Background
The Agency for Toxic Substances and Disease Registry’s
(ATSDR) congressionally mandated Substance-Specific Applied Research Program
(SSARP) currently consists of a research agenda for 60 top hazardous substances
that is being accomplished through successful partnerships with other federal
agencies, universities, and industry groups.
Legislative Mandate
The Comprehensive Environmental Response, Compensation,
and Liability Act of 1980 (CERCLA, or “Superfund” legislation) requires ATSDR to
carry out the following activities:
- Develop, jointly with the U.S. Environmental Protection Agency
(EPA), a priority list of hazardous substances found at waste
sites on EPA’s
National Priorities List (NPL).
- Prepare toxicological profiles
for hazardous substances found at NPL sites.
- Assure, in cooperation with the National Toxicology Program
(NTP), the initiation of a research program to address
identified data needs associated with the toxic substances,
i.e., SSARP.
Program Objectives
- Address the substance-specific information needs of the public
and scientific community.
- Supply information necessary to improve the database used to
conduct comprehensive public health assessments of populations
living near hazardous waste sites.
- Establish linkages between levels of contaminants in the
environment and levels in human tissues and organs that are
associated with adverse health effects.
Program Activities and Status
- Developed a “Decision Guide” in 1989 for determining research
priorities for hazardous substances found at waste sites and in
the environment.
- Established the Tri-agency Superfund Applied Research
Committee (TASARC) in 1991 to:
- Advise ATSDR on assigning priorities for mechanisms to
address research needs.
- Coordinate knowledge of research activities to avoid
duplication of research in other programs and under other
authorities.
- Advise ATSDR on issues of science related to
substance-specific research needs.
- Maintain a scheduled forum that provides an overall review
of SSARP.
- Established a research agenda in 1991 for an initial 38
hazardous substances - aldrin/dieldrin, arsenic, benzene,
beryllium, cadmium, carbon tetrachloride, chloroethane,
chloroform, chromium, cyanide, p,pðÀ-DDT, DDE, DDD,
di(2-ethylhexyl) phthalate, lead, mercury, methylene chloride,
nickel, polychlorinated biphenyl compounds (PCBs), polycyclic
aromatic hydrocarbons (PAHs), which include 15 substances,
selenium, tetrachloroethylene, toluene, trichloroethylene, vinyl
chloride, and zinc. Comments from the public were invited.
- Expanded the SSARP in 1997 by identifying research needs for
12 additional substances (chlordane,
1,2-dibromo-3-chloropropane, di-n-butyl phthalate, disulfoton,
endrin, endosulfan, heptachlor, hexachlorobutadiene,
hexachlorocyclohexane, manganese, methoxychlor, and toxaphene).
- Announced research needs in 2003 for 10 additional substances
(asbestos, benzidine, chlorinated dibenzo-p-dioxins,
1,2-dibromoethane, 1,2-dichloroethane, 1,1-dichloroethene,
ethylbenzene, pentachlorophenol, 1,1,2,2,-tetrachloroethane, and
total xylenes).
- Identified key mechanisms, with the oversight of TASARC, for
filling research
needs, including industry testing as a result of EPA
rule-making, voluntary industry testing (studies conducted by
industry groups at no expense to ATSDR), NTP testing, and direct
ATSDR-supported testing, including university-based research
through a cooperative agreement with the
Minority Health Professions Foundation (MHPF)
.
- To date, of 263 research needs identified for 60 substances,
62 research needs have been filled, and an additional 68 are
currently being addressed through various mechanisms.
Examples of Research Findings
- Lower chlorinated Aroclors (commercial polychlorinated
biphenyl [PCB] mixtures) (e.g., Aroclor 1016 and Aroclor 1242),
previously thought to be less toxic, are capable of producing
tumors in rats. Subsequently, EPA used the data from this study
to revise its cancer slope factor for PCBs.
- Exposure to benzo(a)pyrene (BaP) may adversely affect
reproductive health. BaP and its break-down products accumulate
in the testes and ovaries of animals exposed to BaP by ingestion
or inhalation. Pathological changes were observed in the testes
of male animals exposed to BaP, as well as a dose-dependent
decrease in the number of active sperm.
- Developed a new ATSDR health guidance value (Minimal
Risk Level) of 0.2 mg/kg/day for methylene chloride for
short-term exposure via the oral route.
- Consumption of water containing large amounts of methylene
chloride (approximately 600-6000 mg of methylene chloride per
liter of water) may result in adverse health effects on the
central nervous system, liver, and the development of newborns.
- Infants may be at risk for neurobehavioral effects from
exposure to maternal blood lead levels that are less than 10
µg/dL. These results among African American subjects corroborate
findings in other populations on the effects of low-level,
prenatal lead exposures.
- Lead accumulated preferentially in the brain of young animals
exposed to blood lead levels that are less than 5 µg/dL. This
provides biological evidence that even low levels of lead can
reach the brain and may cause adverse health effects during
early developmental stages.
- Hydroxylated metabolites of PCBs, which are considered to be
strong indicators of naturally occurring aerobic biodegradation,
were detected in sediment samples collected from
PCB-contaminated sites in the upper Hudson River.
Program Impact
The ATSDR SSARP, to date, has accomplished the following:
- Filled 62 research needs for populations potentially exposed
to hazardous environmental substances.
- Demonstrated the effectiveness of successful partnerships with
other federal agencies, universities, and industry groups in
filling critical public health
research
needs.
- Filled 19 public health research needs through
university-based research via an agreement with the
MHPF .
- Addressed 18 research needs for 8 substances using an
EPA/ATSDR test rule currently under development.
- Established Memoranda of Understanding with four private
sector organizations (American Chemistry Council, Electric Power
Research Institute, Inc., General Electric Company, and
Halogenated Solvents Industry Alliance, Inc.). These industry
groups are conducting studies to fill at least 16 research needs
associated with five substances at no expense to the agency,
resulting in a savings of about $10 million in research costs to
ATSDR.
Future Directions
Through the SSARP, ATSDR plans to broaden efforts to fill
research needs through outreach to a wider range of potential federal and
private-sector partners, including international organizations.
Selected References
Agency for Toxic Substances and Disease Registry.
Decision guide for identifying substance-specific data needs related to
toxicological profiles; Notice. 1989. Fed Regist 54: 37618-37634.
Agency for Toxic Substances and Disease
Registry. Announcement of final priority data needs for 38 hazardous
substances. 1992. Fed Regist 57: 54150-54159.
Agency for Toxic Substances and Disease
Registry. Announcement of final priority data needs for 12 priority
hazardous substances and call for voluntary research proposals.
1997. Fed Regist 62: 40820-40828.
Agency for Toxic Substances and Disease
Registry. Update on the status of the Superfund Substance-Specific
Applied Research Program. 2002. Fed Regist 67: 4836-4854.
Agency for Toxic Substances and Disease
Registry. Announcement of final priority data needs for 10 priority
hazardous substances. 2003. Fed Regist 68: 22704-22709.
Archibong AE, Inyang F, Ramesh A, et al.
2002. Alteration of pregnancy related hormones and fetal survival in
F-344 rats exposed by inhalation to benzo(a)pyrene. Reprod Toxicol
16(6):801-808.
Areola OO, Williams-Johnson M, Jadhav, AL.
1999. Relationship between lead accumulation in blood and soft
tissues of rats subchronically exposed to low levels of lead. Toxic
Subst Mech 18:1-13.
Emory E, Pattillo R, Archibold E, et al.
1999. Neurobehavioral effects of low level lead exposure in human
neonates. Am J Obstet Gynecol: 181(1):S2-11.
Emory E, Ansari Z, Pattillo R, et al. 2003.
Maternal blood lead effects on infant intelligence at age 7 months.
Am J Obstet Gynecol: 188(4):S26-32.
General Electric Company. An assessment of
the chronic toxicity and oncogenicity of Aroclors 1016, 1242, 1254,
and 1260 administered in diet to rats. Final report (February 1997).
Available by contacting the Division of Toxicology and Environmental
Medicine, ATSDR.
General Electric Company. Metabolite
detection as a tool for the determination of naturally occurring
aerobic PCB biodegradation. Final report (May 14, 1999). Available
by contacting the Division of Toxicology and Environmental Medicine, ATSDR.
Halogenated Solvents Industry Alliance, Inc.
Addressing priority data needs for methylene chloride with
physiologically based pharmacokinetic modeling. Final report
(February 4, 1997). Available by contacting the Division of
Toxicology and Environmental Medicine, ATSDR.
Inyang F, Ramesh A, Kopsombut P, et al. 2003.
Disruption of testicular steroidogenesis and epdidymal function by
inhaled benzo(a)pyrene. Reprod Toxicol 17(5):527-537.
Jadhav AL and Areola OO. 1997. Alteration in
acquisition and pattern of responding in rats subchronically exposed
to low levels of lead. Res Commun Biol Psychol Psych 22(1&2):11-24.
Ramesh A, Hood DB, Inyang F, et al. 2002.
Comparative metabolism, bioavailability and toxicokinetics of
benzo(a)pyrene in rats after acute oral, inhalation, and intravenous
administration. PAC 22:969-980.
Ramesh A, Inyang F, Hood DB, et al. 2001.
Metabolism, bioavailability, and toxicokinetics of benzo(a)pyrene in
F-344 rats following oral administration. Exp Toxicol Pathol
53:275-290.
Stevens, Y-W, Williams-Johnson, MM, De Rosa,
CT, et al. 2002. Findings and accomplishments of ATSDR’s
Superfund-mandated substance-specific applied research program. Int
J Hyg Environ Health 205: 29-39.
Where can I get more information?
For more information, contact
Agency for Toxic Substances and Disease Registry
Division of Toxicology and Environmental Medicine
1600 Clifton Road NE, Mailstop F-32
Atlanta, GA 30333
Phone: 1-800-CDC-INFO • 888-232-6348 (TTY)
Email: cdcinfo@cdc.gov
This page was updated on
10/17/2008