data source. Childcare facility measures are derived from a national study, and a study performed in North Carolina and Ohio. For schools, a measure on indoor pesticide application is derived from data reported by California schools and collected by the California Department of Pesticide Regulation. The data on birth defects are from the Texas birth defects monitoring program. Data from individual states are not intended to describe national conditions or conditions in other states.

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What groups of children are included in ACE3?

Census Bureau data indicate that there were 74.2 million children ages 17 years and younger in the United States in 2010. The age range used for each ACE3 indicator depends on data availability and the nature of the topic being addressed. Each indicator clearly identifies the age range in the title of the figure.

ACE3 presents (where possible) indicators for groups of children of different races and ethnicities and for children living in households with various levels of income. In some cases, these breakouts by race/ethnicity and family income are shown in the graphs, while in other cases they are included in the data tables. The specific race/ethnicity categories used for each indicator depend on the underlying data source, and are further discussed in the introduction to each section of the report.

Many of the indicators also provide separate indicator values for children living in homes with family income below poverty level and those in homes at or above poverty level. “Poverty level” is defined by the federal government and is based on income thresholds that vary by family size and composition. In 2010, for example, the poverty threshold was $22,113 for a household with two adults and two related children.

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What years are included in ACE3?

ACE3 aims to include indicators that present trends over at least 10 years; however, for some indicators, data are not available for this length of time. When sufficient data are not available to show changes over time, indicators present the most current data available, frequently focusing the presentation on demographic comparisons of race/ethnicity and income. Some topics include both a trend indicator and a separate indicator with demographic comparisons using current data. All ACE3 indicators incorporate the most current data that were available at the time of analysis.

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