A-92-46
V-B-1
& EPA
-p.ited Stales
Environmental Protection
•\iencv
Office ot Air Quality
Planning and Standards
Research Triangle Park, NC 27711
EPA-453/R-93-039
November 1993
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GUIDANCE FOR REVIEW OF
HIGH RISK POINT SOURCES
UNDER SECTION 112 OF THE
1990 CLEAN AIR ACT AMENDMENTS
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TABLE OF CONTENTS
FORWARD 3
1.0 HIGH RISK POINT SOURCE IN THE 1990 CLEAN AIR ACT
AMENDMENTS 4
1.1 Section 112(1) of the 1990 Clean Air Act
Amendments 4
1.2 Definitions: "High Risk", "Point Source" 4
1.3 Benefits of a HRPS Program 5
1.4 Organization of Document 7
2.0 DEVELOPING A HIGH RISK POINT SOURCE PROGRAM 8
2.1 Policy issues 8
2.1.1 Selecting Chemicals to Evaluate 8
2.1.2 Selecting Sources to Evaluate 9
2.1.3 Communicating About Risks 10
2.2 Technical Issues 11
2.2.1 Risk Assessment Methodologies 12
2.2.2 A Tiered Approach to Source Assessment . 12
2.2.3 Existing State Programs 13
REFERENCES 14
APPENDICES 15
APPENDIX 1 - HRPS PROGRAM 1985-1990 16
APPENDIX 2 - HUMAN TOXICITY INFORMATION 20
APPENDIX 3 - ECOLOGICAL RISK ASSESSMENT INFORMATION . . 25
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APPENDIX 4 - RISK COMMUNICATION INFORMATION 26
APPENDIX 5 - POLICY AND TECHNICAL GUIDANCE 28
APPENDIX 6 - HOW TO OBTAIN DOCUMENTS; HOW TO ACCESS
DATABASES 30
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FORWARD
The purpose of this High Risk Point Source (HRPS) guidance
is to outline policy and technical issues State, local, and
tribal agencies may wish to consider in developing a HRPS
program. The Environmental Protection Agency (EPA) envisions the
main audience to be agencies that do not already have an
established air toxics program, although all State/local/tribal
agencies may benefit from the information presented, and from the
resources listed in the appendices.
The EPA intends this document to be descriptive rather than
prescriptive; the document offers the reader suggestions and
resources regarding the development of a HRPS program. Further,
the Agency considers this to be a "living" document, and will
update it as necessary. Information in this document represents
a compilation of information from existing EPA documents, listed
in the reference section, which are available for those
interested in obtaining them.
This document, was developed to fulfill Congress's directive
concerning the HRPS program under section 112(1)(2), and is based
in large part on information and documentation that the EPA has
developed from its experience with the program since 1986. See
Senate Report 101-108, pages 193-194 (U.S. Senate Report, 1989)
which describes the Agency's efforts and support for the HRPS
program.
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1.0 HRPS IN THE 1990 CLEAN AIR ACT AMENDMENTS
1.1 Section 112(1) of the 1990 Clean Air Act Amendments
Section 112(1) of the 1990 Clean Air Act Amendments
(1990 Amendments) requires the EPA to establish guidance for
approval of State, local, or tribal air toxics control rules or
programs, where the parties voluntarily submit applications.
Agencies can receive program approval under this section if their
programs are at least as stringent as the applicable Federal
rules. Once approved, a State, local or tribal program (or
specified portion of the program) would be Federally enforceable
in lieu of the Federal program.
Section 112(1) of the 1990 Amendments also instructs the EPA
to develop guidance to assist these agencies in developing
programs for submission under section 112(1). Congress requires
the EPA to "include, as an element of the guidance, an optional
program begun in 1986 for the review of high-risk point sources
of air pollutants including, but not limited to, hazardous air
pollutants listed pursuant to subsection (b)."
(Section 112(1)(2)).
1.2 Definitions: "High Risk", "Point Source"
Under the previous HRPS program (see appendix 1), the EPA
did not define a "bright line" benchmark of what was to be called
"high risk". That definition was addressed on a case-by-case
basis. Under the 1990 program, the EPA suggests that agencies
consult section 112(f) of the 1990 Amendments for Congress's
guidance on acceptable risk levels under the residual risk
program. The language states that residual risk standards must
provide an ample margin of safety to protect public health, and
states that such standards must be promulgated for sources that
exceed a lifetime risk to the most exposed individual of one in
one million (section 112(f)(2)(A)). Further reading of this
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subsection may be of help to State local and tribal agencies in
defining "high risk".
With regard to the definition of "point source", the EPA
initially equated a point source with an industrial source .
(U.S. EPA, 1985). Beyond that, the Agency left the definition of
a point source up to the State or local agency. Under this new
version of the HRPS program, the EPA envisions the definition of
point source to be the equivalent of a stationary source as
defined in section 111 of the 1990 Amendments. Further, the EPA
envisions that a point source may be either a major source, or an
area source, as defined in sections 112(a)(l) and 112(a)(2), of
the 1990 Amendments.
1.3 Benefits of a HRPS Program
A high risk point source program can provide several
benefits to air pollution control agencies. First, a HRPS
program can help agencies evaluate and regulate sources which
will not be regulated in the near term via section 112(d) of the
1990 Amendments (e.g. Maximum Achievable Control Technology
(MACT) program). For example, a listed source category may
consist of major sources (those that emit greater than 10 tons
per year of one Hazardous Air Pollutant (HAP), or 25 tons per
year of a combination of HAP), and area sources (sources that
emits less than 10 or 25 tons per year). The major sources in
the category will be covered by a MACT standard, but the area
sources may not be regulated unless the EPA finds that such
sources warrant Federal regulation under section 112
(section 112(c)(3)) (see source category list 57 FR 31576, dated
July 16, 1992). In cases where the EPA determines that the area
source category does not warrant Federal regulation, the State,
local, or tribal agency may choose to assess a source to
determine whether it wishes to pursue regulation. This
evaluation could be conducted as part of a high risk point source
program.
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Secondly, an agency may wish to regulate sources under a
faster timetable than the Federal program. Section 112(e) of the
1990 Amendments requires the EPA to regulate source categories on
a specific schedule, either within 2, 4, 7, or 10 years after the
date of enactment (November 15, 1990). A State/municipality/
tribe may wish to apply the methodology offered in the HRPS
guidance to evaluate sources to determine whether early
regulation at the State level is warranted. Similarly,
States/locals/tribes may wish to evaluate sources in order to set
residual risk standards sooner than the Federal program.
Section 112(f) requires the EPA to address the issue of
residual risk within 8 years of the promulgation of a MACT
standard. A State, local, or tribal agency may wish to examine
the need for a residual risk examination before the 8 year
Federal analysis would be conducted.
Thirdly, agencies may wish to determine the risks associated
with sources of air toxics in response to public concern. For
example, members of the public may ask health-related questions
during operating permit hearings, or they may make general
inquiries as to the safety of ambient air.
A HRPS program can also increase equity in the environmental
arena by helping an agency address a source that will not be
regulated under the Federal program. For example, a State, local
or tribal agency could use a HRPS program to evaluate and
regulate a single source or limited number of sources that will
not be a source category to be regulated under the Federal
regulatory program.
Finally, the methodology and resources presented in the HRPS
guidance can add to the available tools that States, locals, and
tribes can use to evaluate the potential for adverse health
impacts and protect public health from local sources of toxic air
pollutants. In addition, exposure and risk information collected
from HRPS evaluations will be useful to other State, local, and
tribal agencies, and to the EPA as well.
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1.4 Organization of Document
The document begins with a discussion of policy issues: how
to determine what chemicals to assess; how to choose sources to
assess; and how to communicate program objectives and risks to
health. The document then briefly introduces the concept of risk
assessment; outlines a tiered methodology agencies may choose to
follow to determine whether the risk from a particular source (or
set of sources) is significant; and apprises the reader of
existing State programs that may be adaptable to other agencies
for use as HRPS programs. The appendices direct the reader to
appropriate EPA documents, other agency's documents, and selected
services. These documents and services may assist agencies in
evaluating health effects from potentially high risk point
sources.
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2.0 DEVELOPING A HIGH RISK POINT SOURCE PROGRAM
2.1 Policy issues
2.1.1 Selecting Chemicals to Evaluate
The first question to answer in developing up a HRPS program
might be, "What chemicals should the program include?". There
are at least three ways to answer this question. First, an
agency may wish to prepare a list of toxic air pollutants that
will be evaluated if emitted. Second, an agency may wish to
evaluate chemicals of concern on an ad hoc basis. Third, an
agency may wish to use a combination of these two approaches,
perhaps using a list to evaluate existing sources and the ad hoc
approach for new sources (EPA, 1990).
In preparing their own chemical list, a State/local/tribal
agency may wish to look to other existing lists of toxic air
pollutants. There are several Federal lists to examine,
including, but not limited to, the Hazardous Air Pollutant list
under section 112(b) of the 1990 Amendments, and the SARA 313
list (EPA, 1992a). Some States have existing chemical lists as
well. Names and addresses of State air toxics contacts can be
found in the annual Database Report on State, Local, and EPA Air
Toxics Activities, published by the National Air Toxics
Information Clearinghouse (NATICH) or by searching the NATICH
bulletin board on the EPA's Technology Transfer Network Bulletin
board (see Appendices 2 and 6).
In addition to looking at existing pollutant lists, an
agency may wish to consider other information, such as toxicity
and exposure information, in developing a chemical list. While
existing lists of chemicals may include a consideration of these
factors, each list was developed for a specific purpose, and may
have considered these parameters differently than a specific
State, local, or tribal agency would. For example, a chemical
may have been left off of the SARA 313 list because it was not
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used on a national scale. If sources under a State, local, or
tribal agency's jurisdiction emit a significant amount of this
chemical, the agency may want to include such a chemical on their
list, even though the national lists or other State lists do not.
The open-ended approach to choosing chemicals for a HRPS
program requires evaluating chemicals, as needed, to see if they
are candidates for such a program rather than looking to a
specific list for chemicals. An evaluation may include
considerations of the health effects of individual chemicals, the
expected occurrence of emissions, and environmental effects. For
resources to aid agencies in considering health effects one may
wish to look at the data sources in Appendices 2, and 3.
2d.2 Selecting Sources to Evaluate
In determining which specific sources to include in a high
risk point source program, an agency may wish to consider several
factors. An agency may wish to evaluate all sources that emit
chemicals on the established list, or that emit chemicals the
agency determines to be of concern. An agency may wish to look
to the source category list (57 FR 31576) that the EPA developed
under section 112, for a list of type of sources that emit
chemicals of concern (to the Federal program) and limit
evaluations to those sources. Some agencies may wish to make a
conscious decision about whether to include certain types of
sources in the HRPS program (for example, "non-traditional"
sources including waste-water treatment facilities arid hazardous
waste landfills). An agency may wish to consider the* number size
and type of these facilities, and determine the practicality of
evaluating and potentially regulating such sources, at least at
the beginning of a HRPS program. Similarly, some types of area
sources can collectively emit significant amounts of toxic air
pollutants (for example, dry cleaners, wood-stoves, and
fireplaces). Because of their large number, these sources may be
difficult to review on an individual basis. As such, an agency
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may want to evaluate whether these types of sources should be
included in a HRPS program (EPA, 1990). In determining which
sources to include in a HRPS program (and in determining what
chemicals to assess), an agency should carefully evaluate its
available resources to insure that the program can be
implemented.
2.1.3 Communicating About Risks
Any high risk point source program, in fact any air toxics
program, should include a conscious effort to effectively
communicate about risks. Environmental risk communication is a
specialized skill that all agencies, Federal, State, local, and
tribal, should develop. Communication on environmental issues is
distinctive in at least four ways. The first distinctive feature
involves the complexity of information. Environmental
communication involves many disciplines including toxicology,
statistics, economics, law, human behavior, engineering, and
business management. The second feature is the gap in technical
knowledge of the general public. Technical information is often
full of jargon, and discussions about technical processes may be
unintelligible to the public. The third distinctive feature is
the personal impact of the issues at stake. The air people
breathe is of course a deeply personal concern. The fourth
feature is the concept of relative risks. The distinction of
voluntary and involuntary risks is frequently a factor in
environmental communication (EPA, 1990). Appendix 4 includes a
partial list of available risk communication documents.
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2.2 Technical Issues
2.2.1 Risk Assessment Methodologies
The EPA envisions that the methods used to evaluate
potential high risk point sources would be based on the principle
of risk assessment. Risk assessment is the process of estimating
and characterizing the potential adverse health effects of human
exposure to environmental hazards. It generally includes four
steps: hazard identification? dose-response assessment; exposure
assessment, and risk characterization. Hazard identification is
a qualitative determination that exposure to a certain substance
can cause adverse health effects in humans. A dose-response
assessment quantifies the relationship between the dose of a
toxicant received and the effect incurred. This can take the
form of specific levels of concern such as an inhalation
reference concentration (RfC) or as a slope of a dose-response
curve such as often developed for carcinogens. Exposure
assessment is the process of measuring or estimating the level
(e.g., concentration in the air breathed or water ingested),
duration, and frequency of human exposure to a chemical. Risk
characterization is the final step which quantitatively estimates
the magnitude of the risk to human health, and discusses
uncertainty in the assessment (EPA, 1990). See appendix 2 for
further information regarding risk assessment.
The "tiered approach to source assessment" described below,
is essentially a screening method to estimate human exposure to
toxicants. This method is designed to estimate an ambient
concentration, in the air, of a chemical(s). Since this is a
screening procedure, this ambient concentration is considered as
the exposure. Once this exposure step is complete, the next step
is to determine whether the concentration of a specific chemical
(or chemicals) can cause an adverse health effect. This is done
by comparing the exposure concentration to an appropriate
"benchmark", that is, a quantitative characterization of the
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dose-response interaction of the chemical(s) (see appendix 2 for
sources of risk assessment information).
2.2.2 A Tiered Approach to Source Assessment
This portion of the document discusses a tiered approach to
assessing sources that may be high risk. The term "tiered" is
used because such an approach consists of different levels, or
tiers of analysis that can be completed, depending on need and
resources, where each tier increases in sophistication and
requirements needed to complete the analysis. Much of the
discussion in this section comes from the EPA document, A Tiered
Modeling Approach for Assessing the Risks Due to Sources of
Hazardous Air Pollutants (Tiered Approach) (EPA, 1992b).
Resource information related to this section can be found in
appendices 5, and 6.
Tier 1 is a simple screening method used to evaluate the
exposure potential of sources. It consists of a procedure in
which the user can estimate the off-site concentrations of a
toxic air pollutant without extensive knowledge regarding the
source, and without using a computer. Tier 1 requires the user
to have information on emission rates, stack heights, and
fencelines of a source1. The user performs the analysis by
using tables of look-up values to obtain the maximum off-site
ambient air concentration of the modeled source. These ambient
air concentrations are then compared to the appropriate benchmark
(see section 2.2.1) to assess the impact of the modeled source.
If the predicted screening impacts are above what an agency
considers a level of concern, then the user may want to proceed
to a higher tier to obtain more accurate results.
The second tier is a more sophisticated screening technique
which requires additional knowledge of the source being modeled,
1 Relatively conservative assumptions were made in the
generation of the look-up table.
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and requires the use of a computer program. Tier 2 is less
conservative than Tier 1. In the "Tiered Approach" referenced
above, Tier 2 is structured around the EPA's SCREEN model
(EPA, 1992b). It requires information beyond that of Tier 1, and
again results in the maximum off-site ambient concentration.
The third tier is a more detailed modeling exercise, using
more site-specific inputs than Tier 2, and the Industrial Source
Complex Long Term Model (ISCLT) (EPA, 1992b). Tier 3 also
identifies the maximum off-site concentrations, but requires more
information to execute and is less conservative than the previous
tiers.
Tier 4 incorporates the level of modeling used in Tier 3,
with population data, to estimate potential exposures to a
specific population. The EPA's Human Exposure Models
(HEM, HEM-II) can serve this purpose (see appendix 5), as they
combine dispersion modeling with population information, to more
specifically characterize exposure. Note that all tiers
represent screening analyses.
2.2.3 Existing State Programs
Agencies interested in pursuing a HRPS program should also
consult with State and local agencies for other approaches to
assessing potential high risk point sources. For example,
California requires that certain sources in the State assess
risks from specific toxics air pollutants in its "Hot Spots
Program" under California Assembly Bill 2588 (California Air
Pollution Control Officers Association, 1992). Interested
parties can search the NATICH bulletin board (see appendices 2,
and 6) for States that use risk assessment in assessing sources
of toxic air pollutants. Such programs might be either adapted
or used directly as high risk point source programs.
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REFERENCES
California Air Pollution Control Officers Association (CAPCOA),
1992. Air Toxics "Hot Spots" Program; Risk Assessment
Guidelines.
U.S. EPA, Office of Air Quality Planning and Standards, 1985.
A Strategy to Reduce Risks to Public Health from Air Toxics.
(reprint available through NATICH).
U.S. EPA, Office of Air Quality Planning and Standards, 1990.
Designing and Implementing an Air Toxics Control Program; A
Program Development Manual for State and Local Agencies.
EPA-450/2-90-012.
U.S. EPA, Office of Solid Waste and Emergency Response, 1992a.
Title III List of Lists; Consolidated List of Chemicals Subject
to Reporting Under the Emergency Planning and Rioht-to-Know Act.
EPA-560/4-92-001.
U.S. EPA, Office of Air Quality Planning and Standards, 1992b.
A Tiered Modeling Approach for Assessing the Risks Due to Sources
of Hazardous Air Pollutants. EPA-450/4-92-001
U.S. Senate Report 101-108, 1989. Report of the Committee on
Environment and Public Works to Accompany S. 1630.
101st Congress, First Session.
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APPENDICES
Appendix 1 -
Appendix 2 -
Appendix 3 -
Appendix 4 -
Appendix 5 -
Appendix 6 -
HRPS Program 1985 - 1990
Human Toxicity Information
Ecological Toxicity Information
Risk Communication Information
Technical Guidance Information
How to Obtain Documents; How to Access Databases
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APPENDIX 1 - HRPS PROGRAM 1985-1990
In 1985, the Environmental Protection Agency (EPA) developed
an air toxics strategy to control emissions of hazardous air
pollutants presenting the greatest risks to public health. The
strategy documented existing programs and identified needed
actions to address emissions from both routine and accidental
releases. One component of the strategy called for the
development of programs to assist State and local air pollution
control agencies in their efforts to evaluate and control some
types of routine emissions of air toxics. The strategy noted
that some toxic air pollutants are emitted in large amounts, in
several states, and that these types of emissions would be
controlled under section 112 of the Clean Air Act. However, the
EPA stated that some toxic air pollutant emissions may not be so
prevalent as to be a national problem, but may still account for
areas of high risk in some communities. Such emissions would not
support a national standard, but may require targeted action by
State or local agencies (EPA, 1985). Among the specific actions
the Agency decided to take as a result of this 1985 strategy, was
to initiate a partnership with State and local air pollution
control agencies to reduce public health risks from these
localized sources. One of these efforts came to be called the
High Risk Point Source (HRPS) Program.
In the process of determining whether sufficient information
was available to add pollutants to the list of hazardous air
pollutants and then promulgate emission standards, the EPA
determined that national regulation might not be required in all
cases if sufficient reductions could be accomplished at the State
and local level. As a result of this conclusion, the Agency
initiated a pilot program to refer information on a given
chemical to a State for evaluation, with the expectation of
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regulation at the State level1. This form of the program was
not continued due to criticism from public interest groups and
from States who argued that by simply "referring" a chemical to
the States for possible regulation, the EPA was abdicating its
responsibility to protect public health.
The next iteration of the HRPS program was called the
"promoted initiative program". Under this program, the EPA
committed grant money from section 105 of the Clean Air Act, to
States. These grants were to help States/locals further assess
sources that, based on screening studies, the EPA had identified
as potentially "high risk", but for which the risk was not high
enough to warrant federal regulation. The next year, 1987, the
EPA responded to a request from the States to broaden the program
so that States could submit grant applications to assess sources
that States identified as potential high risk point sources, in
addition to the those the EPA targeted. This broadened program
was termed the Promoted and State Initiative Program.
The goals of the Promoted and State Initiative program were
tos (1) assist State/local agencies in building the capability
to evaluate sources of potential health concern; (2) require
controls of toxic emissions where appropriate; and (3) obtain
documentation of results in order to distribute the information
to interested State and local agencies. The criteria for
selecting a source as a promoted initiative, included the
following. During evaluation of pollutants for possible listing
under section 112, the EPA conducted screening level risk
analyses of selected sources emitting the pollutants under study.
If the Agency identified a source or a limited number of sources
that posed a potential risk to human health, such sources were
identified by the Agency as possible high risk point £>ources, and
1 Because acrylonitrile was of concern for its cancer
causing potential, and, because it was emitted from a limited
number of sources in a limited number of states, it became the
first chemical addressed in the referral program.
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considered for the promoted initiative portion of the program.
The EPA and State(s) then typically entered into discussions
about possible funding of further source evaluation. For funding
to occur, the State needed to demonstrate a commitment by
conducting the evaluation itself and by preparing a report
summarizing the findings. For a proposal to be accepted into the
State initiative program the State needed to show that the study
was of national utility, that the State or local agency was a new
program participant with limited resources, that there was little
chance of overlap with ongoing Federal regulatory efforts, that
there was a high value relative to the cost, and that there was a
potential for high risk to the public. The final reports
summarized the results of the study, included a decision on
whether or not the State/local was going to regulate the
source(s), and provided the rationale for that decision.
The EPA funded the promoted and State initiative program
from 1986 to 1990, using money available under section 105 of the
Clean Air Act. Funding for this program stopped in 1990 by
mutual agreement between the EPA and the State and Territorial
Air Pollution Control Association (STAPPA). Reasons for
discontinuing the funding included: (1) the fact that many
States had developed air toxics programs (2) the availability of
other mechanisms to reduce toxic air emissions, (3) the need to
address higher priority air quality management with the available
limited funding. As of April 1992, the EPA funded 86 projects in
37 States, at a cost of 1.5 million dollars. Of the 86 projects,
49 were complete, 29 were ongoing, and eight had been dropped.
Of the 49 completed projects, EPA now has 42 submitted written
reports which are on file in the Office of Air Quality Planning
and Standards' (OAQPS) Control Technology Center (CTC), and are
disseminated to interested parties upon request
(see appendices 5 and 6). Of these completed reports, 23
quantified health effects, and 17 achieved emission reductions.
In addition, the EPA estimates that the HRPS program provided
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"seed money" to 10-15 States to improve their own developing air
toxics programs, enhanced Regional and Federal office
cooperation, and promoted future evaluation of, and monitoring of
sources by State and local agencies.
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APPENDIX 2 - HUMAN TOXICITY INFORMATION
EPA Sources
The following documents are prepared by the EPA's Office of
Environmental Effects Assessment (OHEA). See appendix 6 for how
to obtain documents.
J. Health Assessment Documents (HAD):
HAD are comprehensive evaluations of the known health data,
including carcinogenicity, mutagenicity, developmental and
reproductive effects, pharmacokinetics, and metabolism, from
exposure to particular chemicals. HAD are developed for the
OAQPS.
2. Health Effects Assessments (HEA)s
HEA are brief, quantitatively orientated, assessments of
relevant health effects data. HEA are prepared for the Office of
Emergency and Remedial Response (Superfund).
3. Health and Environmental Effects Documents (HEED):
HEED are summaries of the literature concerning health
hazards associated with environmental exposures to particular
chemicals. They are prepared for the Office of Solid Waste and
Emergency Response's (OSWER) Resource Conservation and Recovery
Act (RCRA) and Superfund programs. (Former documents are called
Health and Environmental Effects Profiles (HEEPs)).
4. Reportable Quantities Documents (RQCAR, RQTOX)
RQ documents are brief data summaries prepared for OSWER's
Comprehensive Environmental Response, Compensation, and Liability
ACT (CERCLA) program.
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5. Ambient Water Quality Criteria Documents (WQCD):
WQCD are prepared for the Office of Water and provide an
assessment of the potential risk of adverse effects of a
pollutant on human health and aquatic life.
6. Drinking Water Criteria Documents (DWCD):
DWCD are comprehensive health effects evaluations of data on
pharmacokinetics, human exposure, acute and chronic toxicity to
animals and humans/ epidemiology, and mechanisms of toxicity.
They are developed for the Office of Water (OW) (often developed
by the OW), and are available from NTIS, or from the OW.
Non-EPA sources; See appendix 6 for how to contact these
organizations.
1. American Conference of Governmental Industrial Hygienists
(ACGIH)
The ACGIH is a non-governmental agency that publishes
recommended occupational health limits called Threshold Limit
Values (TLV) in a yearly document called Threshold Limit Values
and Biological Indices. The ACGIH has also published the book,
Documentation of the Threshold Limit Values, which provides some
references as well as the reasoning behind the TLV. Both
documents are available from the ACGIH.
2, National Institute of Occupational Safety and Health
(NIOSH):
NIOSH publishes Recommended Exposure Levels (REL) which the
Occupational Safety and Health Administration, or the Mine Safety
and Health Administration (MSHA), may adopt as legal standards.
NIOSH publishes criteria documents that present critical
evaluations of relevant data on a chemical. The criteria
documents are available from NIOSH.
3. International Agency for Research on Cancer (IARC):
IARC is part of the World Health Organization (WHO), and
publishes monographs and updates on chemicals it has reviewed.
The monographs are referenced in RTECS (see below), and are
available at most university libraries.
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4. Agency for Toxic Substances and Disease Registry (ATSDR)
ATSDR publishes Toxicological Profiles which are used by the
Superfund program. The profiles contain toxicological and health
effects data and can be obtained through NTIS and university
libraries which contain federal repositories.
5. National Toxicology Program (NTP):
The NTP publishes National Cancer Institute (NCI)/NTP
technical reports on long-term cancer bioassays. These reports
can be obtained from the NTP.
Databases/Clearinghouses;
EPA sources;
1. Integrated Risk Information System (IRIS):
The IRIS database maintained by EPA's OHEA, contains agency
consensus positions on the potential adverse health effects of
approximately 500 substances. Information on IRIS can be
obtained from IRIS user support (see appendix 6).
2. National Air Toxics Information Clearinghouse (NATICH):
NATICH is an information service offered by the U.S. EPA in
conjunction with the State and Territorial Air Pollution Program
Administrators (STAPPA), and the Association of Local Air
Pollution Control Officials (ALAPCO), to support efforts at
controlling toxic air pollutants. NATICH collects, classifies
and disseminates air toxics information submitted by State and
local air agencies. It also publishes a bimonthly newsletter,
responds to telephone requests for specific information
((919) 541-0850) and publishes special reports on specific air
toxics issues. NATICH is also available on-line
(see appendix 6).
3. Air Risk Information Support Center (Air RISC)
Air RISC is an information service offered by the U.S. EPA
in cooperation with the State and Territorial Air Pollution
Program Administrators (STAPPA), and the Association of Local Air
Pollution Control Officials (ALAPCO), to support efforts at
controlling toxic air pollutants. Air RISC provides a hotline
service (919) 541-0888, and produces technical guidance on topics
involving health, exposure, and risk assessment issues related to
emissions of air toxics.
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Non-EPA sources; The following databases can be accessed through
the National Library of Medicine's Toxicology Data Network
(TOXNET) For information on how to access TOXNET, see appendix 6.
1. Registry of Toxic Effects of Chemical Substances (RTECS):
The RTECS database is built and maintained by NIOSH. It
contains toxic effects data on over 114,000 chemicals. Review of
these data however, is limited.
2. Hazardous Substances Data Bank (HSDB):
The HSDB contains peer-reviewed information on
4300 chemicals. Information includes: toxicity data; emergency
medical treatment; safety and handling; environmental fate;
potential exposure, and regulatory requirements.
3. Chemical Carcinogenesis Research Information System (CCRIS)s
CCRIS is sponsored by the National Cancer Institute, and
contains data derived from carcinogenicity, mutagenicity, tumor
promotion, and tumor inhibition studies.
4. GENE-TOXs
GENE-TOX is an EPA database which contains genetic
toxicology data on 3000+ chemicals. Data entered into GENE-TOX
has been expert-reviewed.
5. Developmental and Reproductive Toxicology Database/
Environmental Teratology Information Center Backfile
(DART/ETICBACK):
Both DART and ETICBACK contain citations to publications to
developmental toxicology. DART covers publication from 1989 to
the present; ETICBACK covers years prior to 1989. The EPA and
the National Institute of Environmental Health Sciences jointly
support these databases.
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6. Toxic Chemical Release Inventory (TRI)
TRI is a database which contains information on estimated
annual releases of toxic chemicals to the environment, and is
based on information reported to the EPA by emitting facilities.
TRI is built and maintained by the EPA and is authorized under
Section 313 of the Emergency Planning and Right-to-Know Act
(SARA 313).
Additional Information; The following information is available
through the National Library of Medicine's Toxicology Information
Program (TIP) (For information on how to access TIP, see
appendix 6):
TIP provides several online services as part of the National
Library of Medicine's Medical Literature Analysis and Retrieval
System (MEDLARS). It includes some of the databases in the
TOXNET system, and in addition:
Chemical Identification File (CHEMID)
Chemical Dictionary Online (CHEMLINE)
Toxicology Information Online/Toxicology Literature from
Special Sources (TOXLINE/TOXLIT)
Directory of Information Resources Online (DIRLINE)
Chemical Lists;
1. Title III List of Lists: Consolidated List of Chemicals
Subject to Reporting Under the Emergency Planning and Right-
to-Know Act. (EPA 560/4-92-011).
This document contains chemical lists as required by
Title III of the Superfund Amendments and Reauthorization Act of
1986 (SARA). Lists include: SARA Section 302 list of Extremely
Hazardous Substances, CERCLA Hazardous Substances list, SARA
Section 313 Toxic Chemicals list. It is available from NTIS.
2. Clean Air Act Amendments of 1990 (P.L. 101-546 104 Stat.
2399, November 15, 1990)
Section 112(b) of the 1990 Amendments contains the list of
hazardous air pollutants to be regulated.
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APPENDIX 3 - ECOLOGICAL RISK ASSESSMENT INFORMATION
The EPA's Office of Research and Development, and the EPA's
Risk Assessment Forum have developed the following documents
regarding ecological risk assessment. The documents are
available through CERI, or NTIS (see appendix 6).
Norton, Susan, B. et, al. 1992. A Framework for Ecological Risk
Assessment at the EPA. Environmental Toxicology and Chemistry.
11: 1663-1672.
U.S. EPA, Environmental Research Laboratory, Corvallis, Oregon.
1989. Ecological Assessment of Hazardous Waste Sites.
EPA/600/3-89/013
U.S. EPA, Risk Assessment Forum, 1991. Summary Report on Issues
in Ecological Risk Assessment. EPA/625/3-91-008.
U.S. EPA, Office of Research and Development, 1992. Evaluation
of Terrestrial Indicators for use in Ecological Assessment at
Hazardous Waste Sites. EPA/600/R-92/183.
U.S. EPA, Risk Assessment Forum, 1993. A Review of Ecological
Case Studies from a Risk Assessment Perspective.
EPA/630/R-92-005.
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APPENDIX 4 - RISK COMMUNICATION INFORMATION
Risk Communication Reports (Developed and available through the
EPA's Risk Communication Project 202-260-5606)
Bord, Richard, J., Donald J. Epp and Robert O'Connor. 1989.
Achieving Greater Consistency Between Subjective and Oblective
Risks. Pennsylvania State University. (EPA-230/11-89-071;
NTIS No. PB9-229832/AS).
Regan, Michael J., and William H. Desvousges. 1990.
Communicating Environmental Risks: A Guide to Practical
Evaluations. (EPA-230/01-91-001; NTIS No. PB91-168336)
Weinstein, Neil, D., Peter M. Sandman, and Nancy E. Roberts.
1989. Communicating Effectively about Risk Magnitudes.
(EPA 230/08-89-064; NTIS No. PB90-141292/AS)
Additional Risk Communication Publications;
American Chemical Society. 1988. Chemical Risk Communication.
Washington, DC. American Chemical Society.
Arkin, Elaine Bratic. 1989. Making Health Communication
Programs Work. National Cancer Institute, NIH.
Covello, Vincent T., David B. McCallum, Maria Pavlova (eds.)
1987. Effective Risk Communication. New York & London: Plenum
Press.
Covello, Vincent T., and Frederick W. Allen. 1988. Seven
Cardinal Rules of Risk Communication. Washington, DC. U.S. EPA.
Davies, J. Clarence, Vincent T. Covello and Frederick W. Allen
(eds.) 1987. Risk Communication; Proceedings of the National
Conference on Risk Communication. Washington, DC. The
Conservation Foundation.
Fischhoff, Baruch, S. Lichtenstein, Paul Slovic, S. Derby, R.
Keeney. 1981. Acceptable Risk. Cambridge, MA. Cambridge
University Press.
Fisher, Ann, Maria Pavlova, Vincent Covello (eds.) 1991.
Evaluation and Effective Risk Communication: Workshop
Proceedings (Interaqency Task Force on Environmental Cancer and
Heart and Luna Disease). Washington, DC. Interagency Task
Force.
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Hammond, P. Brett, and Rob Coppock (eds.) 1990. Valuing Health._
Risks, Costs, and Benefits for Environmental Decision Making -
Report of a Conference. Washington, DC. National Academy Press.
Hance, Billie Jo, Caron Chess and Peter M. Sandman. 1988
Improving Dialogue with Communities; A Risk Communication Manual
for Government. Washington, DC. U.S. EPA.
Johnson, Branden B. and Vincent T. Covello. 1987. The Social
and Cultural Construction of Risk. Dordrecht/Boston/
Lancaster/Tokyo. D. Reidel Publishing Company, Member Kluwer
Academic Publishing Group.
Krimsky, Sheldon, and Alonzo Plough. 1988. Environmental
Hazards Communicating Risks as a Social Process. Dover, MA.
Auburn House Publishing Co.
McCallum, David B., Sharon Lee Hammond, Louis A. Morris. 1990.
Public Knowledge and Perceptions of Chemical Risks in Six
Communities. Washington, DC. U.S. EPA.
National Research Council Commission/National Academy of Sciences
1989. Improving Risk Communication. Washington, DC. National
Academy Press.
Sandman, Peter, M. 1986. Explaining Environmental Risk.
Washington, DC. U.S. EPA.
U.S. EPA, 1990. Communicating Environmental Risks; A Guide to
Practical Evaluations. 230/01-91-001
U.S. EPA, Air Risk Information and Support Center, 1991. Air
Pollution and the Public; A Risk Communication Guide for State
and Local Agencies. (EPA 450/3-90-025)
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APPENDIX 5 - POLICY AND TECHNICAL GUIDANCE
The EPA has developed a number of models and related guidance
documents that can be used to estimate ambient impacts from toxic
air releases. In addition, the Agency has developed guidance for
State and local agencies regarding the development of Air Toxics
Programs, and risk assessment methodology guidance. The
following is a list of some of these documents. State and local
air pollution control agencies communicate directly with the EPA
regional offices for updated and relevant references. Computer
code for the models is available from the OAQPS, Technology
Transfer Network Bulletin Board System (see appendix 6). User's
guides and guidance documents may be obtained from NTIS, or CERI,
using the information listed below.
Policy and Modeling Guidance;
U.S. EPA, 1978. Guideline on Air Quality Models (Revised).
EPA-450/2-78-027R (NTIS No. PB 86-245248), and its supplements.
U.S. EPA, 1990. Designing and Implementing an Air Toxics Control
Program: A Program Development Manual for State and Local
Agencies. EPA-450/2-90-012.
U.S. EPA, 1991. Guidance on the Application of Refined
Dispersion Models for Air Toxics Releases. EPA-450/4-91-007
(NTIS No. PB 93-210359).
U.S. EPA, 1991. HEM-II Users Guide. EPA/450/3-91-0010.
Interested parties can obtain this document, and information on
how to access HEM-II, by contacting Warren Peters, at the EPA's
Office of Air Quality Planning and Standards. (919) 541-5337.
U.S. EPA, 1992. User's Guide for the Industrial Source Complex
(ISC2) Dispersion Models. Volumes 1, 2, and 3.
EPA-450/4-92-008a-c. (NTIS Nos. PB 92-232461, and PB 92-232453,
and PB 92-232479, respectively).
U.S. EPA, 1992. A Tiered Approach for Assessing the Risks Due to
Sources of Hazardous Air Pollutants. EPA-450/4-92-001.
(NTIS No. PB 92-164748).
U.S. EPA, 1992. User's Guide to TSCREEN; A Model for Screening
Toxic Air Pollutant Concentrations. EPA-450/4-90-013.
(NTIS No. PB 91-141820).
U.S. EPA, 1992. Workbook of Screening Techniques for Assessing
Impacts of Toxic Air Pollutants (Revised). EPA-450/R-92-024.
(NTIS PB 93-210367).
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U.S. EPA, 1993. Contingency Analysis Modeling for Superfund
Sites and Other Sources. EPA-454/R-93-001. (NTIS No. PB 93-
169126).
Risk Assessment Methodologies;
The following references include basic information on risk
assessment methodologies. See also appendix 2, particularly
IRIS, NATICH and Air RISC, for additional resources.
Calabrese, Edward, J., and Elaine M. Kenyon, 1991. Air Toxics
and Risk Assessment. Lewis Publishers, Inc., Chelsea, MI.
U.S. EPA, 1986. Risk Assessment Guidelines of 1986.
EPA-600/8-87/045.
U.S. EPA, 1990. Interim Methods for Development of Inhalation
Reference Concentrations. EPA/600-8-90-066A.
U.S. EPA, 1991. Guidelines for Developmental Toxicitv Risk
Assessment; Notice. 56 FR 63798. December 5, 1991.
U.S. EPA, 1992. Guidelines for Exposure Assessment; Notice.
57 FR 22888. May 29, 1992.
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APPENDIX 6 - HOW TO OBTAIN DOCUMENTS; HOW TO ACCESS DATABASES
HOW TO OBTAIN DOCUMENTS;
ATSDR DOCUMENTS
Department of Health and Human Services
U.S. Public Health Service
Agency for Toxic Substances and Disease Registry
Division of Toxicology
1800 Clifton Road, Northeast, Mail Stop E-29
Atlanta, Georgia 30333
(404) 639-6300
OHEA DOCUMENTS
Technical Information Staff
Office of Health and Environmental Assessment (8601)
U.S. EPA
401 M Street, Southwest
Washington D.C. 20460
(202) 260-7345
The OHEA Technical Information Staff distributes documents
published by the Office of Health and Environmental Assessment
Documents (includes many documents published by ECAO)
CERI
Center for Environmental Research Information (CERI)
Office of Research and Development
U.S. EPA
26 West Martin Luther King Drive
Cincinnati, Ohio 45268
(513) 569-7562
CERI disseminates documents published by the Office of Research
and Development (ORD)
NTIS
National Technical Information Service
5285 Port Royale Road
Springfield, Virginia 22161
(703)487-4650
(800)553-6847 (sales)
NTIS is the clearinghouse for all Federal documents.
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NIOSH - documents
National Institute of Occupational Safety and Health
Publications Dissemination
Division of Standards Development and Technology Transfer
4676 Columbia Parkway
Cincinnati, Ohio 45226
NTP - reports
National Toxicology Program
Central Data Management
Mail Drop-AO-01
National Institute of Environmental Health Sciences
Post Office Box 12233
Research Triangle Park, North Carolina 27709
ACGIH - documents
American Conference of Governmental Industrial Hygienists
6500 Glenway Avenue, Building D-5
Cincinnati, Ohio 45211
(513) 661-7881
HOTLINES/CLEARINGHOUSES
Air RISC
Air Risk Information Support Center
U.S. EPA
Office of Air Quality Planning and Standards (MD-13)
Research Triangle Park, North Carolina 27711
Hotline number (919) 541-0888
NATICH
National Air Toxics Information Clearinghouse
U.S. EPA
Office of Air Quality Planning and Standards (MD-13)
Research Triangle Park, North Carolina 27711
(919) 541-0850
to access NATICH on line:
Dial (919)541-5742. NATICH is available 24 hours a day except for
Mondays from 8:00 a.m. - 12:00 p.m.
Call (919) 541-0850 for assistance in accessing NATICH via
bulletin board.
COMPUTERIZED DATABASES/BULLETIN BOARDS
IRIS
Integrated Risk Information System
User Support (for General Information on how to access IRIS)
(513) 569-7254
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TOXNET
Toxicology Data Network
Specialized Information Services Division
National Library of Medicine
8600 Rockville Pike
Bethesda, Maryland 20894
(301) 496-6531
TIP
Toxicology Information Program
National Library of Medicine
Specialized Information Services
8600 Rockville Pike
Bethesda, Maryland 20894
(301) 496-1131
TIN
Technology Transfer Network
(919) 541-5742
for a 1200, 2400, or 9600 bps modem
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