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Appendix B - America's Children and the Environment: A First View of Available Measures


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Data Source Descriptions

Common Air Pollutants

Air Quality Exceedances

EPA's Office of Air Quality Planning and Standards has set health-based National Ambient Air Quality Standards (NAAQS) for six common pollutants, often referred to as criteria pollutants. These standards are shown in Table 1 below.

State and local environmental agencies conduct air monitoring programs to measure concentrations of these pollutants. The individual measurements are submitted to EPA for inclusion in a national database called the Aerometric Information Retrieval System.

EPA, as part of its data management system, identifies instances in which levels of air pollutants measured in the air are greater than the air quality standards. Each of these events is called an "exceedance." An exceedance occurs when a measured concentration exceeds a target value that is actually higher than the air quality standard. Concentrations measured in the air must be averaged over a time period set in accordance with the standard for that pollutant. The target values used to identify exceedances are shown in Table 1 below.



Table 1: National Ambient Air Quality Standards (NAAQS) and the Values Used to Define Exceedances by EPA
Pollutant Duration of Standard Standard Target value to define exceedance
Carbon monoxide Eight-hour average
One-hour average		 9 ppm
35 ppm		 9.5 ppm
Not applicable
Nitrogen oxide One-year average 0.053 ppm
0.0535 ppm
Ozone One-hour average a
Eight-hour average		 0.12 ppm
0.08		 0.125 ppm
Not applicable
Lead Three-month average 1.5 µg/m3 1.55 µg/m3
Particulate matter under 10 microns One-day (24 hour average
One year average		 150 µg/m3
50 µg/m3		 155
Not applicable
Sulfur dioxide One-day (24 hour) average
One year average		 0.14 ppm
0.03 ppm		 0.145 ppm
Not applicable
a The ozone 1-hour standard applies only to areas that were designated non-attaintment when the ozone 8-hour standard was adopted in July 1997.

To use these data in measure E1, for carbon monoxide and ozone, we identified counties in which air quality exceeded the one-hour standards at any time during the year. For particulate matter and sulfur dioxide we identified counties in which the one-day standards were exceeded at any time during the year. For nitrogen dioxide, we identified counties in which air quality exceeded the standard for the year, and for lead we identified counties in which air quality exceeded the lead standard for a three-month period.

Agency Contact:
David Mintz (mintz.david@epa.gov)
U.S. EPA, Office of Air Quality
Planning and Standards (OAQPS)
Tel: (919) 541-5224

Air Quality Index

EPA uses the Air Quality Index (AQI) to evaluate daily air quality for five major pollutants for which it has established NAAQS under the Clean Air Act. The AQI is an update of the Pollutant Standards Index (PSI). Both indices convert the measured pollutant concentration in a community's air to a number on a scale of 0 to 500. The most important number on this scale is 100, which corresponds to the NAAQS for each pollutant established under the Clean Air Act. A PSI or AQI level in excess of 100 means that a pollutant is in the unhealthy range on a given day; a PSI or AQI level at or below 100 means that a pollutant reading is in the satisfactory range. Once these levels are measured, the PSI or AQI figures are reported in all metropolitan areas of the United States with populations exceeding 200,000. Data on the PSI are used in this report, since we have historical data for the PSI. New data for the AQI will be incorporated as the data become available. Information on the AQI can be found at http://www.epa.gov/airnow/aqibroch/.

Detailed information on the PSI data is presented in the following:

Agency Contact:
AIRS Hotline
U.S. EPA, Office of Air Quality
Planning and Standards (OAQPS)
Tel: (800) 334-2405

Hazardous Air Pollutants

Hazardous Air Pollutants

The Cumulative Exposure Project, conducted by EPA's Office of Policy, Economics and Innovation, estimated outdoor concentrations of 148 hazardous air pollutants for 1990. EPA used a computer dispersion model, the Assessment System for Population Exposure Nationwide (ASPEN), to estimate concentrations. ASPEN was developed as part of the Cumulative Exposure Project and expands on standard EPA models by including the capability to model a large number of pollutants across the entire continental United States. EPA combined ASPEN with an inventory of estimated 1990 hazardous air pollutant emissions, from both mobile and stationary sources, to produce the 1990 ambient concentration estimates. The model's estimates were generally consistent with the limited monitoring data available for hazardous air pollutants from 1990. More information is available at http://www.epa.gov/CumulativeExposure.

To create the measures in this report, we started by calculating an average ambient concentration for each hazardous air pollutant in each county in 1990. This county-level value was calculated by averaging together the ASPEN estimates for each of the census tracts within each county. Then we compared the ambient concentration of each pollutant in each county with health benchmark values. Benchmark values are drawn from the toxicological literature and represent varying levels of potential concern for public health. We then identified counties in which the estimated 1990 ambient concentration of any hazardous air pollutant was greater than the health benchmarks, and calculated the total number of children living in those counties.

Agency Contact:
Daniel Axelrad (axelrad.daniel@epa.gov)
U.S. EPA, Office of Policy, Economics and Innovation
Tel: (202) 566-2304

Indoor Air Pollution

Surveys on Radon Awareness and Environmental Tobacco Smoke Issues

In 1994 and 1996, EPA's Indoor Environments Division commissioned a commercial contractor, Survey Communications, Inc., to conduct surveys on radon awareness and environmental tobacco smoke issues. Approximately 31,000 households in the 50 states were contacted in 1994 and 1996. All interviews were conducted by telephone using a random digit dialing sampling methodology. Both the 1994 and the 1996 surveys asked whether the household included any children under the age of 6. In addition, they asked the following:

In the 1994 survey, 6,411 households had children under the age of 6. In the 1996 survey, 6,851 households had children under the age of 6. The percentages of homes with children under the age of six in which someone smokes, or in which someone smokes regularly, were obtained by crossing the question on children with the appropriate question on smoking in the household.

In 1999, EPA commissioned the Center for Survey Research and Analysis at the University of Connecticut to conduct a similar but much smaller survey. The results of this survey were based on 1,005 telephone interviews with respondents located in the contiguous 48 states, using a random digit dialing sampling methodology. The survey questions regarding smoking in the home were similar to the questions in the 1994 and 1996 surveys. In the 1999 there were 225 households with children 6 years of age or younger survey. Although the 1999 survey was substantially smaller than the 1994 and 1996 surveys, all three surveys were designed to produce nationally representative samples.


Drinking Water Contaminants

Safe Drinking Water Information System (SDWIS)

The Safe Drinking Water Information System (SDWIS) is the national regulatory compliance database for EPA's drinking water program. SDWIS includes information on the nation's 170,000 public water systems and data submitted by states and EPA regions in conformance with reporting requirements established by statute, regulation, and guidance.

EPA sets national standards for drinking water. These requirements take three forms: maximum contaminant levels (MCLs, the maximum level of a specific contaminant that can occur in drinking water), treatment techniques (specific methods that facilities must follow to remove certain contaminants), and monitoring and reporting requirements (schedules that utilities must follow to report testing results). States report any violations of these three types of standards to EPA.

Water systems must monitor for contaminant levels on fixed schedules and report to EPA when a maximum contaminant level has been exceeded. States also must report when systems fail to meet specified treatment techniques. More information about the maximum contaminant levels can be found online at http://www.epa.gov/OGWDW/mcl.html.

EPA sets minimum monitoring schedules that drinking water systems must follow. These minimum reporting schedules (systems may monitor more frequently) vary by the size of the water system as well as by contaminant. Some contaminants are monitored daily, others need to be checked far less frequently (every nine years is the longest monitoring cycle). For example, at a minimum, drinking water systems will monitor continuously for turbidity, monthly for bacteria, and once every four years for radionuclides. A monitoring and reporting violation occurs when the system did not perform the required testing, take adequate samples, or report a violation as required. Only major monitoring and reporting violations are used in this report.

SDWIS includes the total population served by each public water system and the state in which the public water system resides. However, SDWIS does not include the number of children served. The numbers of children served by the public water systems were estimated by determining the ratio of children in the state in which the public water system resides and multiplying the ratio by the number of people served by that public water system.

For additional information see the EPA's SDWIS website at
http://www.epa.gov/safewa ter/sdwisfed/sdwis.htm.

Agency Contact:
Abraham Siegel (siegel.abraham@epa.gov)
U.S. EPA Office of Ground Water and Drinking Water
Tel: (202) 564-4637

Pesticide Residues in Foods

Pesticide Data Program

In 1991, the U.S. Department of Agriculture (USDA) was charged with implementing a program to collect data on pesticide residues in food. The Pesticide Data Program (PDP) has been in operation since 1991 and has published its findings for calendar years 1991 through 1998. PDP continues to focus on the National Academy of Sciences' 1993 recommendation that pesticide residue monitoring programs target foods that are highly consumed by children, and that the analytical testing methods used in these monitoring efforts should be standardized, validated, and subject to strict quality control and quality assurance programs. Consequently, since 1994 PDP has modified its commodity testing profile to include not only fresh fruits and vegetables, but also canned and frozen fruits and vegetables, fruit juices, whole milk, wheat, soybeans, oats, corn syrup, peanut butter, and poultry. In 1998, PDP collected and analyzed a total of 8,500 food samples, including approximately 7,000 samples of fruits and vegetables. More information is available at http://www.ams.usda.gov: 80/science/pdp/index.htm. exit EPA

Each sample of food tested in the PDP is analyzed to determine whether the residues of a variety of different pesticides are present. For the pesticide measure in this report, we assigned each sample to one of three groups: (1) no pesticides present at detectable levels; (2) one pesticide present at detectable levels; and (3) two or more pesticides present at detectable levels. The numbers of samples with one pesticide and the numbers with multiple pesticides were totaled for each year 1994-98 and calculated as a percentage of the total number of samples in each year.

Agency Contact:
Martha Lamont (Martha.Lamont@usda.gov)
USDA, Agricultural Marketing Service
Tel: (703) 330-2300

Land Contaminants

Superfund NPL Assessment Program Database

The Superfund NPL Assessment Program (SNAP) is a relational database system containing data for proposed, final, and deleted National Priorities List (NPL) sites. The majority of the information contained in SNAP is the data that support the NPL listing of sites; e.g., Hazard Ranking System (HRS) scoring factors, site narratives, site characteristics, contaminants, locational information, proposed and final Federal Register dates and citations, etc. For the most part, the data contained in SNAP are a snapshot at the time of NPL proposal and listing, although SNAP also contains a minimal amount of data (date and status) on Construction Completions, partial deletions, and deletions. This information allows SNAP to give an accurate overall picture of the status of the NPL on a real-time basis. All of the data contained in SNAP are publicly available information.

The measures presented in this report made use of SNAP's information on each county in which an NPL site is found and on the status of the NPL site-i.e., date proposed for the NPL, date of final listing, date of Construction Completion, and date of deletion. We then assembled data snapshots of the sites that were on the NPL on September 30 of 1990, 1992, 1994, 1996, and 1998. In addition, a snapshot for August 2000 (when information was obtained from SNAP for the purpose of assembling these measures) was assembled. We developed two measures for each of these dates. The first measure was based on all sites with either proposed or final listing on the NPL as of the target date, but excluding those sites deleted from the NPL on or before the target date. The second measure differed from the first in that sites that had reached Construction Completion (but were not yet deleted from the NPL) also were excluded. The counties with Superfund sites then were identified using the site location information in SNAP.

Agency Contact:
Terry Jeng (jeng.terry@epa.gov)
U.S. EPA Office of Emergency and Remedial Response
Tel: (703) 603-8852

Concentrations of Lead in Blood

National Health and Nutrition Examination Survey

Data on children's blood lead levels were obtained from the National Health and Nutrition Examination Surveys (NHANES) II and III, conducted by the National Center for Health Statistics. The survey is designed to assess the health and nutritional status of the non-institutionalized civilian population of the United States, aged 2 months and older. NHANES collects data through both direct physical examinations and interviews, using a complex multi-stage, stratified, clustered sampling design. Interviewers obtain information on personal and demographic characteristics, including age, household income, and race and ethnicity by self-reporting or as reported by an informant. The first survey, NHANES I, was conducted during the periods 1971-1974 and 1974-1975; NHANES II covered the period 1976-1980; and NHANES III covered the period 1988-1994. Only NHANES II and III, however, contain data on blood lead levels. Descriptions of the survey design, the methods used in estimation, and the general qualifications of the data are presented in the following:

The percentage of children with blood lead levels greater than 10µg/dL is influenced by the proportion of nonresponses within each category. Families with incomes below the poverty level had a lower response rate than families with incomes at or above the poverty level. The percentages are thus the best estimates available, but contain some error

NHANES Website: www.cdc.gov/nchs/nhanes.htm exit EPA

Agency Contact:
Clifford Johnson (clj1@cdc.gov)
National Center for Health Statistics
Tel: (301) 45-4292

Asthma and Chronic Bronchitis

National Health Interview Survey

Data on the prevalence of asthma and bronchitis are from the National Health Interview Survey (NHIS), a continuing nationwide sample survey of the civilian non-institutionalized population in which data are collected by personal household interviews. Interviewers obtain information on personal and demographic characteristics, including race and ethnicity, by self-reporting or as reported by an informant. Investigators also collect data about illnesses, injuries, impairments, chronic conditions, activity limitation caused by chronic conditions, utilization of health services, and other health topics. For most health topics, the survey collects data over an entire year.

The NHIS sample includes an over-sample of Black and Hispanic persons and is designed to allow the development of national estimates of health conditions, health service utilization, and health problems of the U.S. civilian non-institutionalized population. Over the years, the response rate for the ongoing part of the survey has run between 94 and 98 percent. In 1997, interviewers collected information on 36,116 persons, including 14,290 children.

Descriptions of the survey design, the methods used in estimation, and the general qualifications of the data are presented in the following:

NHIS Website: http://www.cdc.gov/nchs/nhis.htm exit EPA

Agency Contact:
For information on activity limitations and general health status:
Laura Montgomery (lem3@cdc.gov)
National Center for Health Statistics
Tel: (301) 436-3650

National Hospital Discharge Survey

Data on asthma hospitalizations were obtained from the National Hospital Discharge Survey (NHDS). The NHDS is a national probability survey designed to meet the need for information on characteristics of in-patients discharged from non-federal short-stay hospitals in the United States. The NHDS collects data from a sample of approximately 270,000 in-patient records acquired from a national sample of approximately 500 hospitals. Only hospitals with an average length of stay of fewer than 30 days for all patients, general hospitals, or children's general hospitals are included in the survey. Federal, military, and Department of Veterans Affairs hospitals, as well as hospital units of institutions (such as prison hospitals), and hospitals with fewer than six beds staffed for patient use, are excluded. Data from the NHDS are available annually.

NHDS Website: http://www.cdc.gov/ nchs/about/major/hdasd/nhdsdes.htm exit EPA

Agency contact:
Hospital Care Statistics Branch
National Center for Health Statistics
Tel: (301) 458-4321

Childhood Cancer

Surveillance, Epidemiology and End Results Program

The population-based data used for incidence of cancer are from the Surveillance, Epidemiology and End Results (SEER) Program of the National Cancer Institute (NCI). Information from five states (Connecticut, Hawaii, Iowa, New Mexico, and Utah) and five metropolitan areas (Atlanta, Georgia; Detroit, Michigan; Los Angeles, California; San Francisco-Oakland, California; and Seattle-Puget Sound, Washington) accounting for approximately 14 percent of the United States' population are included. The participating regions were selected primarily for their ability to operate and maintain a population-based cancer reporting system and for their epidemiologically significant population subgroups. With respect to selected demographic and epidemiologic factors, they are, when combined, a reasonably representative subset of the U.S. population.

The mortality data for all cancer deaths among children in the United States are from data based on underlying cause of death from the National Vital Statistics System, administered by the National Center for Health Statistics. Mortality data are obtained by NCI and provided for all causes of cancer.

All rates are age-adjusted to the 1970 U.S. standard population.

SEER Website: http://seer.cancer.gov exit EPA

Agency Contact:
Surveillance, Epidemiology, and End Results Program
National Cancer Institute

Child Population Data

U.S. Census County-Level Data

County population estimates are created by the U.S. Census Bureau starting with the most recent decennial census figure (April 1, 1990) and updating that figure with information on births, deaths, domestic migration (in/out flows with other counties in the United States), and international migration (in/out flows with other countries) that have occurred between the census date and the date of the population estimate.

The U.S. Census Bureau Population by Race and Age data are estimates of the resident population of the counties in the United States, by age (ages 0 to 84, 85 and over), sex (male, female), race (White; Black; American Indian, Eskimo and Aleut; Asian and Pacific Islander) for July 1 of each year from 1990 to 1998. A complete description of the population estimation methodology can be found on the Census Bureau's Methodology for Estimates of State and County Total Population website at http://www.census.gov /population/methods/stco99.txt exit EPA and on the Census Bureau's Methodology for Estimating County Population by Age and Race website at http://ww w.census.gov/population/estimates/county/casrh_doc.txt. exit EPA

Agency Contact:
U.S. Census Bureau
Population Estimates Branch
Tel: (301) 457-2385
http://eire.census.gov/po pest/data/counties.php exit EPA

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