**Statement of Mark Myers**

**Director**

**U.S. Geological Survey**

**Department of the Interior**

**Before the**

**House Committee on Government Reform**

**\
Oversight Hearing on \"Ova-Pollution in the Potomac: Egg-Bearing Male
Bass and Implications for Human and Ecological Health\"\
\
October 4, 2006**

**Introduction**

Thank you Mr. Chairman for the opportunity to present testimony on the
Department of the Interior's (Department) science regarding intersexual
characteristics of fish in the Potomac River. My name is Mark Myers, and
I am the Director of the U.S. Geological Survey (USGS).

The USGS is a federal science agency within the Department that conducts
research to understand the interrelationships among earth surface
processes, ecological and biological systems, and human activities. The
USGS does not conduct this science alone. We partner with other federal
and state agencies, tribal governments, and non-governmental
organizations, including human health agencies or academics, when a
comprehensive human health assessment is required.

The USGS has collected data on endocrine disruption in fish and measured
concentrations of endocrine disruptor chemicals in many rivers
throughout the United States. For 12 years, the USGS has engaged in
research activities concerning fish health assessments in the Potomac
and Shenandoah Rivers. Fish that possess intersexual characteristics are
not limited to the Chesapeake Bay Watershed. The USGS has found such
fish in the Mississippi River, the Rio Grande and Colorado Rivers, the
Columbia River, the Missouri River, the Las Vegas Wash and many other
locations throughout the country.

My testimony today will cover the following:

-   The fish health problem in the Chesapeake Bay and other rivers in
    the Nation;

-   The role of USGS and our partners investigating the concerns;

-   Current research into the potential causes of intersexual
    characteristics and endocrine disruption; and

-   The role of our sister agency at the Department, the U.S. Fish and
    Wildlife Service, on this issue.

I will conclude my testimony with a brief discussion of the additional
information that is needed to help managers develop solutions for this
problem.

**Identification of the Issue**

In recent years, there have been a number of fish-health problems within
the Chesapeake Bay and its watershed that are associated with changing
water quality and habitat conditions. One of our major findings is the
presence of intersexual characteristics in smallmouth and largemouth
bass in the Potomac River.

The term "intersex" or intersexual characteristics describes a range of
abnormalities in which both male and female characteristics are present
within the same fish. Intersexual characteristics are most commonly
described as the presence of female germ cells, which are the precursor
to mature eggs, within a male reproductive organ and/or malformed
reproductive ducts.

The occurrence of intersex fish has been related to chemicals, often
termed endocrine disruptors, that affect the reproductive system.
Endocrine disruptors are chemicals that interfere with the natural
balance of hormones that regulate development, reproduction, metabolism,
behavior, and the internal state of living organisms. Occasionally these
abnormalities can be noted externally but most often the main
reproductive organs must be examined under a microscope for diagnosis of
intersexual characteristics. The presence of this abnormality or
intersexual characteristic has been used as an indicator of exposure to
estrogenic chemicals and has been documented in a variety of wild fish
species in a number of rivers and estuaries around the Nation (*e.g.*,
Florida, Colorado, California), as well as other countries, including
the United Kingdom, the Seine-Maritime Bay (France), the Mediterranean
Sea, and China.

**Role of the U.S. Geological Survey**

The USGS provides science to help understand the environment, including
the factors affecting fish health. The information is used by the U.S.
Fish and Wildlife Service (Service), whose role with regard to this
issue is discussed in more detail below; the U.S. Environmental
Protection Agency (EPA); and other state and federal partners to better
manage and restore fish, wildlife, and their habitats and to protect
human health. The risk to humans from fish with intersexual
characteristics is currently unknown.

The specific fish-health investigations in the Potomac Watershed that
led to the discovery of intersexual characteristics in fish were
conducted as part of the USGS efforts on the Chesapeake Bay Watershed.
USGS programs and partners, including the Service, the Virginia
Departments of Game and Inland Fisheries and Environmental Quality, the
Maryland Department of Natural Resources, and the West Virginia Division
of Natural Resources (WV DNR), have contributed to this work on fish
health issues in the Chesapeake Bay drainage.

**Recent Assessments of the Chesapeake Bay Watershed**

In 2003 and 2004, in response to fish kills and increased observations
of external sores and wounds on smallmouth bass and other species, WV
DNR and USGS initiated fish-health assessments at selected sites in the
South Branch of the Potomac River. Samples were collected, and pieces of
all tissues, including reproductive organs, were removed for evaluation.
During this time period, 16 out of 24 sampling events showed more than
25 percent of the male bass possessing intersexual characteristics.
Sampling also indicated seasonal differences in the ratio of male bass
possessing intersexual characters. Fish sampled in the spring months had
a 25-40 percent higher occurrence of intersexual characteristics than
those sampled during the summer months.

In 2005, through collaboration among USGS, the Service, the Virginia
Departments of Game and Inland Fisheries and Environmental Quality, the
Maryland Department of Natural Resources, and the WV DNR, sampling was
expanded to additional sites in the Shenandoah and Potomac watersheds
for determination of the extent of the intersex problem. During the late
summer/early fall of 2005, samples were collected at sites farther
downstream in the Potomac, specifically to look at areas associated with
intersexual characteristics. These included wastewater treatment
outflows; major fish kill sites; and other drainage sites for use as
possible background sites. A map of sampling sites is shown in Figure 1.

These preliminary findings suggest that intersexual characteristics in
fish are widespread throughout the Potomac and Shenandoah Rivers, but
are at a much lower incidence in other sampled rivers in West Virginia.

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Figure 1. Map of sampling sites for largemouth and smallmouth bass
within the Potomac River Watershed. Fish symbols indicate sites at were
fish were collected for determination of intersexual characteristics.

**Potential Causes**

Potential causes of intersexual characteristics in fish include chemical
contamination and changes in the temperature regime or habitat. Current
research on intersexual characteristics has related numerous chemicals
to reproductive effects in fish. These chemicals, often termed
"endocrine disruptors," include previously banned chemicals, such as DDT
and chlordane, natural and anthropogenic hormones, herbicides,
fungicides, industrial chemicals, and an emerging group of chemicals
including personal care products and pharmaceuticals that may act as
endocrine disruptors in fish as well as other organisms. Potential
sources of these endocrine disruptors include agricultural, as well as
individual use of herbicides and pesticides, human waste (discharges
from wastewater treatment facilities and individual home septic
systems), animal wastes that may reach the aquatic environment through
runoff, leachates from landfills, and even atmospheric deposition.

Laboratory studies have indicated that the chronic effects of exposure
to low levels of these chemicals can result in negative reproductive
effects on zebrafish and fathead minnows. In addition, laboratory
studies of fathead minnows, medaka, rainbow trout, common carp and
zebrafish have shown other negative effects on reproductive activity by
endocrine disruptors. Some results indicate that exposure to
environmental contaminants may be affecting both growth and reproductive
physiology of individual white sturgeon in the Columbia River. However,
we have not been able to conclude from field studies, like the Potomac
River study, that endocrine disrupting chemicals have impacts on wild
fish populations. In addition, the interactive effects of multiple
endocrine disruptors on aquatic organisms are unknown.

A limited amount of information is available on the distribution of
these endocrine disruptors in the Chesapeake Bay and its major river
basins. During 1992-1996, the USGS conducted extensive sampling of the
Potomac and the Susquehanna River Basins. Chlordane, DDT, and PCBs were
detected in streambed sediment and aquatic tissues in the Potomac Basin.
Sediment from over one half of the sites contained concentrations of
these chemicals that posed an intermediate probability of having adverse
effects on aquatic life.

In 1999 and 2000, the USGS undertook a nationwide study to provide
information on the occurrence of a larger group of chemicals and
endocrine disruptors that may be entering the Nation's streams through
wastewater. The USGS sampled streams at 139 sites across the Nation,
including one site in the Potomac River basin. The samples were analyzed
for 95 different emerging contaminants including human and veterinary
drugs, hormones, detergents, disinfectants, insecticides, and fire
retardants. At least one of these chemicals was found in 80 percent of
the streams, with mixtures of the chemicals occurring at 75 percent of
the sites. Most common groups detected were steroids, nonprescription
drugs and insect repellent. Only 14 of these chemicals have human health
advisory criteria and measured levels rarely exceeded any of the
standards or criteria. However, little is known about the majority of
the chemicals found in the samples or the effects of these chemicals
when they are mixed together.

The USGS has also been active in developing methods to measure
hormonally active or endocrine disrupting chemicals in water sediment
and tissue, as well as in developing integrative samplers such as
Semi-Permeable Membrane Devices (SPMDs) and Polar Organic Chemical
Integrative Samplers (POCIS). These new methods are used to assess the
environmental occurrence of these chemicals. The USGS has published a
significant number of journal articles on the environmental occurrence
of endocrine disruptors that provide useful information to researchers
in determining the concentrations and mixtures of these chemicals for
laboratory studies.

Although the effects of endocrine disruptors can be replicated in the
laboratory under controlled conditions using synthetic hormones or other
chemicals, it has not been possible to demonstrate a cause of the
intersexual characteristics in the field. Laboratory studies that
discern the causative mechanisms for endocrine disruption are also
underway at several USGS Science Centers. USGS is developing new
molecular and other techniques to determine the causative agents of
multiple stressor situations.

Research by other scientists around the world has shown that endocrine
disrupting chemicals in aquatic environments affect various fauna, from
mussels to fish to birds. Some of the aspects of this issue are being
addressed by the European Commission and the U.S. Food and Drug
Administration to determine the potential risks of human and veterinary
drugs on the environment.

**Additional Information is Needed**

There is a need to further document the extent of intersexual
characteristics within the Chesapeake Bay and other watersheds.
Identifying the chemicals that are impacting the fish, and their
sources, fate, and transport will help managers develop solutions for
the problem. The USGS is currently conducting a study to address some
aspects of the issue in the Shenandoah Valley of the Potomac River
Basin. What is learned there may be applied and expanded to other areas
and other watersheds.

To help coordinate federal research activities related to endocrine
disruption in the environment, the USGS is leading the planning effort
for an interagency workshop in February 2007 at the USGS Headquarters in
Reston, Virginia. This workshop is being organized under the Office of
Science and Technology Policy and the Council on the Environment and
Natural Resources. Eight federal agencies will be participating in this
workshop. The major goals are to review the current knowledge about
endocrine disruption in the environment, what type of research and
studies each agency is currently doing and planning in this area, and
most importantly, to develop specific opportunities for collaboration
between agencies. The workshop will involve a variety of federal
scientists and managers in every aspect of endocrine disruption,
including developing methods to detect Endrocine Disrupting Chemicals
(EDC) in the environment; basic research on how they affect fish and
wildlife; developing methods for monitoring and identifying sources; and
different ways the discharge of EDCs can be minimized or removed from
the environment.

Given our current scientific understanding of intersex in fish, the
areas in which USGS science can make a valuable contribution include
determining:

-   What effects these endocrine disruptors have on the ability of fish
    to reproduce, thrive and sustain populations in the wild;

-   What aquatic organisms are being affected (e.g., are only benthic
    feeders or fish that lay eggs in the sediment affected or are other
    aquatic organisms at risk), and the implications for the aquatic
    ecosystem;

-   What chemicals and other stressors are implicated in these effects;

-   How to improve our ability to predict causes of endocrine disruption
    in the field;

-   The consequences of these effects at the population and ecosystem
    levels; and

-   Potential causes of intersexual characteristics in fish, including
    chemical contamination, and changes in the temperature regime or
    habitat.

**Role of the U.S. Fish and Wildlife Service**

At the request of the Committee, this testimony also provides
information developed by the Service concerning the work it is carrying
out regarding this issue.

The Service's Environmental Contaminants Program is responsible for
protecting the nation's fish and wildlife from environmental
contaminants through scientific study, mitigation, education and habitat
cleanup. The Service has been involved with studying contaminant effects
on fish and wildlife since its earliest days, but the Environmental
Contaminants Program (Program) really began to take form in the 1950s,
when increasing awareness of pollution problems spurred the American
public to demand action.

The Service's Program includes contaminants specialists stationed at
more than 75 locations around the country. Service contaminants
specialists specialize in detecting toxic chemicals; addressing their
effects; preventing harm to fish, wildlife and their habitats; and
[removing toxic
chemicals](http://www.fws.gov/contaminants/Issues/Superfund.cfm) and
[restoring
habitat](http://www.fws.gov/contaminants/Issues/Restoration.cfm) when
prevention isn\'t possible. They are experts on [oil and chemical
spills](http://www.fws.gov/contaminants/Issues/OilSpill.cfm),
[pesticides](http://www.fws.gov/contaminants/Issues/Pesticides.cfm),
[water
quality](http://www.fws.gov/contaminants/Issues/WaterQuality.cfm),
hazardous materials disposal and other aspects of pollution biology. The
Program\'s operations are integrated into all other Service activities
and the Service\'s contaminants specialists often work in partnership
with other agencies and organizations which have come to rely on our
expertise.

In 1991, the Program began investigating the potential reproductive
effects of endocrine disrupting contaminants on wildlife with studies on
the endangered Florida panther, polar bears and their prey. To date, the
Program has funded and participated in more than 23 studies that
specifically looked at the effects of endocrine disrupting contaminants
on wildlife across the country. Many of these studies have been directly
associated with endangered species recovery actions or threats to the
recovery of listed species. These studies typically included management
recommendations for the removal of threats from contaminants or other
corrective actions to alleviate the impacts of endocrine disrupting
contaminants on wildlife.

Some examples of the geographic and taxonomic extent of the studies
include: river otters (Oregon); fish, alligators, and panthers
(Florida); fish and barn swallows (lower Mississippi River --Louisiana);
fish and reptiles (Arizona); fish and wildlife (Nevada); polar bears and
eiders (Alaska); sturgeon (middle Mississippi River - Illinois,
Missouri, Iowa); mussels and paddlefish (Ohio); common loons (Maine);
terns and cormorants (New York); cormorants (Michigan); fish (Delaware,
Maryland, Virginia); and amphibians (Texas). All of these investigations
involved wildlife and habitat sampling to determine how the wildlife
were being exposed to the disruptors and provided suggested management
actions to alleviate impacts of endocrine disrupting contaminants on
wildlife.

Recently, the Program initiated a campaign with the American Pharmacists
Association (APhA) and a myriad of other partners including
pharmaceutical manufacturers, the Food and Drug Administration, DEA,
Environmental Protection Agency, American Veterinary Association, AMA,
PhRMA, Water Environment Federation, U.S. Geological Survey, US
Pharmacopeia, Pfizer, Walgreens, AstraZeneca, and the Association of
Fish and Wildlife Agencies to develop recommendations and outreach
strategies regarding the disposal of unused and unwanted
pharmaceuticals. One of the objectives of this campaign is to raise
public awareness about disposal options for prescription drugs as a
means to minimize the introduction of chemicals into the environment.

**Service Involvement on the Potomac River Intersex Study of Bass**

As discussed above, the Service's Chesapeake Bay Field Office
Contaminants Program participated in a study to assess endocrine
disruption in bass at five locations in the Potomac River Watershed. In
coordination with the states of Virginia and Maryland, and including the
USGS, the Service selected two sites each on Conococheague Creek and the
Monocacy River, Maryland and one on the Potomac River near the Blue
Plains wastewater treatment plant, Washington, DC. In 2005, the Service
collected data to determine if:

-   Sewage treatment plants were releasing detectable concentrations of
    endocrine disrupting compounds into these water bodies;

-   Male bass exposed to endocrine disrupting compounds had altered
    concentrations of vitellogenin, the protein precursor for egg
    production; and

-   Male bass exposed to endocrine disrupting compounds are exhibiting
    intersex characteristics.

Today, the Service is working with the USGS to determine if intersex,
altered vitellogenin concentrations, or altered hormone ratios can be
induced in caged hatchery raised bass deployed in Monocacy River and
Conococheague Creek compared to a control group of bass at the National
Fish Health Research Laboratory in Kearneysville, West Virginia**.**

Final chemical analyses and field and laboratory data have not been
completed. However, preliminary results indicate that between 80 to 100
percent of the male bass collected in the Mononcacy River and
Conococheqgue Creek exhibited intersexual characteristics. More field
collections were completed in mid-June 2006 and all samples are
currently being analyzed at the laboratory. A final report is expected
by Spring 2007.

In sum, Interior bureaus have been carrying out and will continue field
collections in the Potomac River watershed. One of our major findings is
the presence of intersexual characteristics in smallmouth and largemouth
bass in the Potomac River. We do not know the full extent of this
phenomenon throughout the entire watershed, as studies to date have been
relatively small scale, have involved a single species, and were located
near obvious potential sources of endocrine disrupting chemicals. In
future years, comprehensive watershed evaluation may be necessary. There
is more work to be done, but we are eager to continue our collaborative
efforts with federal, state, and private partners to finds ways to
better understand the impacts of endocrine disrupting chemicals on the
Nation's fish and wildlife resources.

Thank you, Mr. Chairman, for the opportunity to present this testimony.
I will be pleased to answer questions you and other Members of the
Committee might have.

References

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Ator, S.W., J.D. Blomquist, J.W. Brakebill, J.M.Denis, M.J. Ferrari,
C.V. Miller and H. Zappia. 1998. Water quality in the Potomac River
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Daughton, C.G. and T.A. Ternes. 2006. Pharmaceuticals and personal care
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