ASTM E1848-20

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
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of the standard as published by ASTM is to be considered the official document.
Designation: E1848 − 96 (Reapproved 2014) E1848 − 20
Standard Guide for
Selecting and Using Ecological Endpoints for Contaminated
Sites
This standard is issued under the fixed designation E1848; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide covers an approach to identification, selection, and use of ecological endpoints (both assessment and measurement
endpoints) (1-8) that are susceptible to the direct and indirect effects of both chemical and non-chemical stressors or agents
associated with wastes and contaminated media at specific sites under current and future land uses. It does not address assessment
and measurement endpoints for non-site specific studies (for example, chemical-specific or regional risk assessments) or
measurements in abiotic media (soil, water, or air).
1.2 This guide addresses only the identification, selection, and use of assessment and measurement endpoints, not the full range
of activities that occur in an ecological assessment or ecological risk assessment at a contaminated site (1, 3-8). These activities
are addressed in other ASTM guides and references provided at the end of this guide.
1.3 This guide is intended to identify assessment and measurement endpoints to be used for screening, preliminary, focused,
detailed, and quantitative ecological risk assessments conducted in a linear or iterative fashion (3, 8). This is a partial, incomplete
listing of possible levels of assessment. In a tiered ecological risk assessment, it may be necessary to redefine ecological endpoints
when planning to collect more data or when additional site data are obtained and evaluated.
1.4 This guide is intended to be used by trained biologists, ecologists, and ecotoxicologists familiar with risk assessment, and
ecological and ecotoxicological concepts.
1.5 This guide (including Appendix X1) consists of a series of options or instructions and does not recommend a specific course
of action or provide detailed guidelines to be followed at all sites. See 2.2.2 of Regulations Governing ASTM Technical
Committees.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
This guide is under the jurisdiction of ASTM Committee E50 on Environmental Assessment, Risk Management and Corrective Action and is the direct responsibility
of Subcommittee E50.05 on Environmental Risk Management.
Current edition approved Jan. 1, 2014Nov. 1, 2020. Published March 2014January 2021. Originally approved in 1996. Last previous edition approved in 20082014 as
E1848 – 96(2008).(2014). DOI: 10.1520/E1848-96R14.10.1520/E1848-20.
The boldface numbers given in parentheses refer to a list of references at the end of the text.
Available from ASTM International Headquarters and the ASTM website, www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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2. Referenced Documents
4,5
2.1 ASTM Standards:
E943 Terminology Relating to Biological Effects and Environmental Fate
E1689 Guide for Developing Conceptual Site Models for Contaminated Sites
2.2 Other Documents:
EPA/100/F15/005 Generic Ecological Assessment Endpoints (GEAEs)For Ecological Risk Assessment: Second Edition With
Generic Ecosystem Services Endpoints Added, July 2016
Federal Contaminated Sites Action Plan (FCSAP) Ecological Risk Assessment Guidance, Government of Canada, March 2012
3. Terminology
3.1 Definitions—Definitions are provided specifically for use with this guide. Many of the terms listed in this section have been
modified from those defined in other publications (1-8).
3.2 Definitions of Terms Specific to This Standard:
3.2.1 assessment endpoint—an explicit expression of an environmental value (ecological, not monetary) to be protected (3).
3.2.1.1 Discussion—
An assessment endpoint is an ecological condition of potential concern or effect experienced by an ecological receptor with
ecological and societal value that drives risk-based decision-making at a contaminated site (for example, a specific reduction in
the abundance of a fish population or the disruption of the structure of benthic community). It is a qualitative, quantitative, or
quantifiable expression, measure, metric, or index involving an ecological receptor at risk. Under some circumstances, assessment
endpoints may be measured and used directly for assessment purposes. Assessment endpoints are the ultimate focus in risk
characterization and link measurement endpoints (see below) to policy goals and the risk management process (1-3, 5, 6, 8).
3.2.2 chemical stressor—a chemical, chemical mixture or radionuclide present in an environmental medium that is known or
suspected to induce an adverse biological, toxicological or ecological response in an exposed ecological receptor (3-8).
3.2.2.1 Discussion—
A chemical stressor is often referred to as an “ecological contaminant of concern.”
3.2.3 exposure area—a geographic location in which one or more site-related stressors are present and ecological receptors are
potentially exposed.
3.2.4 direct effect—an adverse impact on an exposed ecological receptor (for example, increased mortality or reduced growth) as
a result of the action of a site-related stressor.
3.2.5 ecological endpoint—a general term to refer to an assessment or measurement endpoint in an ecological risk assessment (2,
3).
3.2.5.1 Discussion—
Measurement of chemical concentrations in soil, water, or air are not ecological endpoints; these measurements indicate exposure
levels that may be used to evaluate the potential for an ecological response.
3.2.6 ecological receptor—ecosystems, habitats, communities, populations, and individual organisms (except humans) that can be
exposed directly or indirectly to site stressors (3, 4, 7, 8).
3.2.7 endpoint—an ecological characteristic (measure, metric, or index) that may be adversely affected by a site-related stressor
(4).
3.2.8 indirect effect—an adverse impact on an ecological receptor (for example, predator) resulting from the direct effect of a
stressor on another ecological receptor (for example, reduction in food supply or habitat).
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
A bibliography of related references and documents is provided in Appendix X2.
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3.2.9 indicator species—an organism that is typically common and represents a broad class of species present at the site or in
surrounding areas, or both.
3.2.9.1 Discussion—
There is sufficient information on its life history and response to contaminants to construct a model to predict (with uncertainty)
the potential for effects.
3.2.10 measurement endpoint—a measurable response to a stressor (measure, metric, or index) that is quantifiably related to the
valued characteristic chosen as the assessment endpoint (3).
3.2.10.1 Discussion—
Examples of a measurement endpoint are the reduction in the growth, survival, or reproduction of minnows in a standard laboratory
toxicity test. These examples of measurement endpoints would be appropriate for assessment endpoints defined as specific
predefined reductions in the growth, survival, or reduction in a forage fish population in a stream, river, or lake at the site (2-4,
8).
3.2.10.2 Discussion—
A measurement endpoint may serve as an assessment endpoint if the measurement endpoint (measured value) is the ecological
value to be protected. See related term measure of effect(9).
3.2.11 non-chemical stressor—a biological agent, physical disturbance, condition, or non-chemical characteristic of a waste
material, substrate, or source associated with a contaminated site and corrective actions that is known or suspected to interfere with
the normal functioning of an ecological receptor (3).
3.2.11.1 Discussion—
Non-native species, biologically engineered organisms, and pathogens are examples of non-chemical biological stressors.
Radiation other than that associated with specific radionuclides, erosion, dredging, impounding, grading, vegetation removal and
similar alterations/disruptions, altered particle size distribution, substrate instability, temperature and pH extremes, dissolved
oxygen content, water-holding capacity, organic content, physical effects of oil, and similar site characteristics unrelated to specific
chemicals are non-chemical stressors. No specific term is proposed for non-chemical stressors that corresponds to “ecological
contaminant of concern” for chemical stressors.
4. Significance and Use
4.1 This guide assumes that a decision has been made that an ecological risk assessment is required for a contaminated site. In
some cases, this decision could be made before any site data are collected. See Fig. 1.
4.2 The selection of assessment endpoints (defined as ecological values to be protected) and measurement endpoints (ecological
characteristics related to the assessment endpoints) is a critical step in conducting an ecological risk assessment. Endpoint selection
identifies those effects which are ecologically significant and not merely those that are adverse, thus providing a more rational and
defensible basis for making risk and remedial decisions.
4.3 This guide provides an approach for identifying, selecting and using assessment and measurement endpoints in an ecological
risk assessment for a contaminated site. This guide has been developed because there is no universal, simple measure of ecological
health analogous to measures used in human health risk assessment. Assessment and measurement endpoints have to be identified
and selected from a variety of individual circumstances on a stressor-, ecosystem- and scale-specific basis. It is important to
recognize that a diverse set of ecological endpoints could be required for a specific site. EPA/100/F15/005 Generic Ecological
Assessment Endpoints (GEAEs) For Ecological Risk Assessment: Second Edition With Generic Ecosystem Services Endpoints
Added. July 2016)
4.4 This guide is intended to be used primarily by a biologist, ecologist, ecotoxicologist, or a team of environmental scientists
during problem formulation and work plan development prior to initiating data collection activities at a contaminated site (3-8, 10).
4.5 Ecological risk assessment is usually an iterative process. In many circumstances it proceeds as a series of tiers, that is,
desktop/screening, preliminary, and detailed/focused phases. This guide can be used to refine or modify assessment and
measurement endpoints developed in earlier phases of the process.
4.6 This guide can be used whenever assessment and measurement endpoints must be identified and selected following an initial
or preliminary problem formulation/planning phase:
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FIG. 1 Conceptual Relationships between Assessment Endpoints, Measurement Endpoints and Lines of Evidence (Source: Federal
Contaminated Sites Action Plan (FCSAP) Ecological Risk Assessment Guidance, Government of Canada, March 2012)
4.6.1 Analysis phase (exposure assessment, hazard/effects assessment, stress/dose-response assessment;
4.6.2 Risk characterization phase; or
4.6.3 Remediation phase and possible subsequent ecological monitoring.
4.7 This guide is intended to be used in the evaluation of baseline conditions (current and future) and in the evaluation of
conditions resulting from remedial actions or corrective measures.
5. General Considerations
5.1 Ecological risk assessment is a process of evaluating risks to individuals (in the case of threatened or endangered species or
those afforded special protection), populations, communities and ecosystems exposed to chemical and non-chemical stressors.
Stressors can act individually or together over multiple ecosystem types and diverse spatial scales. Conditions of the site and risk
assessment that should be considered in identifying and selecting assessment and measurement endpoints include (2,3):
5.1.1 Stressor Characteristics—Types, properties, intensity, interactions, and spatial and temporal patterns;
5.1.2 Ecosystem Types—Aquatic, terrestrial, and wetlands and their subcategories (for example, marine);
5.1.3 Spatial Scale—The exposure area over which the exposure to the stressor occurs and direct and indirect ecological effects
are potentially produced;
5.1.4 Temporal Scale—The expected duration of exposure (acute to chronic) to the stressor, direct and indirect ecological effects,
and recovery time following removal of the stressor;
5.1.5 Ecological Organization—The level of biological organization (individual, population, community, or ecosystem) at which
risk to an ecological receptor is to be assessed; and
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5.1.6 Functionality/Values—Site-specific factors contributing to the importance of local ecological receptors.
5.2 Assessment and measurement endpoints are selected for specific ecosystem and stressor combinations associated with a site.
Assessment and measurement endpoints may address multiple ecosystem and habitat types, spatial and temporal scales, and levels
of ecological organization.
5.3 The conceptual site model describes sources, releases and transport pathways for contaminants present at a site. This
information is used to define exposure pathways and exposure areas and is usually developed before identifying and selecting
endpoints. Assessment and measurement endpoints should be identified for all exposure pathways considered at a site. Ecological
endpoints become part of the conceptual site model. Exposure pathway/exposure area and combinations of assessment and
measurement endpoints can be selected from this large set for subsequent analysis. Guide E1689 should be consulted on procedures
for developing the conceptual site model.
5.4 The following characterize some of the uses or roles of assessment and measurement endpoints in an ecological risk
assessment:
5.4.1 Incorporate resources potentially at risk or that require protection into the risk assessment process;
5.4.2 Complete development of a conceptual site model and problem formulation;
5.4.3 Design field and laboratory studies, toxicity tests, and other data collection requirements;
5.4.4 Focus site remediation/corrective actions;
5.4.5 Evaluate potential efficacy of remedial alternatives/technologies; and
5.4.6 Evaluate recovery of impacted populations, communities, and ecosystems.
6. Desirable Characteristics of Assessment and Measurement Endpoints
6.1 Desirable characteristics of assessment endpoints include, but are not limited to, the following (2,3):
6.1.1 Relevant to decision-making, local public concerns, and ecological considerations (societal or ecological relevance, or both);
6.1.2 Relevant to the site or surrounding area, or both, under current or future land uses, or both (current and future endpoints may
be different);
6.1.3 Potentially susceptible to adverse effects from exposure to one or more site contaminants or stressors;
6.1.4 Consistent with the spatial and temporal scale of the action of stressors present at the site;
6.1.5 Address ecological receptors that are expected to receive higher exposure to site contaminants or stressors relative to other
ecological receptors;
6.1.6 Amenable to hypothesis formulation, evaluation, and prediction; and
6.1.7 Value to be protected is clearly defined.
6.2 Desirable characteristics of measurement endpoints include, but are not limited to (2,3):
6.2.1 Correlated with or can be used to predict or infer changes in an assessment endpoint;
6.2.2 Relevant to the site and/or surrounding area under current or future land uses, or both;
6.2.3 Consistent with the spatial and temporal scale of the action of stressors present at the site;
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6.2.4 Capable of detecting an adverse effect of concern in the presence of one or more site stressors;
6.2.5 Amenable to hypothesis formulation, measurement and prediction;
6.2.6 Clearly defined; and
6.2.7 Known range of expected variability.
7. Candidate Site-Related Ecological Receptors
7.1 In general terms, ecological receptors that are subjects of assessment and measurement endpoints include, but are not limited
to, individuals and populations of a particular species, assemblages of species and communities, and habitats and ecosystems
potentially exposed at or in the area surrounding the site. All organisms within the exposure area are potential receptors.
Information should be available to indicate that organisms selected are potentially affected in an adverse way by site stressors (4).
This may require the use of data on related or surrogate species if data on indigenous species cannot be located (4).
7.1.1 Candidate species that can serve as ecological receptors at the individual organism and population level include, but are not
limited to:
7.1.1.1 Endangered, threatened, or rare species known or suspected to be present in the vicinity of the site;
7.1.1.2 Federal or state protected species;
7.1.1.3 Species in which populations have recreational, commercial, or other aesthetic or spiritual value to humans;
7.1.1.4 Species that contribute to the creation of important habitat for other species;
7.1.1.5 Species that show mutualistic behavior that enhances the reproduction or dispersal of other species;
7.1.1.6 Consumers (for example, parasites and predators) that are known or suspected to strongly regulate populations of other
species associated with the site and surrounding area to the extent that their absence would lead to a decrease in species diversity,
changes in community composition, or relative abundance of species; and
7.1.1.7 Other indicator species.
7.2 Candidate assemblages of organisms, communities, and habitats that can serve as ecological receptors include, but are not
limited to (3, 4, 8, 10,11):
7.2.1 Fish communities,
7.2.2 Benthic communities,
7.2.3 Avian communities,
7.2.4 Feeding guilds,
7.2.5 Wetland plant communities,
7.2.6 Terrestrial relict or protected communities and habitats,
7.2.7 Soil invertebrate and microbial communities, and
7.2.8 Other guilds, communities, and habitats of unique importance to the site.
7.3 If used, indicator species should be selected on the basis of potential effects, contaminant exposure, local abundance, habitat
requirements, and trophic position (for example, herbivore, piscivorous bird) in the community, habitat or ecosystem being studied
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(3, 4, 8, 11). Indicator species can be selected on the basis of site characteristic for all potentially complete exposure pathways,
exposure areas, and a variety of trophic positions, as appropriate.
7.4 Mobility, seasonal migration and extent of exposure to the site and exposure areas associated with site releases should be
considered, as appropriate, in selecting each receptor for the assessment.
8. Candidate Assessment Endpoints
8.1 Assessment endpoints may be stated qualitatively or quantitatively. Criteria for quantitative changes in specific candidate
assessment endpoints are established during problem formulation through a dialog between the risk assessor and the risk manager.
The list of possible ways to express assessment endpoints is potentially quite long (1-6,8, 9, 12, 13). The following subsections
provide examples of assessment endpoints and examples of how to state them (in quotes following each list). Documentation of
specific assessment endpoint statements is discussed in Section 12. Ecological significance relating to assessment endpoints is
discussed in Reference (14).
8.2 Candidate assessment endpoints at the ecosystem level of biological organization may include, but are not limited to:
8.2.1 Significant or a specific level of or percentage reduction in ecosystem productivity;
8.2.2 Significant or specific adverse changes in nutrient regeneration and cycling; and
8.2.3 Significant or specific adverse changes in energy flow.
8.2.4 An ecosystem-level assessment endpoint can be stated as “loss or diminishment of a specific ecological function (for
example, nitrogen cycling)” or “degradation or destruction of a specific habitat associated with a site or release.” The extent of loss
of function or degree of change is established during problem formulation for the specific site characteristics, receptor species, and,
if appropriate, reference site conditions.
8.3 Candidate assessment endpoints at the community level of biological organization include, but are not limited to:
8.3.1 A significant (or specific percentage) reduction in species diversity/richness;
8.3.2 Significant (or specific) adverse changes in the structure of a specific food web or plant community;
8.3.3 A significant (or specific) reduction in the market value of a specific sport or recreational fishery; and
8.3.4 A significant (or specific) reduction in aesthetic value of a habitat or community.
8.3.5 Community-level assessment endpoints can be stated as “a significant (or specific) reduction in the species richness of a
benthic community” or “a significant (or specific) reduction in the yield and quality of a stream fishery.” A specific reduction
criterion can be established during problem formulation.
8.4 Candidate assessment endpoints at the population level of biological organization include, but are not limited to:
8.4.1 A significant (or specific) reduction in population abundance;
8.4.2 A significant (or specific) lowering of reproductive success;
8.4.3 Changes in age, sex, and size structure that could lead to significant (or specific) reductions in population abundance; and
8.4.4 Local extinction in a defined area.
8.4.5 Population-level assessment endpoints can be stated as “absence of a species normally expected to occur in the vicinity of
the site” or “reduction of a population or subpopulation by pre-defined criteria attributable to contaminants associated with the
site.” Specific criteria for the changes listed above are developed during problem formulation.
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8.5 Candidate assessment endpoints for individual organisms include, but are not limited to, specific adverse changes in the
following:
8.5.1 Physiological status,
8.5.2 Reproduction,
8.5.3 Growth/biomass change,
8.5.4 Development,
8.5.5 Morbidity and mortality, and
8.5.6 Behavior.
8.5.7 An organism-level assessment endpoint can be stated as “adverse effects on an individual organism sufficient to cause a
decrease in survival, growth or reproduction.” Adverse effects include behavioral abnormalities, cancer, genetic mutation, physical
malformation and disease, and other adverse unspecified effects. Specific criteria for these assessment endpoints are established
during problem formulation.
9. Selecting Measurement Endpoints for Specific Assessment Endpoints
9.1 One or more measurement endpoints may be selected for each assessment endpoint (2, 3) if the assessment endpoint is not
amenable to direct measurement. Measurement endpoints usually involve data or results from a combination of laboratory and field
investigations (2-6, 8, 9, 12, 13, 15). These data and results are evaluated relative to the relationships between measurement and
assessment endpoints defined during problem formulation. Decision criteria for their evaluation are established on a site-specific
basis. Accordingly, the relationship between measurement and assessment endpoints must be clearly described as part of the
measurement endpoint selection process. Variability in parameters and characteristics must be addressed in defining measurement
endpoints and their relationships to assessment endpoints (1-3, 5-8). The following subsections present a partial listing of
representative measurement endpoints. Others could be appropriate at a specific site (2-6, 8, 10, 12, 13, 15).
9.1.1 Measurement Endpoints Representing Ecosystem Assessment Endpoints—Field measurements of biomass, productivity, and
nutrient dynamics are the preferred endpoints at this level of organization (2, 12, 16). Laboratory microcosm and mesocosm studies
using site media or species, or both, can also serve as measurement endpoints for the assessment endpoints at the ecosystem level.
9.2 Measurement Endpoints Representing Community Assessment Endpoints—Biomass, productivity/respiration, number of
species, measures of species evenness, dominance and diversity, guild structure, relative abundance, community quality indices,
and changes in community type are appropriate measurement endpoints (2). Laboratory microcosms using site media/species can
also serve as measurement endpoints for the assessment endpoints at the community level. Population studies may be used to
support community-level assessment endpoints.
9.3 Measurement Endpoints Representing Population Assessment Endpoints—Presence/absence of indicator species, abundance,
biomass, plant cover (not habitat), basal area, age/sex/size distributions, reproductive performance, yield, productivity, morbidity,
and mass mortality are acceptable measurement endpoints at this level of biological organization. Bioassays and toxicity tests using
site media also can serve as measurement endpoints for the assessment endpoints at the population level.
9.4 Measurement Endpoints Representing Individual Organism Assessment Endpoints:
9.4.1 Death, growth, fecundity, overt symptomology (disease, physical deformity), biomarkers, tissue concentrations, and
behavioral changes are acceptable measurement endpoints at this level of biological organization. With proper interpretation,
bioassay and toxicity test results using site media can also serve as measurement endpoints for the assessment endpoints at the
individual organism level.
9.4.2 Responses of individual organisms to stressors could be extrapolated to the population level to permit the estimation of stress
effects on natality, mortality, net reproductive potential, and other demographic characteristics.
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10. Specific Steps in Identifying, Selecting and Using Assessment and Measurement Endpoints
10.1 This section summarizes the activities associated with identifying and selecting endpoints for a contaminated site. Appendix
X1 contains instructions for a checklist to assist in identifying assessment and measurement endpoints appropriate for specific site
conditions. Appendix X2contains a bibliography of supporting ecological information. Uses of endpoints following problem
formulation are discussed briefly.
10.2 Planning/Problem Formulation Phase:
10.2.1 Obtain clear statements of policy or socie
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