RESEARCH NEEDS FOR
Toxic SUBSTANCES AND
PESTICIDES IN
THE GULF OF MEXICO:
Prepared lor the Gufl of Mexico Program by AMS. Inc
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Toxic Substances and Pesticides in the Gulf of Mexico _ Table of Contents
'
RESEARCH NEEDS FOR TOXIC SUBSTANCES AND PESTICIDES
IN THE GULF OF MEXICO
Executive Summary .................................. 3
Definitions And Background ............................ 11
Toxic Inorganics - Strategic Research Needs .................. 19
Toxic Organics - Strategic Research Needs ................... 39
Pesticides - Strategic Research Needs ....................... 52
Synthesis And Conclusions ............................. 78
Bibliography ...................................... 85
Appendix A
List Of Workshop Participants ...................... 87
Appendix B
Workgroups .................................. 89
Appendix C
Workshop Agenda .............................. 90
Appendix D
Additional Publications ........................... 92
September 1993 page 1
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Toxic Substances and Pesticides in the Gulf of Mexico Executive Summary
EXECUTIVE SUMMARY
Although the Gulf of Mexico has been historically viewed as one of the most healthy
and productive U.S. coastal environments, during recent decades there has been
growing concern over decreasing environmental quality due to a variety of stressors.
Human activities in the surrounding areas of the Gulf of Mexico, the Mississippi
River basin, and other tributaries have introduced toxic substances and pesticides into
coastal and offshore waters. Urban development, industrialization, farming,
habitation, and recreation have all contributed to toxic loadings to the Gulf of Mexico.
However, there are insufficient data to determine the role of toxic substances and
pesticides in environmental degradation in the Gulf.
Recognizing these issues, the Gulf of Mexico Program established a Toxic Substances
and Pesticides Committee to characterize the risks posed by toxic substances and
pesticides, and to devise ways to prevent or mitigate contamination. The Committee
includes representatives from industry, government, and academia.
The Toxic Substances and Pesticides Committee has developed an Action Agenda
which summarizes information about toxic substances and pesticide sources and
burdens in the Gulf of Mexico and identifies an initial set of activities needed to
reduce toxic substance and pesticide inputs to Gulf waters. However, serious
information gaps remain concerning contaminants and contaminant impacts. A
priority activity identified in the action agenda was to conduct a workshop to identify
research needed on the fate and effects of toxic substances and pesticides in the Gulf
of Mexico. This research is critical to directing limited resources to the problems and
areas of greatest concern.
This research needs workshop was convened on August 23-25 in Sarasota, Florida.
Experts from academia, industry, and government participated in the workshop.
Importantly, the group reached consensus on the most critical research needs for toxic
substances and pesticides in the Gulf of Mexico. Because of the wide representation
of this group, its recommendations constitute a research strategy for the entire Gulf
community for the next 3 to 5 years. Future research (and funding for research) in
the Gulf of Mexico should focus on and address those areas targeted in this Research
Strategy.
After an introductory plenary session, workshop participants organized, according to
their expertise, into three workgroups on toxic inorganics, toxic organics, and
September 1993 page 3
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Executive Summary Toxic Substances and Pesticides in the Gulf of Mexico
pesticides. General research needs identified by the toxic inorganics workgroup
included the establishment of baseline conditions, development of bioaccumulation and
hydrogeologic models, standardization of assessment methods, development of metal
speciation and bioavailability models, and development of quantitative techniques for
integration of effects and exposure data. Major recommendations from the toxic
organics group focused on the development of status indicators of healthy Gulf
ecosystems, development of predictive and diagnostic tests for assessing ecological
effects, assessment of available data on anthropogenic inputs, and development of a
site-specific quality criteria for target pollutants in estuarine ecosystems. The
pesticides workgroup concentrated on broad-based research needs related to the
development and validation of hydrodynamic and ecological models, the identification
of problem pesticides, the interpretation and application of tissue residue data, and the
understanding of repeated short-term exposure events in the Gulf. Overall,
recommendations from these three groups can be categorized into the following
themes: characterization of exposure, characterization of effects, fundamental
research, continuous chemical and biological monitoring, and risk reduction and
pollution prevention. These themes represent the building blocks of an ecological risk
assessment.
Table 1 provides an overview of the workgroup recommendations, which are grouped
according to contaminant type. Related research needs for other contaminant groups
are cross-referenced, and applicable themes are also noted on the recommendations
listed in the table. The following codes are utilized in the table:
Cross References: T = Toxic Organics
O = Toxic Inorganics
P = Pesticides
Themes: A = Characterization of Ecological Effects
B = Characterization of Exposure
C = Fundamental Research
D = Continuous Chemical and Biological Monitoring
E = Risk Reduction and Pollution Prevention
page 4 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico
Executive Summary
Table 1. Overview of Strategic Research Needs
Summary Table
Name of Strategic Research Need
Crass Reference
Theme
Tone Inorganic* (I)
1.
2.
3.
4.
5.
6.
7.
8.
9.
timttAm^i'rrmi'aiit of Mcdtod* wed in Gulf Wide A**e*sment*
Estsblishmenl of Background or Reference Condition*
Development of Quantitative Technique* for Integrating Exposure and Effect*
Data
Development of a Toxic* Budget for the Gulf
Development and Validation of Effect* Evaluation Techniques
Mechanistic Research on Soeciation **M| Biosvailabititv
•" •
Development of Trophic Levvl Biosf cumulation Model* for the Gulf of
Mexico Food Chain*
Development of Hydrogeologic Model* of Chemical and Biotic Transport
Dynamic* at Appropriate Scale* of Resolution
PI.P2.04
P8.07.O1
01
PI
02.03.P7.P11
P4
O4.P1.P11
04.P1.P4
B
A
C
B,E
D
A
C
B
B
Toxk Organic* (O)
1.
2.
3.
4.
5.
6.
7.
Criteria for Healthy Gulf Ecosystem*
Predictive Ecological Effects Tests Battery
Diagnostic Ecological Effect* Tests Battery
Assessment of Loading/ Ambient Data and Modeling Need*
Atmospheric Deposition of Toxk Substance* and Pesticide*
Development of Site-Specific Water Quality Criteria for Organic Toxicant* in
the Gulf
Development of Continuou* and/or Integrated Sampling and Analyst* System*
for Toxic Organic Compound* in the Gulf of Mexico
C.D
K.P7
M
II,I8,t9,Pl.P2,P4
P7
O.P8
C
A
A
B
B.C
E
D
Pesticide* (P)
1.
2.
.3.
4.
5.
6.
7.
8.
9.
10.
11.
AsacMlhe Ecological Significance of Repeated. Acute Input* of Pesticide* in
the Gulf of Mexico
Understanding the Transport and Bioavailability of Pestkidc* Used in the Gulf
of Mexico
Development and Implementation of Pesticide BMP* for the Gulf of Mexico
Identify Which Pesticides are Causing Ecological/Health Effect* end Where
the Impacts are Most Significant
Development of Standard Toxicologies! Teat Method* Uiing Representative
Endemic Species
Standardization of Analytical Method* and QA/QC
Understanding itf Titmtril Contaminant FffKtt on Marine Mammal* and Top
Carnivores in dw Gulf of Mexico
Development and Evaluation of Remediation Strategic* for Contaminated
Habitat*
Develpoment of an Ecosystem Water Quality Rick Baaed Approach for Riak
Aaaeuincnt Uring Archived Tissue Contaminsnt Data
I1.M.B.I9.04
11,04
H.19.04
16.02.06
C.07
16.18
B
B
A.C
B.C
E
A
A.D.C
A.B
A
E
B.E
September 1993
page 5
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Participating Organizations Toxic Substances and Pesticides in the Gulf of Mexico
ORGANIZATIONS PARTICIPATING IN WORKSHOP
These research priorities will be returned to the environmental research community to
help focus research activities. That community was represented by the following
organizations at the workshop:
ABC Labs
Brookhaven National Laboratory
Giba-Geigy, Inc.
Exxon Biomedical Sciences Inc.
Florida Department of Agriculture
Florida Department of Environmental Protection
Florida Institute of Technology
Gulf Coast Research Laboratory
Gulf of Mexico Program
International Papet Company
Louisiana State University
Mote Marine Laboratory
National Marine Fisheries Service
Occidental Chemical Corporation
Shell Development Company
Skidaway Institute
Texas Parks & Wildlife Department
U.S. Army Corps of Engineers
U.S. Environmental Protection Agency
U.S. Fish & Wildlife Service
U.S. Food and Drug Administration
Union Carbide
University of Mississippi
University of North Texas
page6 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Introduction
INTRODUCTION
Goal of the Workshop
The goal of the workshop was to identify and rank research needs on the loading,
fate, and effects of toxic substances and pesticides in water, sediment, air, and biota
of the Gulf of Mexico. The ultimate goal is to establish a toxic substances and
pesticides information base to be used for comparative ecological risk assessment in
the Gulf of Mexico.
Gulf of Mexico Program
The Gulf of Mexico Program was formed to pioneer a broad geographic focus in
order to address major environmental issues in the Gulf before the damage is
irreversible or too costly to correct. The Program is a cooperative partnership among
federal, state, and local government agencies and organizations, as well as with
people and groups who use the Gulf. Regions IV and VI of the United States
Environmental Protection Agency (USEPA), which share jurisdiction over the five
Gulf Coast States (Alabama, Florida, Louisiana, Mississippi, and Texas), initiated the
Program in August 1988. The goals of the Gulf of Mexico Program are to:
• protect, restore, and enhance the coastal and marine waters of the Gulf of Mexico
and its coastal natural habitats;
• sustain living resources;
• protect human health and the food supply; and
• ensure the recreational use of Gulf shores, beaches, and waters—in ways
consistent with the economic well being of the region.
Toxic Substances and Pesticides Committee
During the early stages of Program development, eight priority environmental
problems were identified and the following Committees were established to address
each of these problems: Marine Debris, Public Health, Habitat Degradation, Coastal
& Shoreline Erosion, Nutrient Enrichment, Toxic Substances & Pesticides,
Freshwater Inflow, and Living Aquatic Resources. There are important linkages
September 1993 page 7
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Introduction Toxic Substances and Pesticides in the Gulf of Mexico
among the various Committees, and the Gulf of Mexico Program works to coordinate
and integrate activities among them.
To respond to the threats posed by toxic contamination, the Toxic Substances and
Pesticides Committee was charged with characterizing toxic substance and pesticide
contamination and devising ways to prevent or mitigate this contamination and its
impacts. The Toxic Substances and Pesticides Committee has been meeting for more
than four years to review information and data collected by citizens and scientists,
identify problem areas, discuss actions that can resolve the problems, and evaluate
methods for achieving and monitoring results. Its long-term goal is to reduce and,
where possible, eliminate adverse ecological impacts from toxic substances and
pesticides in the Gulf of Mexico system. (Appendix D lists previous publications of
the Committee.)
This Committee has developed an Action Agenda that summarizes information known
about toxic substances and pesticide sources, burdens, and effects in the Gulf of
Mexico, and specifies the primary activities needed to reduce toxic substance and
pesticide loadings to Gulf waters. One of these primary activities in this Action
Agenda is to conduct a workshop to identify research needed to fully evaluate the rate
and effects of toxic substances and pesticides in the Gulf of Mexico. There are
significant gaps in the understanding of sources and amounts of toxic substances and
pesticides discharged into the Gulf and its tributaries and the fate and effects of these
toxicants. This information is critical to conducting an ecological risk assessment for
the Gulf, which will help target actions and resources on the most significant threats.
Research Needs Workshop
To meet the Action Agenda requirement, the Committee convened a workshop on
August 23-25, 1993 at the Mote Marine Laboratory in Sarasota, Florida to identify
strategic research needs and develop a planning document for use by the entire Gulf
research community. Approximately 40 experts from government, academia, and
industry participated in this effort (see Appendix A for a list of participants) .
The goals of the workshop were to identify and rank research needs on the fate and
effects of toxic substances and pesticides in water, sediment, air and biota of the Gulf
of Mexico and to provide a five-year Research Strategy for the Gulf community. The
identified research will stimulate establishment of a toxic substances and pesticides
information base to be used for comparative ecological risk assessment of the Gulf of
Mexico. Comparative risk assessment uses the paradigm of comparing the risks
associated with various activities relative to the resource and identifying the
page 8 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Introduction
probability that impacts will occur with specific activities and to what extent.
Comparative risks may include other Gulf of Mexico Priority problems such as
marine debris, nutrients, etc. Comparative risk assessment will allow agencies to
focus limited resources on the most serious environmental problems affecting the Gulf
of Mexico.
To achieve workshop goals, three objectives were identified:
• Bring federal, state and local agency program and resource managers together
with industry representatives and research scientists to review the current
information base relative to toxic substances and pesticides in the Gulf.
• Identify additional research activities needed to address information gaps regarding
toxic substances and pesticides in the Gulf.
• Recommend Priority research activities that will address identified needs.
A steering committee was formed to help facilitate the organization and operation of
the workshop. Prior to the workshop, the participants were provided with the reports
describing the Action Agenda for Toxic Substances and Pesticides and a summary of
what is known about the relative loadings and potential importance of specific
chemicals to the Gulf.
At the workshop, a plenary session was devoted to introducing the charge of the
workshop and summarizing existing information on chemical inputs and biological
resources at risk. An example risk assessment study was presented along with a
discussion of ecological risk assessment to focus the group on the approaches to be
taken in the break-out sessions for developing the research strategy. Participants then
organized, depending on their expertise, into working groups on toxic inorganic
chemicals, toxic organic chemicals, and pesticides for individual research issue
development. Through a consensus building process, the working groups then
discussed current gaps in research and information relating to their topic area and
recommended specific strategic research activities. The groups also ranked these
research activities according to three levels of priority, reflecting the inherent
sequential order necessary for completing them.
In addition to many topic-specific research needs, the groups also identified several
overall cross-cutting research needs for the Gulf of Mexico. Future research and
funding for research in the Gulf should focus on those areas targeted in this Research
Strategy. This Research Strategy will be revised and updated to ensure that it remains
consistent with the evolving needs of the Gulf of Mexico Program.
September 1993 paoe 9
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Introduction Toxic Substances and Pesticides in the Gulf of Mexico
This document provides a brief overview of the threats of toxic substances and
pesticides in the Gulf of Mexico, listing specific research needs under three types of
contaminants: toxic inorganics, toxic organics, and pesticides. Each research need is
described in depth along with a detailed justification of its importance and suggested
initiation activities. Although all research needs identified in the strategy are
considered high priority, the working groups ranked their recommendations into three
categories: Priority 1, Priority 2, and Priority 3. These rankings reflect the fact that
some activities need to be completed before others can be initiated (i.e., Priority 1
recommendations should be completed first).
The Synthesis and Conclusions section summarizes cross-cutting issues that broadly
describe the workshop recommendations and affect all types of toxic substances and
pesticides research in the Gulf of Mexico. It is not coincidental that these issues
represent fundamental building blocks for an ecological risk assessment for the Gulf
of Mexico.
Figure 1. Guff of Mexico Structured Partnership
page 10 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Definitions and Background
DEFINITIONS AND BACKGROUND
As defined by the Gulf of Mexico Program Toxic Substances and Pesticides
Committee and for the purposes of this workshop, the following definitions apply:
(See The Toxic Substances and Pesticides Action Agenda for the Gulf of Mexico,
1993)
Toxic substances (including pesticides) are materials—either synthesized by humans
or present in Gulf of Mexico waters—that are capable of producing an adverse effect
in a biological system or seriously injuring ecosystem structure or function. It should
be noted that human and other pathogens were excluded from consideration by the
Toxic Substances and Pesticides Committee because these issues are being addressed
by the Public Health Committee. Many research needs identified in this document
will, however, provide information that can be used to assess the human health effects
of pesticides and toxic substances in the Gulf.
A pesticide, broadly defined, is any agent used to kill or control undesired insects,
weeds, rodents, fungi, bacteria, or other organisms. Thus, the term "pesticides"
includes insecticides, herbicides, rodenticides, fungicides, nematicides, and
arachnicides, as well as disinfectants, fumigants, and plant growth regulators. For the
purposes of this document, the term "pesticide" refers to chemical agents only;
biological agents are not addressed as part of this Research Strategy.
Toxic substance and pesticide contamination can be a serious problem in coastal
environments. While concerns about discharges of toxic substances in the Gulf of
Mexico are growing because of the increased concentration of industrial activities,
data are insufficient to determine the role of toxic substances and pesticides in
environmental degradation in the Gulf.
Inputs of Toxic Substances and Pesticides
Sources and amount of toxic substances and pesticides discharged directly into the
Gulf of Mexico are available through a variety of national and regional data bases and
other sources. Information about direct and indirect discharges to the Gulf from
upland watersheds and airsheds is not as easily accessible. USEPA's Toxic Release
Inventory (TRI) is a computerized data base containing public information on the
annual releases and transfers of approximately 320 toxic chemicals reported by U.S.
September 1993 page 11
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Definitions and Background Toxic Substances and Pesticides in the Gulf of Mexico
manufacturing facilities to USEPA and the states. Since 1987, federal law has
required facilities to report the amount of both routine and accidental releases of the
320 listed chemicals to the air, water, and soil, and the amount contained in wastes
transferred off-site. Some 695 facilities report this data within the 68 counties that
border the Gulf. According to 1989 TRI data, all five Gulf Coast States are listed in
the top 20 states nationally for total chemical emissions to the environment. Four
Gulf States (Alabama, Mississippi, Louisiana and Texas) were among the top five
states with the largest surface water discharges of chemicals. Other less identifiable
sources of pollutants enter rivers, estuaries, and coastal areas from runoff and
atmospheric deposition. Many of these nonpoint sources contribute chemicals and
pesticides, as well as other material, to the receiving waters of the Gulf of Mexico.
Although pollutant input estimates are critical to understanding the overall risks of
toxic substances and pesticides, they cannot be used alone to target contaminated
areas.
Comparable data are not currently available to address the fate and effects of these
discharges on the aquatic environment. A toxicant entering the marine environment
may remain in the water column or move into the sediment, biota, or atmosphere.
Several predictive fate models exist, but need to be refined and validated to
incorporate parameters such as flushing rates. Models for predicting effects are not
as available. Nevertheless, it is clear that toxic contamination may cause a slow,
subtle poisoning of water, soil, and aquatic resources that is fairly invisible to beach
users, boaters, or casual observers of Gulf waters.
Consequences for Living Resources
The toxic effects of chemical contaminants to aquatic organisms are dependent on
several factors, such as the bioavailability and persistence of specific contaminants,
and the interference of contaminants with metabolic processes (Capuzzo and Moore,
1986). The responses of organisms to toxic chemicals can be exhibited at four levels
of biological organization: 1) biochemical and cellular; 2) organismal, including the
integration of physiological, biochemical and behavioral responses; 3) population,
including alterations in population dynamics; and 4) community, resulting in
alterations in community structure and dynamics (Capuzzo and Moore, 1986). One of
the least understood problems is the effect of sub-lethal concentrations of toxic
materials on ecosystem function.
Signs of increasing degradation and contamination from toxic substances and
pesticides in the Gulf of Mexico include the following examples:
page 12 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Definitions and Background
• In a USEPA study of three Gulf Coast estuaries, sampling stations near heavily
industrialized sites yielded larger numbers of diseased fish and oysters when
compared to more distant sampling stations (USEPA, 1990b).
• Biscayne Bay (Florida), Mississippi Sound, and Galveston Bay (Texas) have been
reported (Overstreet, 1986) to contain striped mullet with mesenchymal
neoplasms; sciaenid and other fishes with lymphocystis; fish with ulcers, red
sores, fin erosion, and granulomata; crustaceans with shell disease; and other
"pollution-associated" diseases.
• According to NOAA National Status and Trends Mussel Watch data, mercury is
generally enriched in Florida sites, where 12 of 25 of the sites sampled are well
above average. The oysters from Old Tampa Bay and Lavaca Bay are especially
high in mercury (USDOC, 1987).
• In some locations in Texas, where oysters are known to be contaminated with
mercury, harvesting has been limited because of the potential of a human health
threat.
• The brown pelican became locally extinct in the northern Gulf because the
presence of the pesticide DDT in large quantities inhibited the pelican's ability to
reproduce (USEPA, 1991b; USEPA, 1990a). Regulatory controls have supported
the recovery of this species in many areas; however, the brown pelican remains
endangered in Texas.
• Total DDT is the most abundant chlorinated pesticide found in Gulf oysters. The
regional distribution of total DDT shows that four of the five highest
concentrations are associated with major river outfalls including the Brazos,
Mississippi, Mobile, and Choctawatchee rivers. There are also relatively high
total DDT concentrations at St. Andrew's Bay and Panama City, although there
are no major rivers nearby. Polycyclic aromatic hydrocarbons (PAHs) are also
highest in these regions. DDTs associated with soils may be transported
downstream and collect in estuaries. This process provides a plausible explanation
of the higher total DDT associated with major river outfalls. There are somewhat
higher concentrations near areas of higher population density (i.e., Galveston Bay,
Mobile Bay, etc.) (Wade et al., 1991).
• PCBs have been detected in all oyster samples analyzed in NOAA's National
Status and Trends (NS & T) Program. The highest regional concentration is from
St. Andrew's Bay.
September 1993 page 13
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Definitions and Background
Toxic Substances and Pesticides in the Gulf of Mexico
Moderately elevated concentrations of sediment pesticides and PCBs appear along
the central Louisiana coast (possibly associated with Mississippi River discharge)
and at isolated stations in Matagorda Bay and Galveston Bay (Texas). High
concentrations of chlorinated hydrocarbons are observed along the Mississippi-
northern Florida coast and at sampling stations in Tampa Bay. The most abundant
chlorinated hydrocarbons in Gulf of Mexico oysters are PCBs, DDTs, chlordanes,
and dieldrin. Overall, the geographical trends in organochlorine contaminant load
in oysters follow those observed in sediments (Texas A & M Research
Foundation, 1989).
Risk Assessment (USEPA. Fnmiwot* tor Eeologlctl /to* Aut^m**. 1992.)
Quantifying the sources and understanding the fate and effects of contaminants are
essential for evaluating the risks posed to the Gulf of Mexico. These data on
contaminants and affected resources can be organized- and analyzed through the
process of ecological risk assessment.
Ecological risk assessment is defined as a process that evaluates the likelihood that
adverse ecological effects may occur or are occurring as a result of exposure to one
or more stressors. Ecological risk assessments evaluate ecological effects caused by
human activities and natural phenomena. The term "stressor" is used to describe any
chemical, physical, or biological factor that can induce adverse effects on individuals,
populations, communities, or ecosystems.
The framework is conceptually similar to the approach used for human health risk
assessment, but it is distinctive in its emphasis in three areas. First, ecological risk
assessment can consider effects beyond those on individuals of a single species and
may examine a community or ecosystem. Second, there is no single set of ecological
values to be protected that can be generally applied. Rather, these values are selected
from a number of possibilities based on both scientific and policy considerations.
page 14
September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Definitions and Background
Finally, there is an increasing awareness of the need for ecological risk assessments to
consider nonchemical as well as chemical stressors.
The risk assessment framework consists of three major phases: problem formulation,
analysis, and risk characterization. Problem formulation is a planning and scoping
process that establishes the goals, breadth, and focus of the risk assessment. Its end
product is a conceptual model that identifies the environmental values to be protected
(the assessment endpoints), the data needed, and the analyses to be used. It is where
the problem is laid out and a strategy is designed to obtain the types and amount of
exposure and effects data to perform risk assessment.
The analysis phase develops profiles of environmental exposure and the effects of the
stressor. The exposure profile characterizes the ecosystems in which the stressor may
occur as well as the biota that may be exposed. It also describes the magnitude and
spatial and temporal patterns of exposure. The ecological effects profile summarizes
data on the effects of the stressor and relates them to the assessment endpoints.
Risk characterization integrates the exposure and effects profiles. Risks can be
estimated using a variety of techniques including comparing individual exposure and
effects values, comparing the distributions of exposure and effects, or using.
simulation models. Risk can be expressed as a qualitative or quantitative estimate,
depending on available data. In this step, the assessor also:
• describes the risks in terms of the assessment endpoint;
• discusses the ecological significance of the effects;
• summarizes overall confidence in the assessment; and
• discusses the results with the risk manager.
In order to conduct a comparative ecological risk assessment for the Gulf, many
preliminary steps must be taken. (See Figure 2).
September 1993 page 15
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Definitions and Background Toxic Substances and Pesticides in the Gulf of Mexico
Figure 2. Risk Assessment Diagram
The results of a risk assessment hinge on many factors, including the estimated
uncertainty of the results; social perceptions of risk; the population at risk; values
such as commerce, recreation, endangered species and supporting habitat, and
regulatory requirements. Interpretations are called risk management. Risk
management translates the scientifically obtained results of risk assessment into a
social decision regarding appropriate actions to reduce the risk (Pastorok et ol., date
unknown). Risk management must also try to consider combinations or interactions
of chemicals—potential impact of more than one toxicant. Due to the inherent
uncertainty associated with risk assessment and management, the most logical and
productive area in which to focus limited resources is pollution prevention or source
reduction which incorporates process modification, closed loop recycling, and product
substitution.
page 16 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Definitions and Background
Figure 3 represents a framework for understanding the various components of a risk
assessment. The columns represent the three stages of risk assessment-problem
formulation, analysis, and risk management and cross-constituent analysis. The rows
describe different procedural steps and tools needed to assist in the risk assessment.
Currently, a comprehensive ecological risk assessment or characterization can not be
conducted for the Gulf of Mexico because there is a lack of information needed to
fully carry out many of these preliminary steps. The primary goal of the Research
Needs Workshop was to determine the most critical research needed to fill these gaps.
Ultimately, a comparative ecological risk assessment can be conducted focusing Gulf
of Mexico resources on high priority problems.
September 1993 page 17
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Definitions and Background Toxic Substances and Pesticides in the Gulf of Mexico
Figure 3. Risk Assessment Matrix
page 18 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico
Toxic Inorganics
TOXIC INORGANICS - STRATEGIC RESEARCH NEEDS
Overview
For the purposes of this workshop, the discussion of inorganic contaminants was
confined to metals only. Although the workshop participants acknowledge that other
inorganic constituents can represent potential pollutants in the Gulf of Mexico system
(e.g., salinity, nutrients, radionuclides), they made recommendations exclusively on
trace metals for two reasons. First, other GOMP committees are addressing nutrient
and salinity issues. Second, metals are perceived to be the greatest problem in the
Gulf by a wide audience.
General needs identified by the workgroup included the establishment of baseline
conditions, development of bioaccumulation and hydrogeologic models,
standardization of historical data, validation of current assessment and evaluation
techniques, and development of quantitative techniques for overall risk assessment.
Workgroup Participants:
BUI Adams (Chair)
Denny Buckler (Co)
Fred Colder
Kellie Dixon
Mike Lewis
Sonny Mayer
Simone Metz
Bill Walker
Herb Windom
Parley Winger
Steve Wolfe
ABC Labs
U.S. Fish and Wildlife Service
Florida Department of Environmental Protection
Mote Marine Laboratory
U.S. EPA
U.S. EPA—Gulf Breeze
Florida Institute of Technology
Gulf Coast Research Laboratory
Skidaway Institute
U.S. Fish & Wildlife Service
Florida Department of Environmental Protection
September 1993
page 19
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Toxic Inorganics
Toxic Substances and Pesticides in the Gulf of Mexico
Strategic Research Needs:
Priority 1. Critical Review of Existing Chemical, Biological and Physical
Level 1 Data
2. Standardization of Methods Used in Gulf Wide Assessments
3. Establishment of Background or Reference Conditions
4. Development of Quantitative Techniques for Integrating Exposure and
Effects Data
Priority 5. Development of a Toxics Budget for the Gulf
Level 2 6. Development and Validation of Effects Evaluation Techniques
7. Mechanistic Research on Speciation and Bioavailability
8. Development of Trophic Level Bioaccumulation Models for Gulf of
Mexico Food Chains
Priority 9. Development of Hydrogeologic Models of Chemical and Biotic
Level 3 Transport Dynamics at Appropriate Scales of Resolution
page 20
September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Inorganics
1. Critical Review of Existing Chemical, Biological and Physical
Data
Research/Information Needs:
There is a need for data suitable to assess Gulf of Mexico-wide and sub-regional
metal levels in sediments and organisms and to assess biological effects associated
with specific contaminant loadings in the Gulf and its coastal systems.
Rationale:
A data base with known comparability in measurements based on proper
documentation is essential to identifying contaminant levels with confidence and
securing informed public support for environmental restoration and pollution
prevention.
A variety of procedures have been employed to generate metal values. The following
problems are associated with the existing data base:
• Concentrations of metals are based on either partial digestion (acid leach) or total
digestion. Biological samples in many instances have not had the contents of the
digestive track eliminated prior to sample treatment and often lack documentation
of organism size and tissue type.
• Procedures do not attain sufficiently similar precision and accuracy in
measurements to allow comparison. In addition, contaminant measurements are
not always accompanied by proper QA/QC documentation to allow evaluation.
• Metal data are not accompanied by sufficient background information to allow for
assessing the extent and severity of contamination.
Initiation Activities:
To address this issue, "a science review working group should be established to
develop criteria for evaluating chemical and biological data on the Gulf of Mexico and
to provide guidance and assistance in the compilation and evaluation of existing data.
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Existing compilations could be used for this review. These include: EPA Region IV
Sediment Quality Inventory, Gulf of Mexico Sediment Quality Inventory and the
Biological Effects Data Base for Sediments (BEDS). Recommendations for further
work in the Gulf of Mexico should be made following the evaluation of the data base
Either gaps created as a result of the evaluation or existing gaps need to be addressed.
The recommendations should also cover the need for background metal data.
Priority Level: 1
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2. Standardization of Methods Used in Gulf Wide
Assessments
Research/Information Needs:
There needs to be an outline of criteria to generate scientifically valid data and an
accompanying QA/QC plan that will allow data comparison.
Rationale:
Historical metal concentration data for sediments and tissues from most regions
include results of analyses using a variety of sample digestion techniques and
analytical methodologies. Many of these techniques and methodologies do not
produce comparable or valid results. For example, metal concentrations based on the
analyses of sediments using partial digestion techniques do not compare with those
based on total digestion. In addition, partial digestion techniques fail to provide
aluminum data necessary for normalizing data and for distinguishing between metal
sources (i.e., natural versus anthropogenic). Furthermore, standard reference
materials (i.e., NIST or NRG standards) are only certified for total metal content,
thus only results for total analyses can be easily validated. The primary difficulties
associated with trace metal data for biological samples is data generated using non-
depurated (lack of elimination of digestive track contents) samples and lack of
consistency in organism size and stage of development. Therefore, to assure that
future data produced for the Gulf of Mexico are consistent and valid, there is a need
to adopt standardized methodologies and establish a regional analytical quality
assurance program.
Initiation Activities:
To address this issue, the Technical Steering Committee for the Gulf of Mexico
Program should establish an independent science review group to initiate the
following steps:
• Establish consensus on methodologies to assess biota and sediments.
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• Organize a QA program that incorporates all regional scientists that are working
within Gulf of Mexico program activities.
• Establish a quality assurance program that includes sponsoring workshops that
bring together scientists to discuss ways of improving comparability of results and
intercalibration exercises, coordinating with other groups working on QA
improvements, and establishing a permanent QA committee to periodically review
data quality and make recommendations for improvements.
Priority Level: 1
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3. Establishment of Background or Reference Conditions
Research/Information Needs:
There is a need to develop methods for the determination of natural vs. anthropogenic
stressors and for the establishment of baseline chemical and biological values.
Rationale:
For the protection and management of Gulf of Mexico resources, it is imperative to
not only be able to determine the level, extent, or impact of contaminants, but to also
be able to determine whether these levels exceed "normal" or background levels or
effects. At present this can not be done effectively. This is necessary in order to
provide a "yardstick" with which to make value judgments about the quality of the
environment and to characterize the significance of impacts or potential impacts.
A significant body of knowledge exists regarding the presence of metals in a variety
of biotic and abiotic compartments of the Gulf ecosystem. Similarly, a wide array of
test methods are available for measuring biological responses in the plant and animal
components of the Gulf. Information on normal values for environmental responses,
as well as the variability associated with those responses, will enhance our ability to
make decisions regarding the significance of environments" stressors.
Initiation Activities:
To address this issue, laboratory and field studies will need to be designed to establish
normal or baseline values for chemical residues and biological responses. An initial
component of the process will be the development of definitive criteria for
identification and selection of appropriate reference or control sites for wetland,
estuarine, and marine habitats. At these sites, samples of biotic and abiotic
compartments can be taken over a sufficient period of time from which to determine
both mean baseline values and estimates of the inherent and seasonal variability
associated with those parameters. With this information in hand, more meaningful
interpretation of existing data on contaminant presence and biological responses in
other areas of the Gulf can be made.
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Unimpacted areas from the various habitats of the Gulf of Mexico should be sampled
to establish baseline concentrations of contaminants, community/population
parameters, and lexicological effects. The initial activity would be discrete, relatively
short term projects. However, continued input would be expected from ongoing
monitoring and research activities. Because of the pivotal nature of this research
need, baseline information on the chemical, biological, and lexicological components
of the system should be collected as quickly as possible.
Priority Level: 1
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4. Development of Quantitative Techniques for Integrating
Exposure and Effects Data
Research/Information Needs:
There is a need for the development of quantitative techniques for integrating
exposure and effects data.
Rationale:
To achieve a system-wide approach to the Gulf of Mexico, comparative risk
assessments are necessary to characterize the relative importance of various stressors
and identify sites of concern and resources at risk. This will require development and
validation of estuarine assessment protocols, but even more importantly, it will
require the development of quantitative and probabilistic analysis techniques for
integrating exposure and effects data.
At present, ecological risk assessments involve generation of large amounts of data on
exposure and effects that are derived under strict QA/QC conditions. Rather than
analyzing all data in an integrated fashion, a simple quotient method requiring small
amounts of the data is used to develop an estimate of risk. The quotient method
involves dividing the no-effect concentration for the most sensitive species by the =
predicted environmental exposure concentration that aquatic organisms may
encounter. An estimate of risk or a safety factor may then be applied to the value.
The existing approach increases the uncertainty of the risk assessment. Techniques
are needed that will use all of the data to allow for modeling multi-scenarios of
stressor impact and analysis and integration of disparate data sets. These techniques
will provide probabilistic risk assessments with reduced uncertainty, widely applicable
analytical approaches for comparative risk assessments, and more flexible and
complete data management systems, including CIS applications.
Initiation Activities:
The first step required is to create a technical group to determine what analyses,
information, and management capabilities would be expected from such a
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system. This could be accomplished near-term through a workshop setting. The
existing data will be used to develop and validate the system.
Priority Level: 1
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5. Development of a Toxics Budget for the Gulf
Research/Information Needs:
There is a need to develop a refined toxics budget for the Gulf that recognizes
contributions from extreme events.
Rationale:
While first order estimates of toxics budgets for the Gulf or tributary loadings exist,
the data and loading estimates that have been produced with data of questionable
quality (or of limited utility) may be insufficient for identifying the contributions of
extreme events.
A unified source inventory is currently incomplete for all of the Gulf of Mexico
watersheds. The amounts and components of chemical spills and the relative mobility
of the species typically are not included. There is inadequate collated information to
estimate the relationships between sources-surface water discharges and atmospheric
deposition—and the eventual loadings to the Gulf.
It should be emphasized that atmospheric deposition of toxicants is poorly quantified
compared to other sources. The variation in deposition from nearshore to mid-Gulf is
unknown. The toxics budget should include information on the amounts of inorganics
contained in groundwater and produced waters (released with drilling muds on-site
during oil and gas drilling activities) which contain substantial quantities of metals and
other toxicants.
Central American and Caribbean loading of toxics to the Gulf is presently
inadequately quantified. The relatively poor levels of treatment for sewage and
industrial effluents, the use of U. S. prohibited pesticides, and the substantial mining
interests in the Central American region may represent a large fraction of metal
contributions to the Gulf.
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Initiation Activities:
An initial project to address this research need would include the following tasks: list
potential pathways, acquire any existing data pertinent to loading rates, identify the
quality of each data set, identify Gulf-specific information still lacking, and
incorporate best estimates from data in other regions as applicable. The proportion of
contributions during extreme events should also be addressed. This effort is viewed
as a short term effort, parameters of which may be revisited as additional information
becomes available. Depending on the utility of information from other regions, short
term projects may be identified to provide estimates for all pathways.
Priority Level: 2
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6. Development and Validation of Effects Evaluation
Techniques
Research/Information Needs:
There is a need for the development of ecological effects evaluation techniques to be
used Gulf-wide to ensure comparability of results. Although these standards should
not stifle creativity, there should be a minimum data set required for all evaluations.
Rationale:
The ecological health of the Gulf of Mexico and its associated estuaries is relatively
unknown, although there are indications that it may be declining. Assessment
techniques and protocols have been reported to analyze the flora and fauna in this
region, but they have not been evaluated for relevance and utility. These assessment
techniques are needed to more accurately determine the ecological condition of the
Gulf and to ensure that its economic and recreational importance is maintained.
Development of effects evaluation techniques and their validation contains two major
components: evaluation of specific endpoints as indicators and the validation of
assessment protocols. We need to maximize the efficiency of data gathering by
determining endpoints that are appropriate to specific ecosystems of interest. The
relative sensitivities and ecological relevance of various biomarkers, tissue burdens,
and community parameters currently are not clear. Many estuarine assessment
protocols developed for the Gulf are conceptual in nature, and much of the baseline
data are from laboratory studies. It is not clear if these assessment paradigms are
appropriate and effective for assessing effects in complex estuarine ecosystems,
especially the Gulf.
Initiation Activities:
We suggest that current broad-scale assessment programs conducted by NOAA,
USFWS, and USEPA in the Gulf of Mexico should be used as the focal point for
future protocol development and endpoint evaluation. Sampling and analytical
activities are being completed in multiple estuaries in the Gulf including Back Bay of
Biloxi, MS and Pensacola and Escambia Bays, FL. Techniques and approaches
utilized in these individual studies, and those conducted by NOAA and USFWS, could
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be immediately evaluated and assessed relative to results generated. The techniques
could also be consolidated into a consensus protocol to be validated in additional
Gulf-estuarine systems. A multiyear effort could begin immediately with a team of
8-10 research personnel. Sufficient analytical chemical support will also be needed
to timely process samples of sediment, water, and biota. By building on efforts
already underway, the probability of success in the relatively near term is high.
This effort will help establish baseline conditions for a healthy Gulf ecosystem
Assessment activities at suspected impacted sites will necessarily require simultaneous
assessment of reference areas, thereby providing information for the reference site
database.
Priority Level: 2
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Inorganics
7. Mechanistic Research on Speciation and Bioavailability
Research/Information Needs:
There is a need to understand toxicity changes as a result of the molecular speciation
of toxicants induced by surrounding physical-chemical conditions.
Rationale:
The toxicity of many ionic (and nonionic) toxicants may vary widely as a result of
other physical-chemical factors (e.g., pH, alkalinity, hardness, salinity, and sediment
grain-size, AVS content, and iron oxide/manganese oxide surfaces).
Some of this variability is caused by altered toxicant species and bioavailability. For
example, competition among available ions at effect sites (e.g., heavy metal ions
competing with "nutrient" metal ions at uptake channels in gill membranes) may
occur. Some variability is caused by changes in speciation of the molecules resulting
from altered equilibria because of the presence of other ions (e.g., silver's shift from
Ag+ to AgCl, AgC12, and AgCB as the surrounding salinity increases). Some
variability is also likely from presently unknown factors.
While the i peciation in water of many metals can be modeled using the EPA
MINTEQ or other similar programs, the toxicity changes from this speciation may be
enormous, and are generally poorly understood. Most toxicity testing, particularly of
metals, has been performed in the absence of understanding the molecular species to
which the organisms were exposed.
Initiation Activities:
• Where the speciation knowledge and the available water chemistry data during
bioassays are sufficient, toxicity test results should be analyzed in light of the
exposure to molecular species.
• These results should then be compiled to provide information on toxicity of
molecular species. -
• Any research funded out of the Gulf of Mexico program should be required to
consider these factors in experimental design.
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• Estimated time to complete the projects would be one year.
Priority Level: 2
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Inorganics
8. Development of Trophic Level Bioaccumulation Models for
Gulf of Mexico Food Chains
Research/Information Needs:
There is a need to better understand bioaccumulation of organic and inorganic
contaminants in the Gulf of Mexico food chains to perform ecological risk
assessments.
Rationale:
The concept of trophic level transfer of contaminants is based on the recognition that
contaminants can be taken up by aquatic organisms from water and/or sediments and
passed on to consumer organisms. The contaminant of interest may be maintained as
a body burden (residue) by organisms at several trophic levels and passed on to
successively higher trophic levels resulting in trophic transfer. Trophic transfer
involves contaminant uptake, metabolism, and depuration. The transfer of
contaminants from one trophic level to the next may or may not result in successively
higher concentrations of chemicals from one level to the next (biomagnification)
depending on the physical/chemical properties of the contaminant.
Trophic transfer is an important process that results in the transport and
transformation of metals within and outside of the Gulf system. Trophic transfer also
broadens exposure pathways. This process provides a direct means of exposure of
higher order organisms (including wildlife and humans) to contaminants contained in
the Gulf.
Ideally, quality data would be obtained on key metals for the Gulf (mercury,
cadmium, copper, zinc, and arsenic) for well-known food web systems. The data
would be modeled using food web models and would be extrapolated to food webs
other than those studied. Transfer coefficients would be developed and exposure
would be based on food consumption quantified for various components of the food
web. These data would then fit into an overall assessment of exposure for various
aquatic organisms in the Gulf.
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Toxic Inorganics Toxic Substances and Pesticides in the Gulf of Mexico
Initiation Activities:
• Review existing metals data on Gulf organism tissue levels. Select a specific site
(estuary) within the Gulf to focus research activities. Construct appropriate food
chain models for the selected site. Model the data and derive transfer coefficients,
derive exposure estimates for key species, evaluate other pertinent metals related
trophic transfer information and identify data gaps. This project is a short term
project and could be completed in one year.
• Fill data gaps and expand the data set to include trophic transfer models for
multiple estuaries and off-shore areas. This would be a long term project.
Priority Level: 2
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Inorganics
9. Development of Hydrogeologic Models for Sediment and of
Chemical Transport Dynamics at Appropriate Scales of
Resolution
Research/Information Needs:
There is a need for information that would allow modeling of toxicant fate as a result
of hydraulic flow, sediment movement, and biological transport mechanisms.
Rationale:
To perform a risk assessment, it is necessary to understand the movement of toxicants
into and through the Gulf of Mexico and its coastal waters and tributaries. This
requires an understanding of surface-water circulation patterns, ground-water flow to
the coasts, movements of sediments, and transport from the movement of and cycling
through the biota (e.g., migration, bloom uptake and deposition). Sediment transport
includes suspended sediments and bed-load from rivers, as well as resuspension (e.g.,
resulting from storms and dredging) and subsequent transport in coastal waters.
Some estuaries already have circulation models; however, many are two-dimensional
models that are relatively crude and insufficient for present needs. Open Gulf of
Mexico circulation has been studied on a large scale to the exclusion of small-scale
variations. This is because the physical oceanographers performing the studies are
not to determine environmental effects.
The ability to model the mass transport of toxics through these mechanisms will
contribute greatly to documenting and predicting effects, identifying areas of potential
problems, and in interpreting results of other studies. This understanding needs to be
on a scale pertinent to its intended use. The appropriate scale for a particular use
may include general Gulf of Mexico current patterns, longshore coastal transport, or
within-estuary circulation with greatest emphasis on near-shore movements.
Initiation Activities:
• Survey status of circulation modeling in Gulf of Mexico estuaries and any near
shore information.
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Toxic Inorganics Toxic Substances and Pesticides in the Gulf of Mexico
• Identify modeling methods that yield best results for toxicant-transport purposes.
• Prioritize locations where modeling is most needed to address current problems
and contract for their creation.
• Estimated time for completion would be one year for these projects.
Priority Level: 3
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Organics
TOXIC ORGANICS - STRATEGIC RESEARCH NEEDS
Overview
Protection and management of ecological resources in the northern Gulf of Mexico
require an understanding of the effects and impacts of anthropogenic activities
independent of natural ecosystem variations. Comprehensive systematic and
standardized methods to access anthropogenic impacts in general, and toxic impacts in
specific, have not been developed and/or widely applied in the Gulf. Major research
needs include:
• healthy Gulf ecosystem status indicators,
• predictive ecological effects tests, and
• diagnostic ecological effects tests for detection of the specific causes of measured
impacts.
In addition to these tests, assessment of available data on anthropogenic inputs,
including atmospheric deposition and ambient concentrations, are needed. Advanced
chemical analytical methods, including continuous and integrating sampling and
analysis methods and data treatment procedures, together with site-specific
estuarine/ecosystem sediment and water quality criteria for target pollutants, need
development.
Workgroup Participants:
Ed Overton (Chair) Louisiana State University
Linda Anderson-Camahan (Co) U.S. EPA, Region IV
Scott Can U.S. Fish & Wildlife Service
Nicholas Casseri Occidental Chemical Corporation
Dick Conway Union Carbide
Carol Daniels U.S. EPA - Environmental Research Laboratory
Thomas Deardoff International Paper Company
Robert Dickey U.S. Food & Drug Administration
Phil Dom Shell Development Corporation
Seymour Holtzman Brookhaven National Laboratory
Julia Lytle Gulf Coast Research Laboratory
September 1993 page 39
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
Ray Wilhour U.S. EPA - Gulf Breeze
Lloyd Wise Gulf of Mexico Program
Strategic Research Needs:
Priority 1. Criteria for Healthy Gulf Ecosystems
Level 1 2. Predictive Ecological Effects Tests Battery
3. Diagnostic Ecological Effects Tests Battery
Priority 4. Assessment of Loading/Ambient Data and Modeling Needs
Level 2 5. Atmospheric Deposition of Toxicants and Pesticides in the Gulf of
Mexico
6. Development of Site-Specific Water Quality Criteria for Organic
Toxicants
Priority 7. Development of Continuous and/or Integrative Sampling and
Level 3 Analysis Systems for Toxic Organic Compounds in the Gulf of Mexico
page 40 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Organics
1. Criteria for Healthy Gulf Ecosystems
Research/Information Needs:
There is a need for a suite of measurements and/or parameters that define the normal
stability and variability observed in healthy Gulf ecosystems. The measurements of
ecosystem health will be used to describe a normal system and identify healthy
systems representative of broad regions of the Gulf of Mexico. These parameters
should be:
• few in number and readily quantifiable,
• able to measure community and ecosystem health status,
• sensitive to stress, and
• able integrate change over time.
Rationale:
These "standardized" assessment tests are required to:
identify and describe a healthy estuary for monitoring/research reference;
classify estuaries as healthy, stressed, and degraded;
identify changes in health status over time to assess effectiveness of control
strategies (or the need to implement control strategies);
provide early warning signals of declining systems; and
compare Gulf-wide research and monitoring results;
The regionally representative "healthy ecosystems/estuaries" will be valuable as an
indexing function in coordinating assessment activities throughout the Gulf of Mexico.
A critical examination of EMAP, REMAP, and Walker's Biloxi Bay Study are needed
to standardize a suite of measures and/or criteria to describe a healthy ecosystem.
The applicability of these indicators Gulf-wide needs to be determined and modified,
where appropriate, to accommodate regional differences.
Initiation Activitiesr
• Regional workshop to evaluate current monitoring strategies and expansion needs.
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
• Utilize Biloxi workshop as a template.
• $ 1-2 million per year for each of 3-5 years.
Priority Level: 1
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Organics
2. Predictive Ecological Effects Tests Battery
Research/Information Needs:
There is a need for the identification, development, validation, and calibration of a
suite of tests (e.g., laboratory toxicity tests or in situ tests with animals and plants
utilizing sublethal end points, etc.) with sensitive life stages of indicator species to
identify and predict ecosystem problems in the Gulf of Mexico.
Rationale:
Contaminants entering an estuary from point or non-point sources may effect
organisms directly in the water column, be concentrated in the surface microlayer, or
be adsorbed to particulates. Sensitive stages of biota may be exposed to contaminates
via any of these compartments. Because the majority of persistent contaminants and
their degradation products entering estuaries eventually become associated with
sediments and are deposited in estuaries, it is critical that a suite of tests contain
sediment assays. Sediments may represent an integrated accumulation of contaminant
inputs to an ecosystem. However, it is not generally practical to predict which
sediment samples may be toxic on the basis of analytical chemistry information alone.
A suite of toxicity tests capable of detecting deleterious effects in water, surface
microlayer, and sediment samples are needed to assess potential contaminant
problems in the bays and estuaries of the Gulf of Mexico. These tests should be
compatible with diagnostic approaches (e.g., toxicity identification evaluations) for
evaluating the causes of any observed biological effects.
Initiation Activities:
Priority Level: 1
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
3. Diagnostic Ecological Effects Tests Battery
Research/Information Needs:
There is a need to identify and develop a battery of diagnostic tests to determine the
stressors causing the observed biological impacts in I and n (i.e., stressor
chaiacterization/evaluation/confirmation techniques).
Rationale:
In order to adequately assess the state of the Gulf of Mexico, there is a need to
supplement chemical specific analyses and single species toxicity test results with
population/ecosystem level health data. However, when population/ecosystem level
assessments indicate a problem with the health of an estuary, the sources) of the
impact may not be clear cut. Unlike the case of single species toxicity tests for which
toxicant identification evaluation methods have been and continue to be developed, no
such techniques exist to determine which of the many potential stressors present in an
estuary are causing the observed population/ecosystem effects. The battery of
diagnostic tests developed should have the ability to distinguish between effects caused
by toxic organic and inorganic chemicals, physical insults, biological stressors, etc.
This battery could include biomarkers, post-mortem examinations, marine sediment
toxicant identification evaluations, and single species tests coupled with chemical
assays. They should focus on the specific impact observed.
Initiation Activities:
A detailed workplan needs to be developed as an initial step. The concept of how a
battery of tests could diagnose the cause of several types of observed ecosystem
problems would first be examined in a paper study. This approach is analogous to the
tests used by medical practitioners to diagnose and establish causal relationships
between problems and stressors in humans. The paper study would be followed by
identification of an array of existing diagnostic ecological tests that may be useful
such as EPA's Toxicant Identification Evaluation procedures. Gaps in existing
techniques would be identified as methods development needs. The resulting
workplan should include a thoughtful rationale, identification of the most promising
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Organics
existing tests to evaluate first, test development needs, and a schedule for needed
laboratory and field work to apply/revise/validate the diagnostic test battery.
Priority Level: 1
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
4. Assessment of Loading/Ambient Data and Modeling Needs
Research/Information Needs:
There exists a need to re-assess available data, qualify its uses, and target
improvements and gaps. This also includes model development and use.
Rationale:
Gulf of Mexico-specific ecosystem-based toxics data are needed for predictive
assessment, problem identification and resolution, and resource allocation.
Mechanisms for flagging the data for various uses based on its quality and
development of assessment and data QA/QC protocols (not necessarily totally
standardized but equitable) need to be incorporated into existing databases. Selection
of critical input parameters for use in existing models and development of appropriate
Gulf-specific models that integrate toxic loading, ambient information, and exposure
and fate data are fundamental requirements for effective toxic management and
regulatory activities.
Initiation Activities:
An initial step in re-assessing existing data would be the screening of Gulf data from
various sources and identification of obvious data gaps.
Priority Level: 2
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Toxic Substances and Pesticides in the Gulf of Mexico Toxic Organics
5. Atmospheric Deposition of Toxic Substances and Pesticides
Research/Information Needs:
There is a need to develop information and methodologies which predict the
magnitude and effects of atmospheric deposition of toxic organic compounds into the
northern Gulf of Mexico.
Rationale:
The magnitude of TRI-reported toxic chemical emissions to air greatly exceeds the
magnitude of discharges directly to water, and recent studies have indicated that
atmospheric transport of toxic organic compounds from (primarily) point and fugitive
sources may be a significant mechanism of toxics input to water bodies, both via
direct deposition to water and deposition to land followed by runoff. Because of their
proximity to industrial and municipal point sources, Gulf of Mexico waters are
potentially at risk from airborne toxics input. This potential risk requires further
evaluation, including the effects of inputs to the' surface microlayer on pelagic
organisms.
Initiation Activities:
The mechanism of assessment will include:
• examination of existing atmospheric deposition data;
• examination of models used to predict atmospheric transport, fates, and
deposition to water bodies;
• selection of one or more models, including an assessment of the potential for
field validation of the model; and
• utilization of the model(s) to predict deposition of toxics to Gulf waters.
Air toxics release information from industry-provided TRI data, from recently
collected MACT studies data, and from state air toxics release submissions will be
utilized. The scale of the study will be determined after the model has been examined
and selected; it may be necessary to limit the first exercise to one or several specific
September 1993
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
Gulf water bodies, thus demonstrating the technique and providing an assessment of
the significance of this input to Gulf waters.
The activity is expected to require one to two years at a cost of $100,000 - 250,000 to
achieve the first deliverable (i.e.. the first report on atmospheric deposition to a
chosen water body). (A preliminary screening of the study to assess the magnitude of
the atmospheric deposition effect and the feasibility of more comprehensive effort
would cost from $50,000 to $100,000.) Assessment of the magnitude of the
atmospheric deposition effect and the feasibility of more comprehensive efforts would
cost from $50,000 to $100,000.
Priority Level: 2
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6. Development of Site-Specific Water Quality Criteria for
Organic Toxicants in the Gulf
Research/Information Needs:
There is a need to develop site-specific ambient water quality criteria for toxicants in
the Gulf of Mexico. Ambient water quality criteria for marine systems are only
available for a limited number of toxic pollutants. Little data are available for marine
species in the Gulf of Mexico, nor are there validations of protection offered by
national saltwater criteria in the Gulf of Mexico.
Rationale:
USEPA ambient water quality criteria are developed for nationwide applications.
Many of the existing criteria, however, apply only to freshwater environments. The
Gulf of Mexico's contiguous coastline is dominated by estuarine conditions with
varying salinities and organisms. Organic chemical toxicity is not only a function of
species sensitivity, but it is also a function of physical and chemical factors present in
receiving waters. The use of existing freshwater criteria for NPDES discharge
limitations can be inappropriate. There is a need to develop ambient water quality
criteria for the Gulf of Mexico for a different suite of resident/surrogate species that
are reflective of the diverse saline environments of the Gulf. Site-specific criteria
would be compared to a "toxicity test battery" and validated in an estuarine ecosystem
to determine comparative differences between the three levels of test complexity
according to EPA national guidance. This would result in the ability to predict
estuarine impacts from organic chemical pollution.
This work should focus on development of ambient criteria for those organic
chemicals identified as high Priority for the Gulf of Mexico because of release once
fate is considered, lack of a relevant data set using national guidelines, and perceived
lack of data on specific chemicals.
Test data development would proceed with selection of relevant species for
commercial interests, recreational interests, ecological interests, esthetic significance,
and range of occurrence. Specific effects of physical and chemical modification of
the control water would be included to evaluate the role of salinity, dissolved organic
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Toxic Organics Toxic Substances and Pesticides in the Gulf of Mexico
carbons, solids, pH, temperature, and pulse exposures that would result from a
significant storm event.
Initiation Activities:
This activity would cost approximately $200,000 per year for each of 5 years.
Priority Level: 2
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7. Development of Continuous and/or Integrated Sampling and
Analysis Systems for Toxic Organic Compounds in the Gulf
of Mexico
Research/Information Needs:
There is a need to develop continuous, integrated environmental sampling and analysis
systems for toxic organic compounds in the Gulf of Mexico.
Rationale:
The input and disposition of toxic organic compounds in the Gulf environment is non-
homogeneous. A multitude of methods for sampling and analysis exist for a wide
variety of known target compounds. These methods are largely time-consuming,
costly, and laboratory-based. There is a need for accumulative and real-time
sampling techniques, and cost effective, Meld deployable and analytically versatile
instrumentation for continuous environmental monitoring programs. Analytical data
from proposed instrumentation programs should be presented in a format useful to
environmental managers. Further, it is implicit and essential that methods and
instrumentation development comply with appropriate QA/QC controls.
Initiation Activities:
• Assess current technological capabilities in both commercial and federal sectors.
• Fund selective and promising research.
• Set up guidelines for commercial development incentives.
Priority Level: 3
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
PESTICIDES - STRATEGIC RESEARCH NEEDS
Overview
Ecological harm to the Gulf of Mexico and its resources can result from pesticide
usage and consequent runoff into the Gulf system. Successful comparative
assessments of the risks of various pesticides and pesticide usage practices hinge
largely on the existence of an adequate information base.
To address current information gaps, the pesticides workgroup identified a variety of
strategic research needs for the next five years. These needs fall into the following
major categories:
Modeling
Chemistry
Management Practices
Loading/Fate/Inputs
Toxicity (e.g., Ecological, Human, Methods) •
Impacts/Field Effects
Some broad needs identified included the development and validation of models, the
identification of problem pesticides, the interpretation and application of tissue residue
data, and the understanding of repeated short-term events in the Gulf. Essentially,
research in these areas would help fill information voids related to pesticide inputs,
management, and outputs. In turn, this new information would help the Gulf
community identify and select management options designed to reduce risks to this
vital ecosystem. Figure 4 provides an overview of this concept.
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Toxic Substances and Pesticides in the Gulf of Mexico Pesticides
Figure 4: PESTICIDE Flow Diagram
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Toxic Substances and Pesticides in the Gulf of Mexico
Workgroup Participants:
Jim Clark (Chair)
Bill Benson (Co)
Tom Bailey
Greg Cramer
Gary Dickson
Tom Dillon
Roxanne Dow
Catherine Fox
Mike Jahncke
"Smiley" Nava
Rich Pierce
Geoff Scott
Darryl Smith
Exxon Biomedical Sciences, Inc.
University of Mississippi
U.S. EPA
U.S. FDA
Ciba-Geigy, Inc.
U.S. Army Corps of Engineers
Florida Department of Environmental Protection
U.S. EPA - Office of Water
DOC/NOAA/NMFS
Texas Parks and Wildlife Department
Mote Marine Laboratory
NMFS, Charleston
Florida Department of Agriculture
Strategic Research Needs:
Priority 1. Develop and Validate Estuarine Ecosystem Models
Level 1 2. Update and Verify Contaminants Database for Tissue Residues,
Sediments and Water
3. Assess the Ecological Significance of Repeated, Acute Inputs of
Pesticides in the Gulf of Mexico
4. Understanding the Transport and Bioavailability of Pesticides Used in
the Gulf of Mexico
5. Development and Implementation of Pesticide BMPs for the Gulf of
Mexico
Priority 6. Identify Which Pesticides are Causing Ecological/Health Effects
Level 2 and Where the Impacts are Most Significant
7. Development of Standard Toxicological Test Methods Using
Representative Endemic Species
8. Standardization of Analytical Methods and QA/QC Criteria
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Toxic Substances and Pesticides in the Gulf of Mexico Pesticides
Priority 9. Understanding of Chemical Contaminant Effects on Marine
Level 3 Mammals and Top Carnivores in the Gulf of Mexico
10. Development and Evaluation of Remediation Strategies for
Contaminated Habitats
11. Development of an Ecosystem Water Quality Risk Based Approach for
Risk Assessment Using Archived Tissue Contaminant Data
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1. Develop and Validate Estuarine Ecosystem Models
Research/Information Needs:
An empirical understanding of the hydrologic dynamics apparent in estuarine systems
as they relate to the fate and dissipation of pesticides has not at present been achieved.
Therefore, the development and validation of an eco-model for estuarine ecosystems
is an important research need. Albeit trophic interactions and top predator integration
of primary energy sources have been studied to some degree, efforts to
mathematically incorporate these data into practical computer models of exposure and
effect have not been completed. Estuarine eco-models would be helpful in estimating
impacts to non-target organisms by:
• estimating degradation times (t1/2) in various components of the ecosystem
(i.e., intertidal zones, sediments, pore waters, interstitial sediments, etc.),
• determining the dissipation and fate of pesticides,
• estimating the effects of dilution and exchange on the bioavailability of
pesticides,
* providing more realistic exposure concentrations for estimating lexicological
effects, and
• linking acute and chronic effects on single species to population, community
and ecosystem effects.
Rationale:
One feature unique to the Gulf of Mexico is the tremendous influx of freshwater via
the Mississippi River. This feature would require special considerations for estuarine
ecosystem modeling due to the inconsistent hydrologic dynamics of the Mississippi
river drainage. Models for this ecosystem must specifically consider factors such as
marked nutrient loads, high sediment loads, diverse and often low salinity ranges, and
semi-diurnal tides. Additionally, pest control relating to fire ants, golf courses,
coastal residential developments, aquatic weeds, mosquito control, and marine fouling
create unique impact issues for the Gulf region.
A key component of assessing the potential impacts of pesticides on non-target
organisms is the ability to estimate the risk of chemicals to biota and to quantify
ecosystem effects. Risk is a factor of hazard, or general toxicity of a pesticide, and
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exposure, which is a determination of how, where, and in what quantity non-target
organisms are exposed to pesticides. While numerous models are available to
estimate pesticide input and fate for freshwater ecosystems, comparable computer
models have not been developed for estuarine systems.
The lack of a suitable computer model of estuarine dynamics has been a serious
limitation of regulatory risk assessments. Modeling information is critical for
adequately protecting susceptible estuarine species, which is based on better predictive
capabilities for pesticide input, dissipation, and bioavailability. Utilization of this
information will, in turn, lead to sound management practices. A significant effort to
validate and calibrate new models will be needed to establish confidence in the
predicted outcomes, by correlating field toxicity data with laboratory generated data.
Initiation Activities:
The resources needed to accomplish this goal would include, but not be limited to:
• Experienced mathematical modeling experts.
• Access to National/International databases via Local Area Networks (LAN) or
similar information transfer systems.
••* A team of experienced estuarine ecologists to include a marine hydrologist,
planktologist, invertebrate biologist, phycologist, microbiologist, fishery
biologist, ecologist, marine mammologist, and environmental toxicologists.
• Availability of research vessels equipped with on-board facilities for chemical,
biological, and hydrological analyses.
Priority Level: 1
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2. Update and Verify Contaminants Database for Tissue
Residues, Sediments and Water
Research/Information Needs:
There is a paucity of reliable, quality environmental monitoring data available Gulf-
wide or for many estuaries, bays, and sub-systems. Therefore, there is a need to up-
date as well as verify currently available pesticide contaminant databases for tissues, •
sediments, and waters of the Gulf of Mexico.
Rationale:
Historically, data available in contaminant databases often lacks appropriate
documentation of quality assurance and quality control. Furthermore, the data often
are flawed by poorly designed and inadequate sampling programs or are biased based
on the original sampling program needs. In view of these considerations, there is a
need to update as well as verify currently available pesticide contaminant databases
for tissues, sediments, and waters of the Gulf of Mexico. A comprehensive pesticide
contaminant database for the Gulf of Mexico will assist in comparison of clean,
minimally impacted (or controlled) areas with "contaminated" sites with similar
attributes and/or natural resources. Such a database will be useful in sound
management decisions regarding prioritization ol impacted areas, mitigation and/or
remediation strategies. The widespread availability of such a database is critically
important to ensure parody and consistency among the management agencies
bordering the Gulf of Mexico.
Initiation Activities:
Acquire and update as well as verify existing pesticide contaminant databases. Data
without appropriate quality control quality assurance documentation should be utilized
with caution in comparison to data acquired from a fully supported environmental
monitoring program.
Priority Level: 1
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3. Assess the Ecological Significance of Repeated, Acute
Inputs of Pesticides in the Gulf of Mexico
Research/Information Needs:
The ecotoxicological significance of pulsed inputs of pesticides into estuarine
ecosystems of the Gulf of Mexico is unknown, although this is the most likely
exposure regime following pesticide runoff events. While existing data may provide
estimates of individual, singe pulse events, the cumulative impact of repeated
pesticide inputs from multiple pesticide uses is unknown.
Rationale:
Non point source runoff or spray drift during application of pesticides near estuarine
ecosystems may result in repeated, acute, or chronic exposures of endemic aquatic
organisms to multiple chemicals. The standard laboratory tests used for estimating
chemical toxicity typically use continuous exposures over extended time periods (1 to
10 days) to characterize chemical hazards. This provides a great deal of uncertainty
in predicting or evaluating field effects from laboratory data. Documentation of the
toxicity resulting from single pulsed exposures at field sites are rare, while data on
repeated pulses and exposure-effect data are lacking. Present hazard and risk
assessments are inadequate to address the realistic, repeated, pulsed pesticide
exposures, particularly where repeated exposure may result in an increased sensitivity
to pesticides. Additionally, aquatic organisms are exposed to multiple pesticides
(herbicides, insecticides, fungicides) as well as dynamic physicochemical conditions
(salinity, dissolved oxygen, turbidity). For example, low salinity can enhance the
toxicity of pesticides and other contaminants. Alternatively, participates found in
runoff may serve as binding sites, and reduce the bioavailability of some pesticides.
Studies are needed to address issues such as:
• identification of effects of repeated, pulse exposures to pesticides on key indicator
organisms (fish, shellfish, crustaceans);
• evaluation of the effects of exposures to multiple pesticides;
• quantification of the interaction of water quality factors such as dissolved oxygen,
salinity, turbidity, and the toxicity or bioavailability of pesticides;
• linkages of site specific studies of pesticide impacts with regional resource
evaluations; and
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• ecological assessments to derive ecotoxicological hazard/risk assessment models
with spatial characterization of regional impacts from pesticides in Gulf of Mexico
habitats.
Ecotoxicological effects of realistic exposure regimes could then be linked to regional
models of pesticide loading and watershed transport to coastal habitats, providing
predictive management and assessment tools for assessment and mitigation of potential
pesticide impacts. Contaminant assessments of sediments and biota and surveys of
populations and communities in coastal habitats may be used to validate and
characterize the cumulative impacts of pesticides. A tiered approach should be used
which would begin by characterizing the land-estuarine interface followed by
subsequent characterization of estuarine nearshore and offshore interfaces.
A program directed at such an effort would provide accurate assessments of the
toxicity of pesticides under realistic field exposure regimes. In addition, the degree to
which chemical by chemical assessments accurately predict impacts of multiple
chemical exposures could be evaluated. Uncertainty in existing risk assessment
approaches could be addressed by establishing relationships between dynamic water
quality parameters and pulse, multi-chemical exposures.
Initiation Activities:
Remote, continuous, real-time monitoring and sampling equipment for water during
pulse exposure events. Appropriate support staff and facilities, including field crews,
analytical chemistry and toxicological testing.
Priority Level: 1
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4. Understanding the Transport and Bioavailability of Pesticides
Used in the Gulf of Mexico
Research/Information Needs:
Pesticides may teach coastal waters of the Gulf of Mexico as a result of surface
runoff, atmospheric deposition, groundwater seepage, and direct application. The
extent to which pesticides are transport: ' to coastal waters, their chemical form, and
their degree of bioavailability need to be evaluated.
Rationale:
An assessment of pesticide use in coastal areas of the U. S. by NOAA has concluded
that the amounts and types of pesticides used in the Gulf of Mexico, place the Gulf at
highest risk from pesticides among all coastal U. S. waters. The close proximity of
large agricultural areas to rich aquatic resources combined with a year-round growing
season and high rainfall result in a high potential for adverse ecological impacts of
pesticides on the Gulf of Mexico. There are also many other uses of pesticides in the
Gulf region that are not fully quantified, such as mosquito control, aquatic weed
control, marine-anti fouling compounds and termite and fire ant control. Research is
needed to document the amount and chemical form of these compounds entering the
Gulf system.
Loadings to coastal waters are influenced by diverse hydrologic dynamics, climate,
soil types, and various physico-chemical parameters. In addition, the persistence and
environmental partitioning characteristics of individual pesticides vary widely.
Consequently, site-specific use and field data need to be developed to determine actual
loadings to the Gulf of Mexico.
These data would improve current ecosystem models used to predict environmental
loading and risk assessment, lead to improved environmental management, and help
focus limited resources on pesticides most likely to result in ecological impact.
Further, they would provide pertinent information to address a variety of public health
concerns.
Modem society has become very dependent upon a wide variety of pesticides in
agriculture, consumer products and non-agricultural uses (e.g.. mosquito abatement,
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
weed control, etc.). While these compounds are commonly used, there is concern
that they cause many environmental "insults" with little actual knowledge of the
effects mechanisms. Not all pesticides are equally toxic or persistent, nor does mere
use automatically mean there is a negative effect on aquatic resources. For example,
although the National Academy of Sciences has concluded that pesticide contaminated
seafood presents a low human health risk except in certain site-specific areas, the
public, nevertheless, is fearful that seafood is contaminated. Because the Gulf of
Mexico supplies so much of the nations seafood, this concern must be addressed.
Initiation Activities:
Priority Level: 1
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5. Development and Implementation of Pesticide BMPs for the
Gulf of Mexico
Research/Information Needs:
There is a need for the development and implementation of pesticide management
approaches to reduce inputs into the Gulf of Mexico~a pollution prevention approach.
Rationale:
Pesticides have been known to cause a number of environmental problems in the Gulf
of Mexico. These include fill kills and shell fish contamination. In addition, other
unidentified impacts may be associated with pesticides because of their modes of
action and widespread distribution.
Data indicate a relatively large potential for pesticide inputs for the Gulf of Mexico
from a variety of sources. These include point and non-point sources, such as
agricultural and residential uses, mosquito control, marine anti-fouling, fire ant
control, golf course uses, waste water treatment facilities, and transport from distant
locations (aerial deposition, Mississippi River inflow). The relatively long growing
season and mild climate of the Gulf Coast also increases the use of pesticides
throughout the year. Some of these uses may introduce pesticides into the Gulf of
Mexico with relatively long residual times.
Although mitigation programs are being developed or are currently in use for specific
pesticide applications, many uses have no such programs. Some programs being used
are:
herbicide best management practices (BMP)
state water management programs
reduced application rates
new application techniques
integrated pest management programs (IPM)
impoundment or boundary areas
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Consideration of these techniques and the unique characteristics of the Gulf Coast use
patterns and loadings can be used to develop additional innovative ways to reduce
pesticide transport into the Gulf of Mexico.
Initiation Activities:
The development of a comprehensive database on pesticide loading into the Gulf of
Mexico would be necessary. Development of this information would require contacts
and coordination with a number of federal and state agencies, pesticide manufacturers
, and user groups. In order to further prioritize management efforts, the data of Pait
(Pait et al, 1992 and Pait, Farrow, Lowe, and Pacheco, 1989) which ranked
pesticides used in the Gulf of Mexico region according to characteristics which can
influence their environmental impact should be used. Characteristics included acute
and chronic toxicity, bioaccumulation potential, and persistence. This ranking,
coupled with the current loading information, would provide the Priority targets for
initiation of management programs.
An evaluation of current pesticide management techniques would provide those
methods with the greatest opportunity to reduce transport into the Gulf of Mexico.
New techniques also could be developed to address those uses and sources unique to
the Gulf Coast. Recommendations would then be provided to appropriate regulatory
and user groups for implementation. The effectiveness of these management
techniques could be monitored in future pesticide loadings into the Gulf of Mexico.
Priority Level: 1
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6. Identify Which Pesticides are Causing Ecological/Health
Effects and Where the Impacts are Most Significant
Research/Information Needs:
There is a need to identify not only which pesticides are causing ecological (and/or
human health) impacts in Gulf of Mexico estuaries, but also where the most
significant impacts are occurring.
Rationale:
Due to the large amount of agricultural land use, climate, and relatively long growing
season, large amounts of pesticides have been applied in areas which drain into the
Gulf estuaries. In addition, chemical characterization of estuarine sediments by
federal, state, academic, and other agencies have indicated the presence of high
concentrations of persistent pesticides (chlordane, dieldrin, endrin) in certain
estuaries, i.e., Laguna Madre, TX, and Calcacieu Take, LA. Additional studies in
these and other Gulf estuaries have demonstrated significant biological impacts as well
as elevated residues of pesticides in tissues and sediments. Many sediment quality
and biological assessment methodologies have recently been developed which have
had only limited success in linking historically contaminated sediments and tissue
residues with ecologically relevant effects. There is a need to review, evaluate, and
incorporate various approaches for data interpretation-particularly sediment and tissue
residue information-in order to establish cause and effect relationships.
The overall goal of this effort is to identify specific pesticides responsible for
detrimental ecological and human health effects. Potentially impacted areas can be
prioritized by ranking the degree and extent of pesticide contamination reported
through a detailed evaluation of sediment chemistry and biological effects data (both
new and historical). This important effort is needed to identify areas of concern and
implement effective management strategies which reduce and/or eliminate sources and
their resulting impacts on the ecological systems of the Gulf of Mexico.
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
Initiation Activities: .
Acquisition and review of existing information will be necessary to identify potential
areas and pesticides of concern, as well as for the identification of data gaps. To
avoid duplication of effort, to maximize use of the information collected, and to
minimize potential differences in data interpretation, federal and state agencies,
industry, environmental groups, academia, and the public will be involved.
Priority Level: 2
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7. Development, of Standard Toxicological Test Methods Using
Representative Endemic Species
Research/Information Needs:
Establishing cause and effect relationships for pesticides requires the ability to detect
detrimental biological impacts. This is accomplished through the use of standard test
methodologies with ecologically relevant endpoints that are responsive to acute and
chronic pesticide exposure.
Rationale:
Many standardized biological test methods are available which utilize various species
and examine numerous biological endpoints (i.e., growth, reproduction, physiological
indices). For example, mysids and menidia are widely used in acute and chronic
toxicity tests. The question becomes whether such tests are representative of the
more susceptible, site-specific endemic species and whether the biological endpoints
examined are indicative of ecologically relevant effects.
To address this problem, there is a need to develop short-term (10 day or less)
toxicity tests for susceptible life stages of representative endemic species that can be
used in combination with standard test organisms or bioindicator tests. The standard
test organisms provide a normalizing assessment for Gulf-wide comparisons, where as
community-specific test organisms provide site-specific information.
Biological indices (e.g., growth, reproduction, biochemical, physiological indices) to
be examined should provide a linkage with relevant ecological endpoints and be
protective of ecosystem health. Specific attention should be given to in situ
methodologies to address issues related to multivariable environmental exposure
conditions. Highest Priority research needs for biological methods development are in
the category of short-term tests to detect sublethal effects, resulting from both acute
or chronic exposures, with specific attention given to pulsed exposures to pesticides.
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
Initiation Activities:
Research needs include methodologies for appropriate use of biological effects
endpoints, approaches for evaluating the representativeness of selected species in site
specific hazard assessments, and approaches for quantifying exposure-response
relationships for ecological risk assessment. Validated methods such as these,
specifically designed for the unique Gulf of Mexico coastal ecosystems, will allow
prediction and assessment of current and future pesticide impacts.
Priority Level: 2
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8. Standardization of Analytical Methods and QA/QC Criteria
Research/Information Needs:
Because quantitative environmental chemistry is an ever-changing science, methods
used to analyze environmental samples for pesticide residues are continually changing.
New methods may overcome inaccuracies or interferences in older analytical methods,
making previous data suspect or unreliable. In order to retain and utilize as much
historic data as possible, methods comparisons and minimum data quality standards
must be developed. There is a research need for the following activities:
• Develop uniform criteria for pesticide analyses in different matrices.
• Develop a QA/QC protocol to be used for cross comparison of data derived
from different methods.
• Prioritize sample matrices to be analyzed (tissue, whole body, viscera)
• Develop prioritized screening methods:
- low to high sensitivity
- compound specific vs. broad spectrum
- tiered approach
- biological variables; life stage, sex, age, lipids
- methods for various levels of analyst skill, analysis cost
• Basic research leading to improved methods:
- selectivity, verification of compound ID
- sensitivity in various matrices
- cost effectiveness, speed
- multi component analyses
- in situ, real time analyses
- remote transmission and electronic data processing
- computerized QA/QC to ensure data quality targets
Rationale:
Assessing the fate and effects of pesticides in the Gulf of Mexico requires
intercomparable analyses among numerous laboratories. A wide variety of acceptable
methodologies are in use for pesticide analyses in various matrices (water, sediment,
tissue). Differences in protocol and analytical capabilities among these methods lead
to nonreproducible or noncomparable results.
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Even though various agencies have adopted standard methods to address this problem
and various protocols do exist (e.g., AOAC, EPA-500/600, EPA-SW-846, ASTM), a
performance-based protocol is needed as a means to cut across differing
methodologies.
The appropriate method may vary depending on the desired end product for the
specific analytical problem to be addressed.
compound specific (Qualitative vs. Quantitative)
rapid screening
desired sensitivity
specific matrix
level of ecological impact to be assessed (tiered approach)
ancillary data (DO, temperature, salinity, sex, tissue, collection site, season,
time, etc.)
• level of analytical sophistication required
To assure high quality and intercomparison of data, standard protocol must be
followed. Establishing performance-based QA/QC procedures would allow data
derived from different methodologies to be compared based on the performance of the
analysts and not the method use. This protocol also would allow new methods
developed to address speciation, bioavailability, partitioning, transport, etc. to be
evaluated and used to resolve emerging issues.
The high cost of sample collection and analysis cm be off set by the use of volunteer
groups or other professionals of opportunity such as farmers, fishermen, scuba divers,
school groups and volunteers. Strict training and QA/QC protocol designed for such
data collection methods must be established and implemented for data collected in this
manner to be of use.
Additional research needs to be directed toward simplified methods for analysis of
new, unique chemical pesticides such as glyphosate (herbicide) which require special
and costly analytical methods. Development of rapid screening methods
encompassing broad classes of pesticides should be considered a high Priority, as
should the development of proper QA/QC protocol to establish reproducible levels of
detection, precision, and accuracy.
Initiation Activities:
• Standard reference pesticides in reference matrices
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• Interfaces between ecologists and biologists
• Field sampling and sample transport/storage protocol
• Analytical instrumentation (various levels) protocol
Priority Level: 2
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
9. Understanding of Chemical Contaminant Effects on Marine
Mammals and Top Carnivores in the Gulf of Mexico
Research/Information Needs:
Marine mammals, sea turtles and other protected species are high visibility, valued
resources that often represent top carnivores or long-lived species in the Gulf. These
species are not routinely considered in ecological assessments of pesticide impacts.
Data are lacking on toxicity of chemical contaminants or related
biochemical/physiological biomarkers of stress or exposure. The existing data gaps
may presently limit the effective management of these species in the Gulf of Mexico.
Rationale:
Protected species such as marine mammals (e.g., bottle nose dolphin) and sea turtles
(e.g., Kemps Ridley) are unique species to the Gulf of Mexico. There are several
threatened or endangered species in these groups,, because^of the declining or unstable
populations. Additionally, many of these species are long-lived or top carnivores, and
may integrate contaminant exposures in marine ecosystems. Because these are highly
valued, high visibility species in the public, special considerations may be warranted
in environmental assessments of contaminant impacts.
Enhanced understanding of the exposure and dose-response relationships for these
species is necessary to ensure that current pesticide management practices provide
sufficient protection for threatened species. Research is needed to identify baseline
physiological/biochemical conditions and effects of pesticides which can be used as
biomarkers. Results of these efforts would be used to determine the role, if any, of
pesticides in the effective management and protection of these unique organisms.
Identification of anthropogenic pollution sources and pollutant bioaccumulated by
marine mammals or turtles may provide an effective integrated predictor of potential
impacts for top trophic level species. Linkages between contaminant levels in the
lower food chain may compliment predictive assessments used to evaluate health risks
from consumption of contaminated seafood. Additionally, by building a chemical
contaminant and physiological/biochemical biomarker database for the bottlenose
dolphin, environmental managers would have requisite information to better predict
overall biodiversity with respect to the health of threatened or protected species. A
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final product would be a better information base to assist environmental scientists in
diagnosing unusual mortality or morbidity events for these species.
Initiation Activities:
• Necessary items would include: boats for live capture operations; emergency
care/rehabilitation facilities; trained, experienced veterinarians to oversee the live
capture and sampling operations; interactions and consultations with marine
mammals commissions for approval of live capture operations; interactions with
national environmental organizations and state marine mammal stranding
networks; and facilities to conduct contaminant physiological and biochemical
analyses.
• Improved data and knowledge base on chemical contaminants and
physiological/biochemical parameters in endangered and threatened species.
• Interactions and linkage of these data with the ongoing network of rescue and
stranding programs.
• Protection of the biodiversity within the Gulf of Mexico.
Priority Level: 3
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
10. Development and Evaluation of Remediation Strategies for
Contaminated Habitats
Research/Information Needs:
Monitoring programs in The Gulf have indicated the presence of persistent pesticides
in sediment habitats of highly productive areas. In order to ensure complete
ecological recovery and minimize potential food chain contamination problems, these
areas must be remediated to acceptable background levels. There are several
technical and political hurdles that must be overcome in order to develop and
implement a remediation strategy.
• One of the research needs is to determine what agency or program (federal, state,
or private industry) would be responsible for developing these strategies.
• There is a need to evaluate the feasibility of using the remedial approaches
developed and tested in the ARCS (Assessment and Remediation of Contaminated
Sediments) in the Great Lakes.
• There is also the potential for the utilization of biological, chemical, physical, or a
combination approach for clean-up of pesticide-laden sediments.
Rationale:
The clean-up, restoration, and recovery of habitats or resources contaminated by
pesticides may require one or more of the following:
• adaptations of existing remediation technologies used for water, soil, or
sediments contaminated by more conventional pollutants (i.e., petroleum
hydrocarbons, creosotes, metals);
• development of novel treatment technologies that utilize specific pesticide
degradation techniques; and/or
• techniques adapted for minimal habitat disruption.
The Gulf of Mexico contains extensive coastal areas that result in sediment trapping
such as wetlands, submerged sea grass beds, or mud flats. Given the high degree of
biological productivity associated with these depositional habitats, remediation
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technologies that reduce pesticide concentrations, mobility, or bioavailability, the use
of in sita approaches may be preferred over more intrusive methods. Given the long
growing season and warm water temperatures that prevail in the gulf, biologically
based remediation may be particularly effective in degrading pesticide residues.
As a result of high pesticide use practices and the historical use of organochlorine
pesticides in the gulf, there are many sediments and watersheds that have detectable
residues of persistent and bioaccumulative pesticides. In addition to habitats with
historically contaminated sediments, watersheds feeding Gulf estuaries continue to
deliver contaminated sediments and soils. Remediation strategies will be needed to
deal with these continual sources as well as in-place contamination.
Initiation Activities:
Priority Level: 3
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Pesticides Toxic Substances and Pesticides in the Gulf of Mexico
11. Development of an Ecosystem Water Quality Risk Based
Approach for Risk Assessment Using Archived Tissue
Contaminant Data
Research/Information Needs:
Current resource monitoring data provide information on contaminant levels which
may be applied to human health hazard/risk management, but current techniques do
not exist to predict resource impacts to estuarine and marine organisms in the Gulf of
Mexico.
Rationale:
Chemical contaminant levels in fishery organism (molluscan, shellfish, crustacean and
fin fish) constitute the largest data record for the Gulf of Mexico. While chemical
contaminant levels in fishery organism are extremely important in terms of identifying
potential human health hazards/risks, they are not -predictive of potential ecological
impacts. Derivation of "average" in stream water concentrations may be predicted
from existing chemical contaminant residue data in aquatic resources by dividing these
values by published bioconcentration factors (BCFs) for each reported chemical
residue value. These derived "average in stream water concentrations" may then be
divided by existing EPA water quality criteria to develop individual and cumulative
ecological risk estimates. Both acute and chronic ecological risk may be predicted by
this method. The margin of safety between the published EPA acute or chronic water
quality criteria, and the estimated ecological risk estimates may swerve as a predictor
of the potential assimilative capacity for a given geographical area. When these data
are linked with modeling and loading estimates (which may indicate a 1-2 order of
magnitude increase above average conditions), site-specific estimates of habitat
vulnerability to nonpoint source runoff may be assessed and evaluated. Identification
of water quality risk unique to Gulf may be learned. This may be of particular
importance in Gulf of Mexico habitats jointly influenced by pesticide runoff and oil
exploration activities, which may cumulatively impact water quality.
page 76 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Pesticides
Initiation Activities:
Data on contaminant levels in estuarine/marine organisms and literature reviews to
develop published BCF criteria are requisite resources needed. Limited field studies
would be needed to validate derived water quality criteria estimates.
The products would be:
• water quality-based risk assessment estimates of ecosystem health and
• a method for identifying and evaluating cumulative impacts.
Water quality criteria based on reduced bioaccumulation and food chain effects would
provide a degree of protection that takes into account the long growing season along
The Gulf and the Potential for extended inputs or exposures. A similar approach has
been proposed for the Great Lakes Region, but the degree of protection offered by
importing those regional criteria is not known.
Priority Level: 3
September 1993 page 77
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Synthesis and Conclusions Toxic Substances and Pesticides in the Gulf of Mexico
SYNTHESIS AND CONCLUSIONS
The purpose of this workshop was to identify the data and information gaps that,
when filled, will enable the Gulf of Mexico Program to complete a comprehensive
ecological risk assessment for the Gulf of Mexico with regard to toxic substances and
pesticides. The previous sections have summarized the major research needs required
for better understanding toxic inorganic, toxic organic, and pesticide contamination in
the Gulf. These additional research projects will provide essential information for
assessing risks in the Gulf of Mexico. Throughout the workshop, however, several
themes emerged from all three workgroups. These areas represent fundamental
building blocks for an ecological risk assessment. These themes are:
• characterization of exposure • fundamental research
• characterization of ecological effects • continuous chemical and
• pollution prevention and risk reduction biological monitoring
Characterization of Exposure
Characterization of exposure is part of the second phase of ecological risk assessment.
After problem formulation (the first step of ecological risk assessment), the analysis
pi ase develops profiles of environmental exposure and the effects of the stressor.
The exposure profile characterizes the ecosystems in which the stressor may occur as
well as the biota that may be exposed. It also describes the magnitude and spatial and
temporal patterns of exposure. The workgroups identified two areas of exposure
assessment that in their current state were too inadequate to use in a risk assessment
for the Gulf of Mexico: historical information verification and the development of
fate and transport models.
Data Review
In order to ensure that historical data on toxic and pesticide loadings and ambient
concentrations can be used in exposure assessments, data must be verified through a
rigorous data review. Although there are significant data on inputs and contaminant
levels found in water, sediments, and biota tissue (e.g., NOAA Status and Trends,
STORET), all workgroups expressed concern over the reliability of these data. A
page 78 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Synthesis and Conclusions
wide range of procedures--QA/QC, sampling, technical, and analytical-have been
used for all the various data sources available, making it extraordinarily difficult, if
not impossible, to normalize these values and compare them to each other, and across
estuaries. Data contained in some data bases do not contain an assessment of the
reliability of that data. In addition, many data bases do not currently reflect state of
the art analytical methods. All groups critically recommended review of existing data
bases to determine whether data should be used in exposure assessments.
Fate and Transport Modeling
Contaminant transport in the Gulf of Mexico is subject to, and can be dominated by,
extreme and episodic events, such as floods and hurricanes, as well as routine
physical/chemical phenomena such as volitilization, sedimentation, and
photosynthesis. Any attempt to understand the fate and transport of toxic substances
and pesticides must consider these events as well as the influences of the wider
Caribbean. All three working groups recommended that hydrogeologic/fate and
transport models at various scales of resolution be developed that would include not
only these extreme events, but also inputs and effects of the wider Gulf of Mexico
region.
Characterization of Ecological Effects
Characterization of effects is also part of the analysis component of ecological risk
assessment. This phase-defines the quantitative and qualitative relationships between
a stressor and an organism response. The assessment summarizes data on the effects
of the stressor and relates them to the assessment endpoints. Estuarine ecosystems
are subject to a complex and dynamic array of physical, chemical, and biological
interactions. Scientists only have limited understanding of how toxic stressors
influence these interactions and how disturbances at one level of biological
organization are expressed at other levels. They have a limited capability to compare
or predict effects from one species to another and have limited quantitative approaches
for dealing with population, community, or ecosystem comparisons. Assessments
should be extended from single-species approaches for site-specific and media-specific
(e.g., effluent, water column, sediment, biota) situations to a fundamental,
quantitative understanding of exposure-response relationships for larger ecological
units, such as estuaries.
Risk assessment techniques have been used in the past to evaluate the impact or
potential impact of contaminants on coastal environments. A formal process of risk
September 1993 page 79
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Synthesis and Conclusions Toxic Substances and Pesticides in the Gulf of Mexico
assessment or risk analysis is currently used by regulatory agencies to assess such
impacts on human health. And now, regulatory agencies are beginning to see the
need to use a more formal ecological risk assessment process to determine impact on
ecosystems, particularly estuarine systems. For example, EPA's Risk Assessment
Forum is currently testing their ecological risk assessment framework in a New
England estuary.
Preliminary procedures to assess ecosystem condition are presently available. Current
broad-scale assessment programs conducted by NOAA, NMFS, and USEPA in the
Gulf of Mexico provide a focus for future protocol development and endpoint
evaluation. These protocols should then be validated in multiple environments in the
Gulf. The need for developing additional techniques is not as great as the need to
organize existing procedures into general guidelines and protocols applicable across a
variety of Gulf of Mexico estuarine systems. The appropriate assessment design must
include spatial, temporal, and historical considerations and must be configured around
specific testable hypotheses and validated ecological models rather than random
sampling for no directed purpose. The design must be generic to the degree that site-
specific modifications can be implemented. A tiered approach would help ensure that
the strategy meets budget, time, and personnel constraints.
Fundamental Research
Fundamental research is necessary to establish the foundation for each phase of
ecological risk assessment. Each panel identified a number of specific items that need
additional fundamental research. Some of these needs were unique to the panel's
particular contaminant category (e.g.? inorganic, pesticide, organic), while others
applied to all chemical classes. Within the area of inorganic contaminants, there is a
continuing need for additional basic research into the fundamental processes that drive
chemical speciation and ultimately influence metal bioavailability and toxicity. For
pesticides and organics, there is a need for fundamental research to evaluate the
resilience of aquatic plant and animal communities that are repeatedly challenged by
episodic inputs and a need for a better understanding of the processes that govern the
dynamics of trophic level chemical transfer.
Continuous Chemical and Biological Monitoring
Cutting across the range of contaminant classes was the need for identification of
baseline values for the biological, chemical, and physical parameters that will be used
to assess the health of the Gulf ecosystem. Inherent to the process is the identification
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Toxic Substances and Pesticides in the Gulf of Mexico Synthesis and Conclusions
of unaffected habitats from which to obtain "normal" or background values. A
logical approach would be to emulate the establishment of Long Term Ecological
Research Sites (LTERs) along the Gulf of Mexico as developed by the National
Science Foundation (e.g., Hubbard Brook, NH). These areas could be used for
comprehensive evaluation of baseline values that are representative of ecosystem
health.
Current monitoring and assessment approaches in the Gulf of Mexico depend on
collection, analysis, and reporting of discrete samples of water, sediment, and biota.
Time lags of months and years are not uncommon before collected data are examined
to assess environmental problems. These methods are time consuming, costly, and
can fail to yield results because the inputs of toxic substances and pesticides are
diverse and dynamic. It was the consensus of the workshop participants that the Gulf
of Mexico Program represents a unique opportunity to nurture research and
development capabilities for versatile and field deployable analytical methods and
instrumentation to support multi-compound monitoring programs.
The Gulf of Mexico area includes research community agencies and laboratories that
have developed sophisticated technologies with potential applications to real time
environmental monitoring. For example, NASA has developed a host of active and
passive remote sensing technologies which could potentially evaluate physical,
chemical, and biological properties of the bays and estuaries of the Gulf of Mexico on
a real-time basis. The Department of Defense's remote sensing capabilities and
acoustical sensing, in combination with pattern recognition algorithms, may have
direct applications to assessing ecological health. Advances in microelectronic
telemetry and data storage and analysis make the use of living organisms as
biosensors of the environment a feasible option. Because this type of instrumentation
depends on the technological capabilities of university, commercial, and government
facilities, workshop participants recommended that the Gulf of Mexico Program
establish, nurture, and promote the development of technologies leading to the
capability to monitor environmental quality on a continual basis.
Reducing Risk: Pollution Prevention
The input of toxic substances and pesticides into the Gulf of Mexico and the continued
persistence of in-place materials are an important element of ecological risk. Altering
toxic chemical and pesticide use practices could help reduce that ecological risk.
This change may result in reduced application rates, formulations, or changing
chemicals for pesticide applications. Changes in processes and treatments preventing
a continued discharge of organic or inorganic chemicals may reduce ecological risk
September 1993 page 81
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Synthesis and Conclusions Toxic Substances and Pesticides in the Gulf of Mexico
from these materials. Due to the inherent uncertainty associated with risk assessment
and management, all the workgroups agreed that one of the most logical areas to
focus is pollution prevention.
Best Management Practices (BMP) can be implemented to reduce chemical input into
the Gulf by changing application rates, constructing buffer zones with wetlands to
prevent runoff, and altering application times and chemicals. Risk reduction can be
accomplished by using pesticides with high degradation rates and high potency at low
concentrations, requiring less material input.
Control of point source discharges of toxic chemicals may be altered using best
available technologies to minimize wastes and limit mass emissions of toxic
contaminants. It was a consensus recommendation of the workshop participants that
regulatory agencies should extend incentives for pollution prevention, such as
reducing loadings or the decreased discharge of significant chemicals. Industries may
institute process, raw material, or housekeeping changes when there is an incentive
for these offsets.
Conclusions
Although many of the workshop recommendations focuscon fundamental research on
the fate and effects of toxic substances and pesticides, participants recognized the need
for research on tools that will eventually integrate this information.
Risk assessment requires integration of information about stressors and effects.
Ecological resources in the Gulf of Mexico contend with a variety of natural and
anthropogenic stressors. Although considerable information exists regarding the
spatial and temporal distribution of stressors in the Gulf of Mexico, understanding the
relative impacts of these stressors requires decision support tools. Scientists and
resource managers should develop and utilize expert systems containing data based on
stressor distribution over space and time, distribution of ecological resources along
the Gulf of Mexico, and hydrological and ecological models at various scales of
resolution. These expert systems or interactive data bases should allow for the
integration of multiple data layers in a geographic context. Development of a GIS
capability supporting the comparative risk assessment goal of the Gulf of Mexico
Program was a consensus recommendation of the workshop.
Figure 5 arrays the recommendations contained in this Research Strategy in a
ecological risk assessment framework. This is to provide both a context for
understanding the role of the recommendations in risk assessment and a tool for
page 82 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Synthesis and Conclusions
highlighting any remaining barriers or gaps that impede completion of an ecological
risk assessment for the Gulf of Mexico.
The columns represent the three phases of risk assessment. The rows represent
procedural steps and tools that are used to complete the risk assessment. Although
the risk assessment process is iterative, this diagram is intended to depict a general
process framework. Within this framework, workshop themes-highlighted in bold
italics on the matrix—have touched upon both procedural tools and risk assessment
stages.
Many of the recommended research activities are placed appropriately in the risk
assessment paradigm. These activities typically cover more than one step in the risk
assessment process and more than one analytical tool. These placements are not
placed rigorously in all of these areas, but rather are arrayed to depict the general
areas covered.
Major overall workshop recommendations included: assessment of existing data for
proper QA/QC, standardized methods, and gaps; development of standard
methodologies and assessment tools, including remote monitoring tools; development
of Gulf-specific models; and establishment of baselines and criteria for healthy Gulf
ecosystems. Specific needs identified by the toxic inorganics workgroup included the
establishment of development of bioaccumulation and hydrogeologic models,
development of metal speciation and bioavailability models, and development of
quantitative techniques for integration of effects and exposure data. Specific needs
identified by the toxic organics group focused en development of predictive and
diagnostic ecological effects tests, assessment of available data on anthropogenic
inputs, and development of a site-specific estuarine/ecosystem quality criteria for
target pollutants. The pesticides workgroup specifically targeted the identification of
problem pesticides, the interpretation and application of tissue residue data, and the
understanding of repeated short-term exposure events in the Gulf.
Ideally, these recommended research activities, when coupled with existing
knowledge, will provide a complete framework within which to initiate an ecological
risk assessment for the Gulf of Mexico.
September 1993 page 83
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Synthesis and Conclusions Toxic Substances and Pesticides in the Gulf of Mexico
Figure 5. Risk Assessment Framework
page 84 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Bibliography
BIBLIOGRAPHY
Capuzzo, J.M. and M.N. Moore. 1986. "Acute and Chronic Effects of Toxic
Chemicals in Aquatic Organisms." la Toxic Chemicals and Aquatic Life:
Research and Management. Symposium Program and Abstracts. September 16-
18, 1986. Seattle, WA.'
Gulf of Mexico Program. 1993. Toxic Substances Action Agenda for the Gulf of
Mexico.
Overstreet, R.M. 1986. "Aquatic Pollution Problems, Southeastern U.S. Coasts: n.
Biological Aspects." la Toxic Chemicals and Aquatic Life: Research and
Management. Symposium Program and Abstracts. September 16-18, 1986.
Seattle, WA.
Pait, et al. 1992. "Agricultural Pesticides in Coastal Areas: A National Summary."
Pait, A.S., D.R.G. Farrow, J. A. Lowe, and P.A. Pacheco. 1989. The National
Coastal Pollutant Discharge Inventory: Agricultural Pesticide Use in Estuarine
Drainage Areas: A Preliminary Summary for Selected Pesticides. National
Oceanic and Atmospheric Administration. Strategic Assessment Branch.
Rockville, MD.
Pastorok, R.A., P.N. Booth, and L.G. Williams, date unknown. Puget Sound fact
sheet.
Texas A&M Research Foundation-Geochemical and Environmental Research. 1989.
Third Annual Report: Analyses of Bivalves and Sediments for Organic Chemicals
and Trace Elements. January 1989. Submitted to U.S. Department of
Commerce, NOAA National Ocean Service, Rockville, MD.
U.S. Department of Commerce. 1987. "Chlorinated Pesticides and PCBs in Oysters
(Crassostrea virginica) and Sediments from the Gulf of Mexico, 1986-1987."
NOAA National Status and Trends Mussel Watch Program. Submitted Mar.
Environ. Res.
U.S. Environmental Protection Agency. 1992. Framework for Ecological Risk
Assessment. Risk Assessment Forum. USEPA 630/R-92/001. February 1992.
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U.S. Environmental Protection Agency. 199la. Toxics in the Community: National
and Local Perspectives. Pesticides and Toxic Substances (TS-779). USEPA
560/4-91-014. September 1991.
U.S. Environmental Protection Agency. 199Ib. Toxic Substances A Pesticides Fact
Sheet. Gulf of Mexico Program. John C. Stennis Space Center, MS.
Wade, T.L., J.L. Sericano, J.M. Brooks, and B.J. Presley. 1991. 'Overview of the
First Four Years of the NOAA National Status and Trends Mussel Watch
Program." Draft. Texas A&M University. College of Geosciences.
Geochemical and Environmental Research Group. College Station, TX.
page 86 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico
Appendix A
APPENDIX A: LIST OF WORKSHOP PARTICIPANTS
Steering Committee
Richard H. Pierce (Chairman)
Mote Marine Laboratory
1600 Thompson Parkway
Sarasota, FL 34236
William W. Walker (Co-Chairman)
Gulf Coast Research Laboratory
708 East Beach Drive
Ocean Springs, MS 39564-7000
Linda Anderson-Camahan
U.S. EPA. Region IV
Office of Policy & Management
345 Courtland Street, NE
Atlanta, GA 30365
Kenneth L. Dickson
North Texas State University
Institute of Applied Sciences
P.O. Box 13078
Denton, TX 76203
Philip B. Dora
Shell Development Corp.
3333 Highway 6, South
Houston, TX 77251-1380
Donald R. Grothe
Monsanto Company
800 N. Lindbergh Blvd.
St. Louis, MO 63 167
Foster L. Mayer
U.S. EPA Environmental Research Lab
Island
Gulf Breeze, FL 32561
Raymond G. Wilhour
U.S. EPA Environmental Research Lab
Sabine Island
Gulf Breeze, FL 32561
Participants
Last Name
First Name
Affiliation
Adams
Allen
Bailey
Benson
Buckler
Calder
Carr
Casseri
Clark
T inHa
Bill
Kim
Tom
Bill
Denny
Fred
Scott
Nicholas
Jim
EPA, Region 4
ABC Labs
Recorder Mote Marine Laboratory
U.S. EPA
University of Mississippi
U.S. Fish & Wildlife Service
Florida Department of Environmental Protection
U.S. Fish & Wildlife Service
Occidental Chemical Corporation
Exxon Biomedical Sciences, Inc.
September 1993
page 87
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Appendix A
Toxic Substances and Pesticides in the Gulf of Mexico
Conway
Cramer
Daniels
Deardoff
Dickey
Dickson
Dickson
Dillon
Dixon
Dora
Dow
Duke
Fox
Heimlich
Henry
Holtzman
Jahncke
Lewis
LyUe
Mayer
McCaffrey
Metz
Nava
Overton
Pierce
Rossomando
Scott
Sherblom
Smith
Walker
Wilhour
Windom
Winger
Wise
Wolfe
Dick
Greg
Carol
Thomas
Robert
Gary
Ken
Tom
Kellie
Phil
Roxanne
Belinda
Catherine
John
Mike
Seymour
Mike
Mike
Julia
Sonny
Bruce
Simone
•Smiley'
Ed
Rich
Marybeth
Geoff
Paul
Darryl
Bill
Ray
Herb
Parley
Lloyd
Steve
Union Carbide
U.S. Food and Drug Administration
U.S. EPA- Gulf Breeze
International Paper Company
U.S. Food & Drug Administration
Ciba Geigy, Inc.
University of North Texas
U.S. Army Corps of Engineers
Mote Marine Laboratory
Shell Development Company
Florida Department of Environmental Protection
Gulf of Mexico Program - Public Education
U.S. EPA-Office of Water
AMS
Recorder, Mote Marine Laboratory
Brookhaven National Laboratory
DOC/NOAA/NMFS
U.S. EPA
Gulf Coast Research Laboratory
U.S. EPA, Gulf Breeze
AMS
Florida Institute of Technology
Texas Department of Parks & Wildlife
Louisiana State University
Mote Marine Laboratory
AMS
National Marine Fisheries Service, Charleston
Recorder, Mote Marine Laboratory
Florida Department of Agriculture
Gulf Coast Research Lab
EPA-Gulf Breeze
Skidaway Institute
U.S. Fish & Wildlife Service
Gulf of Mexico Program
Florida Department of Environmental Protection
page 88
September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico
Appendix B
APPENDIX B: WORKGROUPS
PESTICIDES
TOXIC INORGANICS
Jim CUrfc (Chair)
Bill Beoioo (Co)
Tom Bailey
Greg Cramer
Gary Diekioa
Tom Dillon
RoxanaeDow
Catherine Fox
Mike Jahncke
•Smiley* Nava
Rich Pierce
GeoffScott
Darryl Smith
Mike Henry
John Heimlich
Exxon Biomedical Sciencei, Inc. BUI Adams (Chair) ABC Labi
University of Mississippi Denny Buckler (Co) U.S. Fuh and Wildlife
EPA Fred Calder Florid* DEP
U.S. FDA
Ciba Geigy. Inc.
U.S. Army Corpa of Engineer!
Florida DEP
EPA -Office of Water
DOC/NOAA/NMFS
TX Department of Parka A Wildlife
Mole Marine Laboratory
NMFS. Charleaton
FL Department of Agriculture
Recorder. Mote Marine Lab
AMS
KeUieDUon
Mike Lewis
Sonny Mayer
SimoneMeB
Bill Walker
HerbWiadom
Parley Winger
Steve Wolfe
Kim Allen
Marybeth Rouomando
Mote Marine Laboratory
EPA
EPA-Gulf Breeze
FL Institute of Technology
Gulf Coaei Research Lab
Skidaway Institute
U.S. Fish & Wildlife Service
Florida DEP
Recorder, Mole Marine Lab
AMS
TOXIC ORGANICS
SYNTHESIS & SUMMARY
Ed Overton (Chair)
Linda Anderson-Cai
Scott Carr
Nicholas Caaseri
DickConway
Carol Daniels
Thomas Deardoff
Robert Dickey
Phil Dora
Seymour Holtzman
Julia Lytle
RayWilhour
UoydWise
PaulSherblom
Bruce McCaffrey
Louisiana Slate University
nahan (Co) EPA. Region 4
U.S. Fish ft Wildlife
Occidental Chemical Corporation
Union Carbide
EPA-Gulf Breeze
International Paper Company
Food * Drug Adminiatration
Shell Development Company
Brookhaven Research Laboratory
Gulf Coast Research Laboratory
EPA-Gulf Breeze
Gulf of Mexico Program
Recorder. Mote Marine Laboratory
AMS
Ken Dickion (Chair)
Phil Dora (Co)
Bill Benson
Denny Buckler
Sonny Msyer
Rich Pierce
Bill Walker
Ray Wilhour
University of North Texas
Shell Development Company
University of Mississippi
U.S. Fish and Wildlife
EPA-Gulf Breeze
Mote Marine Laboratory
Gulf Coast Research ' ***
EPA-Gulf Breeze
Bruce McCaffrey AMS
Marybetb Rosaomando AMS
September 1993
page 89
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Appendix C Toxic Substances and Pesticides in the Gulf of Mexico
APPENDIX C: WORKSHOP AGENDA
WORKSHOP ON RESEARCH NEEDS FOR TOXIC SUBSTANCES
IN THE GULF OF MEXICO
AGENDA
Monday - August 23
11:00 - 1:00 REGISTRATION - Mote Conference Center
1:00 PLENARY SESSION
Introductions: Richard Pierce, Conference Chairman, Director of Research, Mote
1:15 Welcome: Kumar Mahadevan, Exec. Director, Mote; COM Regional Marine
Research Program
1:30 Keynote Speaker Lloyd Wise. Deputy Director
EPA Gulf of Mexico Program
2:00 Overview, Toxicants: Ray Wilhour, Deputy Laboratory Director; Subcommittee
EPA, Gulf Breeze Environmental Research Lab.
2:15 Chemicals, What Where When: Catherine Fox, EPA, Risk Assessment and
Management
2:45 BREAK
3:00 Research Case Study: Seymour Holtzman, Brookhavcn National Assessment:
Radionuclides and Formation Waters
3:30 Living Aquatic Resources at Risk: Geoffrey Scott, NOAA
NMFS Charleston Lab
4:00 Comparative Risk Assessment: Ken Dickson, University of North Texas
4:30 Workshop Goals: Ken Dickson, Workshop Facilitator
5:00 Plenary Session Ends
6:30 Social and Buffet Dinner, Mote Chickee.
page 90 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Appendix C
Tuesday - August 24
8:00 Continental Breakfast at Mote
8:30 Convene three Working Sessions
10:15 BREAK
10:30 Plenary Session Review
12:00 Lunch (Provided)
1:30 Reconvene Working Sessions
4:30 End day's Working Sessions: Synth. & Summ. Comm. review progress
7:30-9:30 Evening Working Sessions
Wednesday - August 25
8:00 Continental Breakfast at Mote
8:30 Reconvene Working Sessions for final recommendations
10:15 BREAK
10:30 Final Plenary Session to present Working Session's recommendations
12:00 Workshop Ends
1:30 • 4:30 Synthesis and Summary Committee, Session Chairs & Consultant
September 1993 page 91
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Appendix D Toxic Substances and Pesticides in the Gulf of Mexico
APPENDIX D: ADDITIONAL PUBLICATIONS
Other Gulf of Mexico Program Toxic Substances and Pesticides Committee
Publications
"Impact of Toxic Substances and Pesticides on Nearshore Gulf of Mexico: A
Preliminary Comparison (Toxicity Indices) of Twenty-Five Estuarine Drainage
Systems Based on Releases of Toxics From Industrial and Municipal Sites and
Pesticide Run-Off From Agricultural Operations in 1989"; by Jeri Brecken-Folse
and Maureen G. Babikow, Technical Resources, Inc., and Dr. T.W. Duke,
Consultant, under contract to USEPA Gulf Breeze, FL.
"Estuarine Assessment and Contaminant Problem Identification"; NOAA Technical
Memorandum NMFS-SEFSC-, Summary of a workshop held in Biloxi, MS, April
23-25, 1991. Mayer, F. L., Thomas W. Duke, and William W. Walker (eds.).
1992.
"Evaluation of Gulf of Mexico Sediment Inventory"; by Jeri Brecken-Folse and
Maureen G. Babikow, Technical Resources, Inc., and Dr. T.W. Duke,
Consultant, under contract to USEPA Gulf Breeze, FL. Draft 1993.
"Gulf of Mexico Toxic Substances and Characterization Report"; by John Brabeck
and Jeri Brecken-Folse.
"Proceedings of the Workshop on Toxics and Pesticides Action Plans", F. L. Mayer
and P. Bass, Toxic Substances and Pesticides Subcommittee, Gulf of Mexico
Program. 1990.
"Proceedings of the Workshop on Toxics and Pesticides Monitoring Data for
Regulatory Purposes", F. L. Mayer and R. R. Dow, Toxic Substances and
Pesticides Subcommittee, Gulf of Mexico Program, 1989.
"Proceedings of the First Meeting", F. L. Mayer and R. R. Dow, Toxic Substances
and Pesticides Subcommittee, Gulf of Mexico Program, 1989.
"Proposed Action Items Beginning FY91", F. L. Mayer and P. Bass, Toxic
Substances and Pesticides Subcommittee, Gulf of Mexico Program, 1990.
page 92 September 1993
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Toxic Substances and Pesticides in the Gulf of Mexico Appendix 0
The above documents axe available from:
The Gulf of Mexico Program Office
Bldg 1103, Room 202
Stennis Space Center, MS 39529-6000
September 1993 page 93
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