ATSDR in Partnership With Nebraska
The Agency for Toxic Substances and Disease Registry (ATSDR) is the lead
public health agency responsible for implementing the health-related provisions
of the Comprehensive Environmental Response, Compensation, and Liability Act of
1980 (CERCLA). ATSDR is an Atlanta-based federal agency with more than 400
employees and a budget for 2004 of approximately $73 million. ATSDR assesses the
presence and nature of health hazards at specific Superfund sites, helps to
prevent or reduce further exposure and illnesses resulting from those hazards,
and expands the knowledge base about the health effects of exposure to hazardous
substances. ATSDR works closely with state agencies to carry out its mission to
serve the public by using the best science, taking responsive public health
actions, and providing trusted health information to prevent harmful exposures
and disease related to toxic substances. ATSDR provides funding and technical
assistance to states and other partners through cooperative agreements and
grants to identify and evaluate environmental health threats to communities.
These resources enable state and local health departments and other grantees to
further investigate environmental health concerns and to educate communities. In
fiscal years 1989-2004, ATSDR awarded more than $830,000
in direct funds and services to Nebraska for financial support
of specific environmental health activities. In addition to direct funds and
services, ATSDR provides technical and administrative guidance for
state-conducted site activities.
ATSDR Site-Specific Activities
Public Health Assessment-Related Activities
One of ATSDR's important mandates is to conduct
public health
assessments of all National Priorities List (NPL) sites and of other
sites where a significant threat to public health might exist. A public health
assessment is a written, comprehensive evaluation of available data and
information about the release of hazardous substances into the environment in a
specific geographic area. Such releases are assessed for past, current, or
future impact on public health. ATSDR, in collaboration with public health and
environmental officials from
Nebraska, has conducted
13
public health assessments in the state, including the following recent example.
Omaha Lead Site—In June 2004, ATSDR
released a public health assessment for the Omaha Lead site
for public review and comment. The Omaha Lead site includes residential
properties, child-care facilities, schools, and other properties in the city
of Omaha. These properties have been contaminated with lead from air
emissions from lead-refining operations beginning in the 1870s and
continuing until 1997, and from other sources, including lead-contaminated
soil and lead-based paint.
ATSDR reviewed blood lead testing results for approximately 12,800 children,
soil lead data for approximately 15,000 properties, and various exposure
scenarios. ATSDR concluded that ongoing lead exposure to children 6 years
and younger living in or near the site puts them at risk for lead-related
health effects.
From July 2000 through August 2002, nearly 300 (9.7%) children living in or
near the site had blood lead levels of 10 micrograms per deciliter (µg/dL)
or greater, compared with 2.0% for Nebraska and 3.1% for the United States
in 2001. The majority of these children had blood lead levels between 10 and
40 µg/dL and may be at risk for decreases in IQ, slightly impaired hearing
and growth, and problems metabolizing vitamin D.
Children living in the site area are exposed to two major sources of
lead-lead-based paint and past emissions from lead-refining operations. More
than 60% of the homes in the site area likely have lead-based paint. In more
than 40% of the properties tested, lead levels in at least one sample were
above 400 parts per million (ppm), the U.S. Environmental Protection Agency
(EPA) time-critical-removal action level. The mean soil lead level for the
Omaha Lead site area was 437 ppm.
The public health assessment recommended that county, state, and federal
agencies involved with the site develop a lead-hazards plan to increase
public knowledge about lead hazards, promote primary prevention activities,
and promote and facilitate yearly blood lead testing for all children 6
years and younger living in or near the site. Such testing will increase the
likelihood of identifying children being exposed and will allow timely
interventions such as mitigation of lead-based paint and cleanup of
contaminated soil.
A
health consultation is a written or oral response from ATSDR
to a specific request for information about health risks related to a specific
site, chemical release, or hazardous material. A health consultation is a more
limited response than a public health assessment.
One hundred twelve
health consultations have been conducted at
51 sites in
Nebraska, including the following recent example.
National Asbestos Exposure Review Site—The
Western Mineral Products Company site in Omaha is
among 28 Phase I sites in ATSDR's National Asbestos Exposure Review (NAER)
being conducted with other federal, state, and local environmental and
public health agencies. NAER examines more than 200 U.S. sites that received
asbestos-contaminated vermiculite ore mined in Libby, Montana, from the
early 1920s until 1990. The 28 Phase 1 sites, which received 80% of the
vermiculited mined in Libby in 1964-1980, may have received vermiculite from
Libby during the years the mine operated. All Phase 1 sites ceased
processing the vermiculite by the early 1990s: this site ceased operations
in 1989.
ATSDR is working closely with EPA and state health partners to determine
whether a hazard to public health exists at any of the NAER sites.
An
exposure investigation collects information about specific
human exposures through biologic sampling, personal monitoring, related
environmental assessment, and exposure-dose reconstruction. Following is an
example of an exposure investigation conducted by ATSDR in
Nebraska.
Dakota City/South Sioux City—Beginning in
1996, citizens in Dakota City and South Sioux City
voiced concerns that hydrogen sulfide pollution in the community might be
causing health problems. In August 1996, a community organization,
Citizens Promoting Environmental Stewardship, asked ATSDR to
conduct a community exposure investigation to determine whether ambient and
indoor air levels of hydrogen sulfide threatened their health. Residents
were concerned about odors; respiratory problems, including asthma; and
neurologic symptoms (headache, excessive fatigue, limb pain). Since 1996,
ATSDR has worked closely with staff from other agencies such as the EPA
Region 7 office, Nebraska Department of Environmental Quality,
Nebraska Department of Health and Human Services, Dakota
County Health Department, and local elected officials.
To evaluate exposure, ATSDR, in collaboration with EPA, conducted
independent hydrogen sulfide air monitoring in six Dakota City residences
and at ambient air locations between April and June 1997. As part of this
investigation, Nebraska officials identified 13 potential sources of
hydrogen sulfide in the community, including a large food-processing plant
(with a tannery and a municipal sewer vent) and one of the largest
meat-processing plants (with a tannery and uncovered sludge lagoons).
Air-data findings and residents' symptoms were consistent with symptoms
associated with hydrogen sulfide exposure. ATSDR concluded that indoor and
outdoor levels of hydrogen sulfide and other sulfur compounds posed a threat
to public health. Now that the sludge lagoons are covered and other emission
controls are in place, ATSDR is again conducting ambient and indoor air
monitoring.
Health Education and Community Activities
As part of its ongoing outreach activities in affected communities, ATSDR
proactively involves communities in identifying their health concerns and
developing actions to address them. An example of this type of involvement in
Nebraska is the health education plan for the Omaha Lead site being
developed in conjunction with the
Douglas County Health Department,
Nebraska Department of Environmental Quality,
Nebraska
Cooperative Extension Service,
Nebraska Department of Health
and Human Services, and EPA.
Health Studies
Health studies are investigations to determine the relations between exposures
to hazardous substances and adverse health effects. They also define health
problems that require further investigation through, for example, health
surveillance or an epidemiologic study. Following are examples of health studies
that ATSDR conducted or supported in
Nebraska.
Cornhusker Army Ammunition Plant—In fall
1993, a symptom- and disease-prevalence study was conducted to assess the
health status of people living near the Cornhusker Army Ammunition Plant and
the health status of people living in a similar comparison area. Principal
contaminants were neurotoxic agents. Self-reported prevalence of illnesses
and symptoms were measured and biomedical testing was conducted to look for
evidence of organ damage or kidney, liver, or immune-system dysfunction.
Questionnaire information and biologic specimens (urine and blood) were
collected from 300 participants in the target and comparison areas. A subset
of the study population was administered a battery of neurobehavioral tests.
No differences were found between the target population levels and
established reference levels. No statistical differences existed between
target and comparison groups for any of the six functional groups of
neurobehavioral tests. The final report was published in September 1996.
Dakota City/South Sioux City—In response to community
health concerns about exposure to hydrogen sulfide air pollution in
Dakota City and South Sioux City, ATSDR conducted
a health investigation using neurobehavioral tests to measure possible
nervous-system toxicity. The purpose of the investigation was to evaluate
whether persons exposed to hydrogen sulfide had poorer neurobehavioral
functioning when compared with persons who were not exposed.
Records of 335 participants (171 target and 164 comparison) were analyzed.
Results of neurobehavioral tests for both groups were generally similar. For
the adjusted analysis, age was an important covariate of test performance,
followed by educational level and test language (English or Spanish).
The target group performed better on 17 tests and poorer on 7 tests, but the
magnitude of these differences was small. No difference was observed in
performance on four tests for both groups. Exposure to hydrogen sulfide was
associated with marginally poorer performance for a test of memory and a
test of strength. However, these differences were not statistically
significant. Deficits in overall neurobehavioral performance were not
associated with exposure to hydrogen sulfide in this study.
Study results were published in U.S. peer-reviewed professional journals in
2003-2004. Study findings will help epidemiologists and toxicologists assess
health risks for hydrogen sulfide exposures.
Resource Materials
ATSDR develops materials for public health professionals and medical care
providers to use to assess the public health impacts of chemical exposures.
These resources are available in print, on the ATSDR Web site, and on CD-ROM.
For example, medical management guidelines are available for acute chemical
exposures to more than 50 chemicals. These guidelines were designed to aid
emergency department physicians and other emergency health care professionals,
such as first responders, who manage acute exposures resulting from chemical
incidents. ATSDR's toxicological profiles comprehensively describe health
effects; pathways of human exposure; and the behavior of more than 250 hazardous
substances in air, soil, and water at hazardous waste sites. The toxicological
profiles primarily are used as a comprehensive resource by health professionals
at all levels. These profiles have been sent to requesters, including
representatives of federal, state, and local health and environmental
departments; academic institutions; private industries; and nonprofit
organizations in
Nebraska. ATSDR also has developed extensive
resources for community members.
July 2004