United States Environmental Protection Agency
                         CBP/TRS 59/91
                           May 1991
Surface Microlayer Sampling
  Results for the Chesapeake
                          Bay


                  Spring 1988
                    Chesapeake
                          Bay
                      Program

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Surface Microlayer Sampling Results
   for the Upper Chesapeake Bay:
             Spring 1988
         Printed by the U.S. Environmental Protection Agency
                  for the
              Chesapeake Bay Program

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           Prepared by:


        Hermann Gucinski
  Anne Arundel Community College
          Ronald Preston
U.S. Environmental Protection Agency
          Robin J. Laird
U.S. Environmental Protection Agency
   Chesapeake Bay Program Office

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                            ABSTRACT

     An exploratory study was conducted during the spring of 1988
to examine the surface microlayer  zone  of the Chesapeake Bay for
the presence of contaminants, to measure  ambient toxicity of the
microlayer, and to  characterize the microlayer biotic community.
This study was also conducted to compare  the seasonal variations
of the contaminant concentrations to a previous surface microlayer
investigation  conducted during  the autumn  of  1987  (U.S.  EPA,
1988a). This investigation  included: chemical analysis scans for
pesticides, organics and metals;  neuston collection and community
composition; and, screening acute  toxicity testing using Menidla
frer.yl.llna.
     Trace  quantities  of  contaminants   (pesticides,  organics,
metals) were detected  in the microlayer.   In several cases, the
concentrations were greater  than  detected in the  water column.
However,  the  values  for  the  spring  1988  sampling  generally
indicated less contaminant concentration in the surface microlayer
than was found in  previous sampling during the late summer of  1987.
The  neuston  community  was  dominated  by the   genera  Bosmina,
Eurytemora,  and  Acartia.     Other organisms  observed  included
Gammarus,  piaphanosoma,  Daphnia and  fish  eggs.   The screening
toxicity tests of  surface microlayer samples with the silver minnow
 (Menidia Jberyllina) did not produce acute toxic  responses.
     The field conditions and  observations indicated a general lack
of coherent surface films.   The  low concentrations of microlayer
contaminants found  in this  study correlate well  with the presence
or absence of such  microlayer yslick'  occurrences.

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                        ACKNOWLEDGEMENTS

     Analytical support was obtained through contract laboratory
services of the Industrial Technology Division,  Office of Water
Regulations and Standards, U.S. EPA; field sampling and neuston
analysis by the Environmental Center, Anne Arundel Community
College, Annapolis, Maryland; the screening toxicity tests were
conducted by the Biology Laboratory staff, Environmental Services
Division, Region III,  U.S. EPA; a portion of the field sampling and
metal analyses were performed by Lenwood Hall and his staff of the
Applied Physics Laboratory, Johns Hopkins University.
     We would  also like to thank Richard Batiuk  of the U.S. EPA
Chesapeake Bay Program Office and Ellen  Horvath, Computer Sciences
Corporation,  for  their continuous  efforts  in   finalizing  this
document for publication.

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                        TABLE OF CONTENTS


                                                             Page
ABSTRACT	  i

ACKNOWLEDGEMENTS	 . i i

     LIST OF TABLES 	 V

     LIST OF FIGURES	 vi

     INTRODUCTION 	 1

     METHODS AND MATERIALS 	 1

           Field Sampling Design and Sampling Locations 	 1

           Surface Microlayer Sample Collection and Handling  ... 2

           Surface Tension and Pressure Analyses	7

           Chemical Analyses  	 9

           Biological Analyses	 9

             Toxicity Testing  	 9

             Neuston Collections 	 11

           Surface Microlayer Sampler Design 	 12

     RESULTS AND DISCUSSION  	 12

           Surface Microlayer Contamination	 12

             Physical Analyses  	 12

             Chemical Analyses  	 22

           Biological Results 	 25

             Toxicity Tests  	 25

             Neuston Analyses  	 25

     CONCLUSIONS 	 29

     BIBLIOGRAPHY 	 31
                               iii

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                            APPENDICES


APPENDIX A:  Freeman Surface Microlayer Sampler
             Design Specifications 	,	 A-l


APPENDIX B:  Henidia beryllina Toxicity Testing:
             Survival, Physical and Chemical Data 	,,... B-l


APPENDIX C:  Neuston Species and Abundance Data 	 C-l
APPENDIX D:  List of Organic Compounds Scanned for
             in the Surface Microlayer and
             Bulk Water Samples 	 D-l


APPENDIX E:  List of Pesticides Analyzed for the
             Surface Microlayer and Bulk Water Samples 	 E-l
                                iv

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                          LIST  OF TABLES
                                                             Page

Table 1.  Surface Microlayer Sample Collection
           Stations in Upper Chesapeake Bay 	   3

Table 2.  Surface Microlayer/Bulkwater Sample
           Collection Stations in Northern
           Chesapeake Bay - Metal Analyses Only 	  5

Table 3.  Analytical Methods Used for Contaminant
           Analyses of Surface Microlayer and
           Bulk Water Samples	  8

Table 4.  Summary'of Physical Observations made
           during Surface Microlayer Sample Collection	  14

Table 5.  Organic Compounds Detected in the Surface
           Microlayer and Bulk Water Samples	  23

Table 6.  Pesticide (Tributyltin) Detected in the
           Surface Microlayer and Bulk Water Samples 	  23

Table 7,  Metals, Dibutyltin, and Tributyltin (TBT)
           Concentrations in the Surface Microlayer and
           Bulk Water Samples 	  24

Table 8.  Summary of Menidia beryllina Toxicity Tests
            Results	  26

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                         LIST OF FIGURES
                                                             Petge
Figure 1.  Surface Microlayer/Bulk Water Sample Collection
            Stations in Upper Chesapeake Bay 	  4

Figure 2.  Surface Microlayer/Bulk Water Sample Collection
            Stations in Upper Chesapeake Bay -
            Metal Analyses Only 	  6

Figure 3.  Freeman Surface Microlayer Sampler 	 13

Figure 4.  ATR Infrared Spectrum from the
            Choptank River Surface  Microlayer 	 16

Figure 5.  ATR Infrared Spectrum from the
            Choptank River Surface  Microlayer
            (Deionized Water Leach) 	 17

Figure 6.  ATR Infrared Spectrum from the
            Susquehanna River Surface Microlayer  	 19

Figure 7.  ATR Infrared Spectrum from the
            Susquehanna River Surface Microlayer
            (Deionized Water Leach) 	 20

Figure 8.  Zisman Contact Angle Plot -
            Choptank River Station  	 21

Figure 9.  Zisman Contact Angle Plot -
            Susquehanna River Station	 21

Figure 10. Neuston in the Surface Waters
            of the Choptank River Station 	 27

Figure 11. Neuston in the Surface Waters
            of the Potomac River Station 	 27

Figure 12. Neuston in the Surface Waters
            of the mid-Chesapeake Bay Mainstem Station 	 28

Figure 13. Neuston in the Surface Waters
            of the Susquehanna River Station 	 28
                                VI

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INTRODUCTION

     Analyses of surface microlayer samples  in previous investiga-
tions have revealed elevated levels of contaminants  in the surface
microlayer of the Chesapeake Bay compared to the  rest of the water
column  (bulk water).  An exploratory study conducted in the autumn
of 1987  (U.S. EPA, 1988a) found detectable or higher levels of 24
pesticides, 14 aromatic hydrocarbons, 22 saturated hydrocarbons and
organotin  in the  surface  microlayer  at  6  upper  Chesapeake Bay
stations.   The relatively  high contaminant levels found  in the
Potomac  and Susquehanna rivers  during the  study  suggested that
these sites be revisited. The mixed contaminant loads found at the
mid-Chesapeake  Bay and  the  Choptank River  sites  also suggested
repeat sampling.  The selection of these stations for analysis was
an  attempt  to  verify  the  seasonal  variations   in  microlayer
contaminant concentrations, and to evaluate the  threat that might
exist in important living resource habitat areas.  Another recent
study  in the  Chesapeake Bay  (Hardy et. al.,   1987)   also  found
elevated levels of organics contaminants and metals  in the surface
microlayer.

     The microlayer sampling survey described here was designed to
follow up these earlier  studies.  The survey objectives were to:

       Test  the hypothesis  that higher  concentrations of  some
       pesticides are  expected  during spring application periods
       compared to autumnal runoff  periods,  leading to increased
       surface microlayer contamination;

       Analyze  the  spring surface  microlayer  samples  for  other
       organics and metals contamination;

       Sample the  neuston  community and  identify  species  poten-
       tially exposed to surface microlayer  contamination;  and,

       Explore  the  potential   toxicity of  collected  surface
       microlayer samples to finfish.
METHODS AND MATERIALS

Field Sampling Design and Station Locations

     The survey  was designed to maximize  the  information gained
from  the few  stations  sampled.    Sample Quantity  constraints,
dictated by available  resources,  allowed for collection of fewer
bulk water (10 cm below the water column surface) than microlayer
samples.  Characterizing potential  impacts required that station
selection include important living resource areas as well as zones

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with the  potential for high  contamination.   Four  stations  were
selected - Susquehanna River at  Havre de Grace, mid-Chesapeake Bay
at Matapeake, Choptank River  at Cambridge,  and the Potomac River
at Hedge Neck -  all  located in  northern  Chesapeake Bay (Table 1,
Figure 1).  At two of the  stations  - Hedge Neck and Havre de Grace
- bulk  water samples were  also collected concurrently  with the
surface microlayer samples.

     The Havre de  Grace station represented the input point from
the large Susquehanna River drainage area,  with the potential for
contaminants from agricultural and  urban sources within"the basin.
The  Matapeake station  represented  an  area  that  typifies  the
conditions  in  the upper  Chesapeake  Bay  mainstem.   The  Choptank
River at Cambridge station represented  an upper Bay tributary with
important living  resource habitats.   The Potomac  River  at Hedge
Neck station,  immediately downstream of the  urban Washington DC
metropolitan area, is representative  of a potentially contaminated
area.  These stations were a subset of stations previously sampled
for surface microlayer contamination  in the  fall of 1987  (U.S. EPA
1988a).

     In addition to the metal analyses conducted from these four
stations,  metal analyses were also conducted for a set of surface
microlayer/bulk water samples collected from six other Chesapeake
Bay locations: three  on the Potomac  River,  one on the Elk River,
one on the Sassafras River and one  on the Susquehanna River (Table
2, Figure  2) .   The  Johns  Hopkins  University,  Applied Physics
Laboratory, performed the sampling and analyses.
Surface Microlayer Sample Collection and Handling

     The surface microlayer samples and neuston tows were sampled
over a zone that was determined by towing speed and duration.   To
minimize  tidal current  effects,  tows  were bi-directional,  and
typically  covered  a  distance  of  50  to  60  meters.    Physical
observations were made simultaneously with the surface microlayer
sample collections, and the neuston tows performed last.

     The  collection  of  surface  microlayer  samples  required  a
sampler  towed by  an  outrigger from  the beam  of a  small  craft
(Figure 3).  For speed and  efficiency, a  small craft was propelled
by  an  electric motor  in an  upwind or  crosswind  direction when
possible, with the sampler towed outside of the boat's wake.

     The  microlayer  drum  sampler  was   used  with the  following
protocol: the drum was washed with detergent, rinsed with sampling
water,   and  allowed  to  turn for  10  minutes prior  to  sample
collection  in order  to  complete the  rinsing  and equilibration

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      Figure 1.  Surface Microlayer and Bulk Water Sample
                  Collection Stations in Upper Chesapeake Bay
                   Station 8
                Susquehanna River
                (Havre de Grace)
        Station 12
    Mid-Chesapeake
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Potomac
 (Hedge Neck)   -
  Station 11
Choptank River
, (Cambridge)

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      Figure 2.  Surface Microlayer and Bulk Water Sample
                 Collection Stations in Upper Chesapeake Bay
                           —Metal Analyses Only
                      Susquehanna River
              3
Potomac River,  . \
Middle  ^  ^+£&
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VA
                                                      	Elk River
                                                      * Sassafrass River
              Potomac River,
                  • MD

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cycle.  A half-gallon  glass  sampling bottle (with a teflon lined
cap) was used for all collections.  Aliquots were taken for metals,
volatile organics, tributyltin  (TBT),  and bioassay analyses from
the first bottle.  Separate bottles were used for the organics and
pesticide scans.  All  samples were stored on  ice until they were
taken to the lab by air-express  or  local transportation within the
holding time  specified in  the analytical  methods references (see
Table 3) . This  same collection procedure was maintained throughout
the sampling effort.

     Sample collections were accompanied by physical observations
of: surface tension using the Adam spreading oil technique  (Adam,
1937);  Germanium  prism  dips  for  characterizing  the  organic
composition of  the  microlayer   (Gucinski,  1981  and Baier et al.,
1974);  sea  surface  and  air temperature  (bucket thermometer);
salinity  (refractometer);  windspeed  (hand  held anemometer),  and
wind direction  (small  boat compass).   Table 6  contains a summary
of the physical  observations  made during surface microlayer  sample
collections.

     The collection  times for  surface microlayer sampling were
extremely  long   when  the  concentration  of surfactants  (surface
active agents) was too low to produce measurable surface pressure
changes at  the air-water interface.  When sample  collection periods
exceeded 10 minutes for the collection of  two liters of microlayer
water,  the  field  crew  maximized  these   collection  efforts  by
following windrows of  bubbles because they indicate the zones of
convergence  where  microlayer thickness   and  enrichment may  not
reflect truly average sea surface conditions.
Surface Tension and Pressure Analyses

     Chemical bonds of dominant organic molecules were identified
using Attenuated Total  Reflection   (ATR)  Infra-Red spectroscopy
(Gucinski et  al.,  1981;  Baier, 1974; Harrick,  1967).   Optically
flat, trapezoidal prisms of Germanium (50x20x1 mm) were vertically
lowered  and  retrieved  through  the  interface,  relying  on  the
Langmuir-Blodgett transfer of surface  active  substances to  the
Gesubstratum.   The  method  is  sensitive to about 5 nanograms of
sample  and  does not  appear  selective   for   "wet"  surfactants
(Gucinski et al., 1981).

     Surface  tension  was  measured  after  Adam   (1937), in  which
mixtures of  mineral oil of zero  spreading pressure  and  dodecyl
alcohol of high intrinsic  spreading pressure are calibrated for
several spreading pressure  ranges.  Dropper application of mixtures
with increasing alcohol strength quickly yielded a point of visible
droplet spreading against the ambient surfactant  pressure, allowing

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a quick  determination of a  narrow range of  sea-surface tension
values.

     By measuring  the contact angles  of a series  of ultra-pure
liquids of known surface tension,  one may plot the cosine of these
angles against the liquid's  surface tension.  The intercept at the
cos 00 = 1 axis  of the least square fit  of the data gives a numeric
value termed  the critical tension or  critical  surface  energy by
Zisman  (1964) who, with  coworkers, developed  the technique.   The
concept provides an empirical description that closely relates to
the substrate's surface energy, and has proven to be an' excellent
predictor of wetability and adhesion.
Chemical Analyses

     Chemical analyses  on the surface microlayer  and bulk water
samples were  performed for the following  categories  by contract
laboratories:

     Analyses               Laboratory

     Organics               Midwest Research  Institute
     Pesticides             Colorado  State University
     Metals/Tributyltin     Johns   Hopkins  University,  Applied
                              Physics Laboratory

     The methods  and  quality  assurance  procedures used for these
analyses are described in the method references provided in Table
3.  The isotope  dilution gas chromatography/mass spectrophotometry
(GC/MS)  
-------
daily renewal aliquots) kept  cool  (at  four degrees centigrade to
minimize deterioration) during the test period and used as source
for the daily renewal.   This option was chosen because of the lack
of resources required to collect daily surface microlayer samples
at four widely separated geographical locations.  Also, relatively
large volumes of surface microlayer samples (over four liters) were
difficult to obtain due to  the  lack  of surface forming "slicks."
Therefore, the volume of a sample did not permit the chronic test
to be run for the routine seven days; the results of the four-day
test are valid for measuring acute response.

     The static renewal test  protocol  recommends  using 7-11 day-
old  silverside minnows  (Menidia beryllina).    When the  sample
collection  and testing  began  for  the  toxicity  response  test,
however,  only  19-23 day-old  fish were  available  in sufficient
numbers for the designed test.  While  the  protocol authors theorize
that Menidia Jberyllina  may be less sensitive to contaminant effects
as the fish age beyond  the post-larvae  stage, such comparable data
for 19-23 day old fish  are not available.  Cultured test organisms
are less variable  in many ways than  'wild'  fish  and, therefore,
even though  the test  fish  were 12  days  older  than recommended,
their potential response to controlled test conditions was presumed
more beneficial than not conducting  this screening toxicity test
at all.

     A sample of laboratory  source control water (15 ppt salinity)
was obtained from the U.S. EPA's Gulf Breeze Laboratory.  A control
was set up with each group of samples because the age of the fish
changed as the study progressed.  Comparisons between control and
exposure tests should only be made among samples set up on the same
day.  Using commercial  artificial sea salts, the salinities of the
microlayer and  bulk  water  samples were  adjusted  to the salinity
range in which the test organisms were acclimated.  A control was
set up on May 10,  1988  using these artificial salts to demonstrate
that these salts do not adversely affect the survival and growth
of Menidia Jberyllina.

     Menidia. beryllina was chosen because it is  one of the species
identified  in  the standardized  EPA  method  manual  for  marine
toxicity tests.  It also is  an estuarine  species that inhabits the
Chesapeake Bay.  The Menidia  beryllina used for these tests were
obtained from  the  U.S. EPA's Gulf Breeze Laboratory.   They were
shipped  air freight on May  9,  1988  and arrived at  the mobile
laboratory the next day.  The  fish were cultured in the laboratory
control water  at  23-25 degrees centigrade  with a  salinity of 15
ppt.  On the day that  testing was  initiated (May 10,  1988), they
were 19 days old.   The remaining  fish were held in culture water
to be used in the  samples set up  on  May 12, and May 14, 1988 and
were  21  and 23  days  old,   respectively.   While being  held,  the
                                10

-------
Menidia Jbisryllina were fed concentrated brine shrimp nauplii twice
daily.

     After  the  water samples  arrived  at the  laboratory,  the
temperatures were adjusted up to the test temperature (24 degrees
centigrade +/- 2).  The salinities were then adjusted to within 5
ppt salinity of  the  culture/holding  water.   The  pH,  temperature,
salinity and dissolved oxygen were measured in each test solution.
The dissolved  oxygen was measured in  one of the  replicate test
containers every day thereafter for the duration of the test.

     Each sample was set up  in triplicate in 125 X  65  mm glass
containers with  500 ml of test solution in each.   For the samples
set up  on May  10 and 12, ten fish were  placed in  each replicate
for a total  of 30 per sample.   Due  to a  reduced  supply of fish
during  the  testing  period,  only six  fish were placed  in each
replicate of the samples  set  up on May 14  for  a  total of 18 fish
per sample.

     One hundred microliters of concentrated brine shrimp nauplii
were dispensed to each replicate every morning.  The test organisms
were allowed to  feed before  the  containers were cleaned.   Each
replicate test chamber was cleaned daily by siphoning the water and
any debris out of it,  filtering the  water through  a  brine shrimp
net and returning the  water to  the  test  container.    The test
organisms were then fed again.

     All tests were  terminated  after  four days  of testing.   The
tests set  up  on May  10 and 12  were  terminated  in the mobile
laboratory.   The  samples  set up on May 14 were transferred  from the
mobile laboratory to the U.S. EPA's Wheeling Laboratory on May 16
and  terminated  on May  18.    Results  of  the   control  exposure
indicated no adverse effect of this transfer.  At termination, the
test organisms were euthanized and preserved in 70% alcohol.  The
fish from each replicate  were dried and weighed to determine their
mean dry weight.   The survival and weight data were analyzed using
Dunnett's Procedure.

                     Neuston Collections

     The neuston  population density,  composition and diel variation
were all sampled from the same sampling stations  using dual nets -
a  neuston  net immersed   5-10  centimeters  during  tows  and  a
subsurface net sampling at the 30-50 centimeters  depth.

     The dual net consisted of two rectangular-mouth  (0.56 X 0.17
meter) zooplankton nets with a mesh size of 200 micrometers.  Ten
minute  tows  were  made  at  a boat   speed  of  one  nautical  mph,
retracing a  marked  path or  towing  in a  large  circle  to  avoid
                               11

-------
current bias in the estimated sampling volumes.  The towed distance
was 315 meters <0.17 nautical mile)  and the sampling volume of the
partially  immersed  upper  netf  was  7.6 cubic  meters while  the
lowered net sampling volume was 25.8 cubic meters.

     Nighttime collections were made no sooner than 3.5 hours after
sunset, and were generally completed  at least two  hours before
sunrise.  Daytime collections rarely began before 10:00  a.m., or
generally  at  least  4.5  hours  after  sunrise,  and were always
completed at least three hours before sunset.

     Identification was made by  counting aliquots  of the sample in
a Durrel trough using  aliquot  volumes of 5  -  10  milliliters and
increasing  the  volumes   until   consistent   concentrations  for
identified species were obtained.  Dissecting scopes and low power
(X40)  inverting microscopes were  used  as  required.   The major
literature  sources for  taxonomic  identification  include  Ward and
Whipple (1966); Versar,  Inc.  (1987), and  Lippson and Moran (1974).

Surface Microlayer Sampler Design

     The surface microlayer sampler (Figure 3)  was constructed to
provide the Chesapeake  Bay Program with an  evaluated device for
surface microlayer  sample operations.    This device incorporates
modifications of existing surface microlayer  samplers to improve
the design of the sampler in the following areas:

     - collection  of  sample  volumes  sufficient  for   chemical
       analysis;
     - high collection efficiency;
     - shallow, nominal/sampling depth;
     - reasonably light weight;
     - ease of repair and disassembly; and,
     - facility for use from small boats.

     Appendix A gives the design specifications and notes.
RESULTS AMD DISCUSSION

Surface Microlayer Contamination

                        Physical Analyses

     The  presence of either  naturally occurring  surfactants or
surface active  contaminants is  reflected  in the observed surface
pressure changes  (Table 4) from the nominal surface tension value
of 72.4 mN/m  (milli Newton per meter) of freshwater at 20 degrees
centigrade.     Surface  pressure  measurements,  using  the  Adam
                                12

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spreading oils which rely on surface pressure sensitivity, did not
vary more than 1 mN/m  from the  nominally clean value.  A surface
pressure change greater  than 1  mN/m correlates with sufficiently
close  molecular  packing  of  surfactants  to produce  interfacial
effects such as capillary wave  suppression;  it also produces the
appearance of surface slicks  (Katsaros et al.f in press; Huhnerfuss
et  al.,  1985).    Thus,  a  measured spreading  pressure  of  9.25
indicates the  clean surface tension of 72.4 mN/m had dropped to
63.15 mN/m.

     In the spring 1988  sampling effort,  few surface slicks were
observed; the  majority  appeared as windrows,  bands  of  foam or
bubbles, with only  a narrow zone of obvious capillary wave damping.
The  highest  surface pressure  of 9.25  mN/m  was  recorded  at the
Susquehanna site at giving a nominal  sea surface tension of 63.2
mN/m.  By comparison, in the autumn  1987 sampling  effort, the same
stations gave  slick surface pressures  as high as  16 mN/m,  with
slicks observed at  all but two of the sites  (data were missing at
two  other  sites)   (U.S.   EPA,  1988a).    Slick  surface  pressures
averaged 7.5 mN/m.   In both the  spring 1988 and the autumn 1987
sampling efforts, the non-slick values  were never lower than 0.83
mN/m.

     We interpret  the  findings  as follows: when no deviations in
surface  tension  are found  (e.g.  72.4  mN/m at  20  C) ,  surface
pressure is  zero,   and the water surface  is essentially  free of
surface-active contaminants.   Low surface pressure (e.g. values
less than 1 mN/m),  indicates the presence of natural or man-made
surfactants in very low  concentrations,  insufficient to produce
even a layer one molecule  thick  (see, for example, Adamson 1974).
Our measurements,  and  the work of others  (Baier et.  al., 1974),
have shown  that  biogenic  surfactants   are ubiquitous  on natural
waters, typically at low concentrations.  Higher surface pressures
indicate higher  surfactant concentrations at  the interface, and
these  may  be toxic,  anthropogenic  surfactants,  or more likely,
biogenic materials that in turn have a high potential for trapping
or adsorbing potentially toxic contaminants (Hardy,  1987 and Hardy
et. al., 1987b, 1987c).

     The presence of organic substances  at the air-water interface
is  further  verified by  two infrared analyses  done on Germanium
prism dips at the Choptank and Susquehanna stations. Figures  4 and
5 show the infrared spectrum of the surfactants recovered, analyzed
by attenuated total reflection (ATR)  unprocessed,  and after gently
leaching with high purity deionized water,  respectively.   The
leaching removes soluble components,  especially salts.   Figure 4
highlights 5 peaks.  These are:

     - the broad peak centered at 3350 I/cm indicating  the presence
                               15

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       of both bound water and molecules having an N-H bond;

     - a  peak produced  by methyl  and CH2  groups of  aliphatic
       hydrocarbons, occurring  free or bound  as side  chains  of
       larger molecules;

     - a peak reflecting atmospheric C02 in the sample chamber of
       the  spectr©photometer,   a  sign of  sensitive  instrument
       performance;

     - the broad, noise  peak(s)  centered  at  1660 I/cm 'reflecting
       the presence  of amide bonds  found in proteins  and their
       breakdown products; and,

     - the peak centered  at 1310  I/cm  which  is produced by bonds
       both of the  sulfate radical and the hydroxyl groups bound
       in polysaccharides.

     The removal by the peaks at 3350 and 1310 I/cm indicated these
constituents  were  not  firmly  bound  and partially  water soluble.
What  remains,  likely  a   significant  component of the  surface
microlayer, is protein-derived material and some hydrocarbons.  The
latter are most  probably man-made inputs  (e.g.  fuels  etc.),  for
these bands are rarely  seen at that strength in waters remote from
human  influence  (see Baier,  1974;  Gucinski  et. al.,  1981;  and,
Sieburth, 1983).

     Figures 6 and 7 contain similar information with the following
differences. The hydrocarbon signature is weaker, while the protein
related peaks are more distinctly defined.  Moreover,  all three
peaks  -  hydrocarbon,  protein-like,  and possible polysaccharide-
like - are changed minimally by leaching the sample,  indicating low
solubility,  and  suggesting large  molecular  size.    Finally,  the
remaining peak  at 3300 I/cm after  leaching  correlated well with
the  presence of  amide  bonds,  further confirming proteinaceous
material to be present.
       *
     Figures  8 and 9 further confirm the presence of a microlayer
organic matrix,  as shown by contact angle  analysis.  The intercept
of  the Zisman Plot  least squares  fit gives  a  critical surface
tension of  21.8  mN/m for the Choptank data  (Figure 8),  and 29.4
mN/m  for  the Susquehanna  data  {Figure 9) .   The former value is
consistent with one obtained in  spreading  a film mixture of glyco-
protein  and  a  little  oil onto  the prism.    The  latter  value,
somewhat  higher,  suggests a less  coherent and less intact film,
shown  by  the changes  seen upon leaching.  Both sets  of contact
angle data were taken after the prism had been leached and analyzed
by infrared scans.  These  data  indicate that small  concentrations
of natural surface-active  substances are present at the air-water
                               10

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interface even in  the  absence of slicks.  The potential  to trap
other substances  including toxic contaminants exists.  The absence
of  well-defined  slicks  of moderate to  high spreading  pressure
during   our   sampling   suggests   that   enrichment   of   trapped
contaminants under these conditions is only moderate at best.

                          Chemical Analyses

     Over 300 organic compounds were scanned for  (Appendix D), but
only four  compounds were  detected  in  microlayer and  bulk  water
samples.   These compounds were three low molecular weight solvents
and a  plasticizer  (Table 5) .    The autumn 1987  study  (U.S. EPA,
1988a)  detected  a  larger  number of organic compounds including
saturated and aromatic hydrocarbons.  These same compounds were not
detected during the  spring 1988 survey.   Sixteen pesticides were
detected  (Table  6)  in  trace  quantities  out  of  the  79  screened
(Appendix E) by GC/MS.   The autumn 1987  study  (U.S.  EPA,  1988a)
detected  a  greater variety  of  pesticides  at  slightly  higher
concentrations than the present study.

     The  results   of the  metals  analyses  (Table  7)  indicated
concentrations of several metals in the surface microlayer samples
exceeded the U.S.  EPA marine  or freshwater water quality chronic
values.   While the microlayer  itself  is not  'water,'  its  close
association to the water column justifies comparing the measured
concentration to these chronic values.

     The  following marine  chronic values were  exceeded in the
microlayer at stations  in  the Elk,  Sassafras  and the Susquehanna
rivers: copper -  2.9 ug/1;  lead - 5.6 ug/1 and nickel - 8.3 ug/1).
The  zinc marine  chronic  value  (86 ug/1)  was  exceeded in the
Sassafras River.

     The freshwater chronic values were exceeded  in the microlayer
for the following:  copper  (12 ug/1) at two of the Potomac River's
three  freshwater  locations;   lead  at  all three  Potomac  River
freshwater locations; and  zinc  at two  of the  three Potomac River
freshwater locations.   The aluminum analytical results were high
for the Potomac (middle  station), Elk , Sassafras and Susquehanna
stations.   These  values exceed  the water quality  criteria for
freshwater organisms.   Depending on hardness and  pH,  the values
reported here are  potentially capable  of producing toxic effects
on aquatic life.

     The  butyltin  concentrations  (Table  7)  were much less than
those observed in  the exploratory studies conducted in the autumn
1987 study (U.S. EPA, 1988a) .  Several of the values  from the spring
1988 study are in the range reported to produce sublethal effects:
.015 ug/1 for dibutyltin (DBT) and .016 ug/1 for  tributyltin  (TBT)
                                22

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-------
in the Matapeake;  .071 ug/1  for DBT  and .009  ug/1 for TBT in the
Choptank; .010 ug/1 DBT and  .028 ug/1 TBT in the Susquehanna.
Biological Results

                         Toxicity Tests

     The Menidia  beryllina toxicity tests were  terminated after
four  days because  insufficient  volumes  of  surface  microlayer
samples  were obtained.    The results  of these tests  (surface
microlayer and bulkwater samples  for four stations) are summarized
in Table 8 and fully listed in Appendix B.

     No mortality with  larval Menidia beryllina was observed in any
of the ambient water samples.   The control exposures (Gulf Breeze
water and an  artificial sea salt water)  also recorded high survival
(100% survival in nine exposures,  89%  survival  in one exposure).
The four-day  growth rate response parameter (final mean weight) was
not  significantly different  in  any  of  the sample  tests  when
compared to  the  sample set controls.   The growth  rate response
parameter in  the endpoint of the standardized chronic test protocol
is designed  for a seven-day period.   Insufficient sample volumes
precluded completion of the seven day chronic test, and therefore,
the four-day test results record an acute toxicity response.

                          Neuston Analyses

     The results of  the neuston analyses are summarized by station
in Figures  10-13 and  fully  listed in Appendix  C.    The neuston
concentration  (number  of  organisms per cubic meter)  and percent
abundance for the top 5 cm and for a 20  cm interval sampled between
the 30 and 50 cm water depth are listed for each station.

     Both day and night tows were made to better characterize the
diel differences.   The  values reported as  the  averages  of two
replicated tows  (with  the  exception of the mid-Chesapeake Bay at
Matapeake  station where  a top  tow sample  was  not  collected).
Unfortunately, the nighttime neuston samples for  the Potomac River
at Hedge Neck station  were invalidated due to  a labeling error.

     The nighttime  total  organism  density exceeded the daytime
density at all  stations,  as  did the  density of  the  single  most
abundant  species.    Nighttime  total   organism   density  exceeded
daytime values by as little as a factor of two at the Susquehanna
station,  up   to  a  factor  of  50  at  the  mid-Chesapeake  Bay  at
Matapeake station.  One might  expect greater organism densities at
the lower depth compared to the surface layer in daytime and this
is borne out  at all  stations.   It is not clear whether a nighttime
                              25

-------
               Table  8. Summary of Menidia berylllna Toxicity Test Results
Sample

Gulf Breeze
Control
Sea Salt
Control
Choptank River
 at Cambridge
 Bulk water

Choptank River
 at Cambridge
 Microlayer

Gulf Breeze
Control
Sueguehanna River
 at Havre de Grace
 Bulk water

Susquehanna River
 at Havre de Grace
 Microlayer

Mid-Chesapeake Bay
 at Matapeake
 Bulk water

Mid-Chesapeake Bay
 at Matapeake
 Microlayer

Gulf Breeze
Control
Potomac River
 at Hedge Heck
 Bulk water

Potomac River
 at Hedge Heck
 Microlayer
Beginning
Test Date

 5-10-88
 5-10-88
 5-10-88
 5-10-88
 5-12-88
 5-12-88
 5-12-88
 5-12-88
 5-12-88
 5-14-88
 5-14-88
 5-14-88
                                                      Total  Number  of
                                                   Surviving Organisms
Rep.        	1

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C

 A
 B
 C
Day
	 1
10
10
10
10
10
8
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
6
6
6
6
6
6
6
6
6
Day
	 2
10
10
10
10
10
8
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
6
6
6
6
6
6
6
6
6
Day
	 3
10
10
10
10
10
8
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
6
6
6
6
6
6
6
6
6
Day
	 4
10
10
10
10
10
8 '
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
€
6
6
6
6
6
6
e
6
Percent
Survival
100
100
100
100
100
89
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
                                          26

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reversal is expected, yet  a  clearly  evident  case was observed at
the Choptank River  at Cambridge station.  Here  a single species
Gammarus sp., accounted  for the high density (97%  abundance) in the
surface layer at night,  although fish eggs were also more abundant
than at subsurface depths.

     At a  number of  sites,  several  species occurred  in greater
abundance within the  surface layer compared  to  the deeper layer,
even if that species did not dominate  the total population density.
For example, at the Potomac  River  at Hedge Neck station, Bos.mi.na
sp.  (a cladoceran)  and Eurytemora  sp.  (a copepod) occurred  in
greater numbers in the  surface  layer,  while  the total  population
density was driven by the  slightly greater abundances  of Acarfcia
sp. (a copepod) and barnacle nauplii in the subsurface layer.  At
the mid-Chesapeake Bay  at Matapeake  station, Acartia  sp.,  mysid
shrimp, and barnacle nauplii  were more abundant below the surface,
but Eurytejnqra sp.  was more dense  within the surface  layer and
Diaphanosoma sp. (a cladoceran) , and Gammarus sp.  (an amphipod) and
fish eggs  were more  abundant within the surface layer.   At the
Susquehanna River at Havre de Grace station, only Daphnia sp. were
more dominant  in the surface  layer  compared  to  the  subsurface
volume sample in this work.

     The greater abundance of some zooplankton species in or near
the surface microlayer, especially at night, along with the high
abundance of a  few species  assemblages in that zone at other times,
suggest highly dynamic behavior  in these populations.  Our data are
too sparse to  allow  deductions about  variables that  shape the
zooplankton density at any one level.  Certainly  vertical motility
plays a role,  as do physical mixing processes.   But the sum total
of the effects  suggests that contact with the  microlayer as part
of the diel changes is likely for some fraction  of these animals.

     Copepods,  cladocerans,  and amphipods  are  important prey for
fishes and shellfish of resource value.  These species may directly
assimilate  potential  toxicants  when the  surface microlayer  is
contaminated.   No knowledge  has come to our attention concerning
the possibility of increased  grazing by these opportunistic species
in slick-covered enriched  areas.

CONCLUSIONS

     The  absence of  coherent  surface  films or slicks and the
infrequency   and  low   concentration   of  surface   microlayer
contaminants found in  this  spring 1988 sampling correlate well with
the  autumn 1987  higher   "slick"  abundance and higher  surface
microlayer  contaminant  loading.   This  correlation  supports the
hypothesis  that  biogenic  surfactants  form a pollutant  trapping
matrix.   No data have  been  found that allow prediction  of the
                               29

-------
frequency, distribution,  and coherence of  film or the  trapping
potential they represent.

     The toxicity test results agree with the organic and pesticide
analyses - no observable  toxic  responses  with low concentrations
of  contaminants.    Several metal  concentrations  (copper,  lead,
nickel and zinc) exceeded the marine water  quality criteria chronic
values.   These  chronic  values were based on  the  lowest observed
effective  concentration  and,  therefore,  observed concentrations
near these values would not necessarily produce  direct  acute or
short-term responses. A broader scoped sample and analysis design
is required  for verification of the observed variability  of the
surfactants and their potential effects.
                               30

-------
                           BIBLIOGRAPHY

Adam, N.K.  1937.  A rapid method for determining  the  lowering of
tension  of  exposed  water  surfaces,  with  some  observations  of
surface tension of the sea and inland waters. Proc. Royal Soc. (B)
122:134-139.

Adamson,   A.W.      1967.      Physical   Chemistry  of   Surfaces.
Interscience, New York, pp. 747.

Baier, R.E., D.W. Goupil,  S. Perlmutter, R. King.  1974.  Dominant
chemical  composition  of  sea-surface  films,  natural slicks,  and
foams.  J. Res. Atmosph. 8: 571-600.

Gucinski, H., D.W. Goupil, and R.E. Baier. 1981. The Sampling and
Composition of the surface microlayer.  in: Atmospheric Pollutants
to Natural Waters. S. Eisenreich, Ed.,  Ann Arbor Press.

Hardy, J.T.   1988.   Anthropogenic  alteration  of the sea-surface.
Guest Editorial. Marine Env. Res. 23:   223-225.

Hardy, J.T.,  E.A.  Crecelius,  L.D.  Antrim, S.L. Kiesser  and V.L.
Broadhurst.  1987.  Aquatic  surface microlayer contamination  in
Chesapeake Bay. Contract  to Maryland Dept.  of  Natural  Resources,
Energy Administration,  Power Plant Research  Program,  Annapolis,
MD. 39 pp.

Hardy, J.T.,  E.A. Crecelius,  C.W.  Apts  and  J.M. Gurtisen.   1988.
Sea-surface contamination in  Puget  Sound:   Part I.  Toxic effects
on fish eggs and larvae.  Marine Env.  Res. 23:   227-249.

Hardy, J.T.,  E.A. Crecelius,  C.W,  Apts  and  J.M. Gurtisen.   1988.
Sea-surface contamination in Puget  Sound:  Part II.  Concentration
and distribution of contaminants.  Marine Env.  Res.  23:  251-271.

Harrick,  N.  J.     1967.     Internal   Reflection  Spectroscopy.
Interscience, New York.

Huhnerfuss, H., P.A.  Lange,  w.  Walter. 1985. Relaxation effects in
monolayers and their contribution to water wave damping.  I.  Wave-
induced phase shifts. J. Colloid Interf. Sci.  108(2):  430-431.

Katsaros, K.B., H. Gucinski, S.S. Atakturk,  R.  Pincus.  Effects of
reduced surface  tension on short waves at  low wind speeds  in  a
fresh water lake, (in press.)

Idppson, A.J. and R.L.  Moran.  1974. Manual  for identification of
early developmental stages of fishes of the Potomac River Estuary.
Maryland Dept. of Natural Resources, Power  Plant  Siting  Program.
PPSP-MP-13. 282 pp.
                               31

-------
Seiburth,  J.  McN.   1983.   Microbiological  and  organic-chemical
processes  in the  surface and mixed layers.  In: P.S. Liss,  W.G.N.
Slinn.  Air-Sea Exchange _of Qas.eg and ,Pa.rticles.   NATO ASI  Series
108, Reidel Publ. Co., Boston.

U.S. Environmental Protection Agency.  1979.  Methods for chemical
analysis of water and wastes.  U.S.  EPA, Washington, DC. EPA 600/4-
79-020.

U.S. Environmental Protection Agency.  1982.  Methods for chemical
analysis of water and wastes.  U.S.  EPA, Washington, DC. EPA 600/4-
79-020.

U.S.  Environmental  Protection  Agency,  Chesapeake  Bay  Program.
1988a.  Review of Technical  Literature  and Characterization  of
Aquatic  Surface  Microlayer  Samples.  Contract  Report  prepared  by
J.T. Hardy, Battelle  Marine Research  Laboratory,  Sequim,  WA, and
Hermann Gucinski, Anne Arundel Community College,  Annapolis, MD.

U.S. Environmental Protection  Agency.  1988b. Method 1624C Revision
B - Volatile Organic  Compounds  by  Isotope Dilution  GC/MS.  Office
of Water Regulations and Standards/Industrial Technology Division
(ITD) Methods. 6/89. Washington, D.C.

U.S. Environmental Protection  Agency.  1988c. Method 1625C Revision
B - Semivolatile  Organic  Compounds  by  Isotope  Dilution  GC/MS.
Office  of  Water   Regulations  and  Standards/Industrial Technology
Division (ITD) Methods. 6/89.  Washington, D.C.

U.S. Environmental Protection Agency.  1988d. Method 1618 Organo-
Halide Pesticides, Organo-Phosphorus Pesticides,  and Phenoxy-Acid
Herbicides by Wide Bore  Capillary  Column Gas Chromatography with
Selective  Detectors. U.S. EPA, Washington, DC.  June  1989.

U.S.  Environmental  Protection  Agency.   1989.  Office  of  Water
Regulations  and   Standards/Industrial  Technology  Division  (ITD)
Methods, Method 1618. 6/89. Washington, D.C.

Unger, M.A., W.G. Maclntyre, J.  Greaves and R.J. Huggett. 1986.  GC
determination of  butyltins  in natural waters by flame photometric
detection   of   hexyl   derivatives    with   mass   spectrometric
confirmation. Chemosphere 15;461-470.

Versar, Inc., July, 1987. Chesapeake Bay Water  Quality Monitoring
Program Meso-Zooplankton Component: August  1984 - December 1986.
Maryland Dept.  of Health  and Mental  Hygiene, Office  of  Ertvir.
Programs,  Baltimore, MD. 21201.

Ward, H.B.  and G.C. Whipple. 1966.  Freshwater Biology.  2nd ed. John
Wiley, New York.  1248 pp.

Zisman, W.A. 1964. Relation of equilibrium contact angle in liquid
and solid  constitution. Advances in Chemistry 43:1.
                               32

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                           APPENDIX A

    FREEMAN  SURFACE MICROLAYER  SAMPLER DESIGN  SPECIFICATIONS

     The microlayer sampler (Figure 3) incorporates the advantages
of previous models in order to provide the Chesapeake Bay Program
with an upgraded,  evaluated collecting device.  The upgrades to the
microlayer sampler include:

     - collection of large sampling volume;
     - high collection efficiency;
     - shallow, nominal, sampling depth;
     - reasonable light weight;
     - ease of repair and disassembly;  and
     - facility of use from small boats.

     Design  specifications for  the microlayer drum  sampler were
submitted for  bid to several contractors.   These  specifications
include:

     The drum material should be metal and thick enough to retain
stiffness.   It  does not  have  to  be  made  of  stainless  steel.
Aluminum is  acceptable  if  the coating extends  over all surfaces.
Tolerance of the drum barrel surface should be within 1/32 inch or
2 mm.   The drum coating should be teflon (polytetrafluoroethylene),
preferably  non-dyed,  with sufficient  thickness  so that  minor
scratches will not expose the metal.  The teflon should be tested
and must provide water contact angles of at least 108 degrees and
critical surface  tension  of 16-18 milli newtons per meter.   The
teflon finish  coat  should be characterized  by infrared spectro-
scopy  and contact angle analysis.   The drum  shaft  should be made
from a non-corrosive material or coated from corrosion.

     The  floats may  consist of  either  foam  floatation with  a
suitable watertight outer  layer or PVC (poly vinyl -chloride) pipe
of  adequate  diameter  to  ensure towing  qualities.    Buoyancy
requirements  must  support the  sampler,   its  attached  sampling
bottles and immerse the drum 2-4 inches during towing operations.
The float  separation must be  sufficient  to minimize  float wake
effects on the drum sampler.

     The supporting  structure may be made of PVC  or  corrosion-
protected metal.  It must  provide  lateral and transverse stability
to withstand waves of up to 3 feet, handling and shipping stress,
and  overboard  launching  and retrieval.    Easy disassembly  and
reassembly is preferred.   The structure must support a wiper and
drain  system  and provide  a secure  platform  for  the  sampling
bottles.  A maximum sampling bottle capacity of 1 U.S.  gallon and
a minimum capacity of 125 milli liters is required.
                              A-l

-------
     An automatic drive is preferred to propel the sampler forward
using the water's motion to turn the drum so that the forward face
of the  drum is  rising and the  after  face is descending.   Drum
rotation  rate  should  be  set  so that  the  drum's  rim tangential
velocity  is  equal to  the  sampler's forward motion via  a paddle
wheel, propeller, or other drive mechanism.  If this set up is not
achievable, then an electric drive that is fear or belt driven is
acceptable.  The electric drive must use a 12 volt DC motor run
from a  standard  12  volt car or  marine lead-acid  battery (i.e.  a
duty cycle with a 24 amp. hour battery) , to  allow for an -adjustable
drum rotation rate consistent with a tangential velocity equal to
a sampler tow speed of 1 to 2,5 knots.

     The wiper and  drain assembly must have  a  flexible blade so
that it maintains contact with the drum at all times.   The use of
teflon coating is preferred to  prevent  sample contamination, but
siliconized rubber may be used with minimum reliability.  The drain
assembly may be made of PVC piping  or an equivalent, but must have
a teflon or silicon coating to prevent sample contamination.

     Freeman Associates, in Berlin, Maryland,  was selected as the
contractor.  Their  design  sketch,  in  Figure  3,  is similar to  a
design developed  by Battelle Marine Science Lab (see Hardy, et al.,
1988) except for these differences:

     - Except for the drum shafts, and pulleys  constructed of T6061
aluminum, construction is almost entirely of PVC with commercially
available grade  pipe  sizes.  Simplicity  and ease of repair and
assembly was emphasized allowing maintenance on-site with a simple
PVC repair kit.

   -  The drive  is unique  in  that  it  synchronizes the drum rotation
rate with the  forward motion of the sampling rig, ensuring the
proper drum advancement  and the fresh  surface layer to be lifted
from the water.   This  drive system avoids  the problems caused by
a fixed speed tow where the tow  speed may exceed or lag behind the
drum rotation rate.

     A higher tow speed in respect to the drum rotation rate will
collapse the surface  film ahead of the  drum,  collecting too much
surface layer in the presence  of a  slick.   Too slow of a tow speed
will  initially   remove   the  surface   film  present,  but  will
subsequently remove subsurface water, causing  a dilution effect in
the  sample  collection.   These  risks  should be minimized by the
chosen design.
                               A-2

-------
              APPENDIX B
JMenidia Jberyllina Toxicity Testing:
Survival, Physical and Chemical Data
Menidia beryl Una. Larval Survival and Growth Test Toxicity Data
Sample Source: Chesapeake Bay
Beginning Date: 5-10-88 Number of
Surviving Organisms/Day
Observation Time:
Exposure
Gulf Breeze
Control

Observation Time;
Exposure
Sea Salt
Control

Observation Time:
Exposure
Choptank
Bulk water

Observation Time :

Exposure
Choptank
Microlayer water


Repl.
A
B
C

Repl.
A
B
C
;
Repl.
A
B
C


Repl.
A
B
C
1033
Day
1
10
10
10
1046
Day
1
10
10
8 of 9
1100
Day
1
10
10
10
1131
Day
1
10
10
10
1414
Day
2
10
10
10
1425
Day
2
10
10
8 of 9
1438
Day
2
10
10
10
1446
Day
2
10
10
10
1045
Day
3
10
10
10
1056
Day
3
10
10
8 of
1109
Day
3
10
10
10
1142
Day
3
10
10
10
1300
Day
4
10
10
10
1304
Day
4
10
10
9 8 of 9
1310
Day
4
10
10
10
1317
Day
4
10
10
10
                B-l

-------
                           APPENDIX B
Menidla Jberyllina Larval Survival and Growth Test Toxicity Data
(continued)
Sample Source:  Chesapeake Bay
Beginning Date:  5-12-88
Observation Time:

Exposure

Gulf Breeze
Control
Repl.

 A
 B
 C
Observation Time:

Exposure           Repl.
Susquehanna
Bulk water
Observation Time:

Exposure

Susquehanna
Microlayer water
Observation Time:

Exposure
       •
Mid-Bay
Bulk water
Observation Time:

Exposure

Mid-Bay
Microlayer water
 A
 B
 C
Repl

 A
 B
 C
Repl

 A
 B
 C
Repl

 A
 B
 C
                          Number of
                   Surviving Organisms/Day
1154
Day
_!
10
10
10
1205
Day
_1
10
10
10
1220
Day
_1
10
10
10
1230
Day
_1
10
10
10
1242
Day
	 1
10
10
10
1418
Day
_2
10
10
10
1428
Day
_2_
10
10
10
1437
Day
_2
10
10
10
1459
Day
_2
10
11
10
1509
Day
	 2
10
10
10
1008
Day
_2.
10
10
10
1018
Day
_3
10
10
10
1028
Day
_3
10
10
10
1038
Day
_3
10
11
10
1058
Day
	 3
10
10
10
0853
Day
_i
10
10
10
0906
Day
_4
10
10
10
0910
Day
_4
10
10
10
0917
Day
4
10
11
10
0923
Day
	 4
10
10
10
                               B-2

-------
                           APPENDIX B
Menidia Jberyllina  Larval  Survival and Growth  Test  Toxicity Data
(continued)
Sample source:  Chesapeake Bay
Beginning Date:  5-14-86
Oba e rvat i on T ime;

Exposure

Gulf Breeze
Control
Repl.

 A
 B
 C
1108
 Day
   I

   6
   6
   6
                          Number of
                   Surviving Organisms/Day
0903
 Day
  _2

  6
  6
  6
1303
 Day
 _3

  6
  6
  6
1441
 Day
 _4

  6
  6
  6
Observation Time:

Exposure

Potomac
Bulk water
Repl

 A
 B
 C
1119
Day
1
0912
Day
2
1300
Day
3
1434
Day
4
6
6
6
6
6
6
5
6
6
5
6
6
Observation Time:

Exposure

Potomac
Microlayer water
Repl

 A
 B
 C
1130
Day
1
0925
Day
2
1258
Day
3
1428
Day
4
6
6
6
6
6
6
6
5
6
6
5
6
                               B-3

-------
                            APPENDIX B

             Initial Test: Exposure Water Quality Data
        (all  temperatures reported are in degrees Celsius)

Sample Source:  Chesapeake Bay
Beginning Date:  5-10-88

                   --Dissolved Oxygen--
Exposure    Day:   £    i    2    3,    4_    p_H    Temp.   Salinity
Gulf Breeze       8.1  7.1  7.2  6.8  7.1   7.7   25.8°      18
Control
Exposure
Sea Salt
Control
      --Dissolved  Oxygen--
Day:  0_     1.    2_     3_   4_    pH   Temp.   Salinity
     8.7   7.2   7.1  6.7   7.0   8.6  23.8°      16
                   --Dissolved Oxygen—
Exposure     Day:  0.    I     2_    3    4_     pH   Temp.   Salinity
Choptank          8.2  7.2  7.2  6.5  6.9    6.8   25.5°      15
Bulk water

                   —Dissolved Oxygen--
Exposure     Day:  £    1.     2_    3.    4_     pH   Temp.   Salinity
Choptank          8.5  7.2  6.6  6.6  6.9    7.8   24.4°      14
Microlayer water
Sample Source:  Chesapeake Bay
Beginning Date:  5-12-88

                   —Dissolved Oxygen--
Exposure     Day:  0.    1.    2_    3_    _4
Gulf Breeze       7.8   7.1  7.0  6.5  7.0
Control
                               pH    Temp.   Salinity
                               7.7   24.1°      15
                   --Dissolved Oxygen--
Exposure     Day:  0.    1.    2    3    4_
Susquehanna       8.6  7.0  6.9  6.5  6.9
Bulk water
                               pH   Temp.
                               8.4   23.0°
Salinity
   15
                   --Dissolved Oxygen—
Exposure     Day:  £    i    2_    3,    4_
Susquehanna       8.8  6.2  6.6  6.7  7.1
Microlayer
                                pjj   Temp.
                                8.4   23.4°
Salinity
   15
                               B-4

-------
                            APPENDIX B

             Initial Test Exposure Water Quality Data (continued)
        (all temperatues reported are in degrees Celsius)

Sample Source:  Chesapeake Bay
Beginning Date:  5-12-88  (continued)

                   --Dissolved Oxygen--
Exposure     Day:  0.    1    2_    3     4    pH   Temp;.   Salinity
Mid-Bay           8.4  6~.1  6.7  6.1  6.9   7.9  24.2°       14
Bulk water

                   —Dissolved Oxygen—
Exposure     Day:  Q    1.    2_    3     4_    pH   Temp.   Salinity
Mid-Bay           8.3  6.8  6.9  6.2  6.9   7.9  24.2°      14
Microlayer
Sample Source:  Chesapeake Bay
Beginning Date:  5-14-88

                   --Dissolved Oxygen--
Exposure     Day:  0.    1.    2    3.    4_
Gulf Breeze       7.8  6.7  7.3  6.4  5.2
Control
                               pJH   Temp.
                               7.6  23.7°
             Salinity
               16
                   --Dissolved Oxygen--
Exposure     Day:  ()    I    2_    3_    4.
Potomac           8.0  4.5  6.8  6.6  5.6
Bulk water
                               pH   Temp.
                               8.2  22.5°
             Salinity
               14
Exposure
Potomac
Microlayer
      --Dissolved Oxygen--
Day:  £    i     2.     3    4
     8.2   4.3   7.0   6.2   5.4
pH   Temp.   Salinity
8.3  22.6°     14
                               B-5

-------
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-------
                           APPENDIX D

       List of Organic Compounds Scanned for in the  Surface
                Microlayer and Bulk Water Samples *

Chemical Name                  pet.ec.tjLon Limits (ug/L)

1,1,1,2-TETRACHLOROETHANE       10
1,1,1-TRICHLOROETHANE           10
1,1,2,2-TETRACHLOROETHANE       10
1,1,2-TRICHLOROETHANE           10
1,1-DICHLOROETHANE              10
1,1-DICHLOROETHENE              10
1,2,3-TRICHLOROBENZENE          10, 12,  OR 20
1,2,3-TRICHLOROPROPANE          10
1,2,3-TRIMETHOXYBENZENE         10, 12,  OR 20
1,2,4,5-TETRACHLOROBENZENE      10, 12,  OR 20
1,2,4-TRICHLOROBENZENE          10, 12,  OR 20
l,2-DIBROMO-3-CHLOROPROPANE     20, 25,  OR 40
1,2-DIBROMOETHANE (EDB)         10
1,2-DICHLOROBENZENE             10, 12,  OR 20
1,2-DICHLOROETHANE              10
1,2-DICHLOROPROPANE             10
1,2-DIPHENYLHYDRAZINE           20, 25,  OR 40
1,2:3,4-DIEPOXYBUTANE           20, 25,  OR 40
1,3,5-TRITHIANE                 50, 62,  OR 100
1,3-BENZENEDIOL (RESORCINOL)     50, 62,  OR 100
l,3-DICHLORO-2-PROPANOL         10, 12,  OR 20
1,3-DICHLOROBENZENE             10, 12,  OR 20
1,3-DICHLOROPROPANE             10
1,4-DICHLOROBENZENE             10, 12,  OR 20
1,4-DINITROBENZENE              20, 25,  OR 40
1,4-NAPHTHOQUINONE              99, 124, OR 198
1,5-NAPHTHALENEDIAMINE          99, 124, OR 198
1-METHYLFLUORENE                10, 12,  OR 20
1-METHYLPHENANTHRENE            10, 12,  OR 20
1-PHENYLNAPHTHALENE             10, 12,  OR 20
2,3,4,6-TETRACHLOROPHENOL       20 OR 25
2,3,6-TRICHLOROPHENOL           10 OR 12
2,3-BENZOFLUORENE               10, 12,  OR 20
2,3-DICHLOROANILINE             10, 12,  OR 20
2,3-DICHLORONITROBENZENE   .     50, 62,  OR 100
2,4,5-TRICHLOROPHENOL           10 OR 12
2,4,5-TRIMETHYLANILINE          20, 25,  OR 40
2,4,6-TRICHLOROPHENOL           10 OR 12
2,4-DIAMINOTOLUENE              99, 124, OR 198
2,4-DICHLOROPHENOL              10 OR 12
2,4-DIMETHYLPHENOL              10, 12,  OR 20
2,4-DINITROPHENOL               50 OR 62
2,4-DINITROTOLUENE              10, 12,  OR 20
2,6-DI-TERT-BUTYL-P-BENZOQINONE 99, 124, OR 198
2,6-DICHLORO-4-NITROANILINE     99, 124, OR 198
2,6-DICHLOROPHENOL              10 OR 12
2,6-DINITROTOLUENE              10, 12,  OR 20
                              D-l

-------
Chemical Name                  De tecti on Li mits (ug/L)
2-(METHYLTHIO)BENZOTHIAZOLE     10, 12, OR 20
2-BROMOCHLOROBENZENE            10, 12, OR 20
2-BUTANONE (MEK)                50
2-CHLORO-l,3-BUTADIENE          10
2-CHLOROETHYLVINYL ETHER        10
2-CHLORONAPHTHALENE             10, 12, OR 20
2-CHLOROPHENOL                  10 OR
2-HEXANONE                      50
2-ISOPROPYLNAPHTHALENE          10, 12, OR 20
2-METHYL-4,6-DINITROPHENOL      20 OR 25
2-METHYLBENZOTHIOAZOLE          10, 12, OR 20
2-METHYLNAPHTHALENE             10, 12, OR 20
2-NITROANILINE                  10, 12, OR 20
2-NITROPHENOL                   20 OR 25
2-PHENYLNAPHTHALENE             10, 12, OR 20
3,3'-DICHLOROBENZlDINE          50, 62, OR 100
3,3'-DIMETHOXYBENZIDINE         50, 62, OR 100
3,5-DIBROMO-4-HYDROXYBENZONITR  50 OR 62
3,6-DIMETHYLPHENANTHRENE        10, 12, OR 20
3-BROMOCHLOROBENZENE            10, 12, OR 20
3-CHLORONITROBENZENE            50, 62, OR 100
3-CHLOROPROPENE                 10
3-METHYLCHOLANTHRENE            10, 12, OR 20
3-NITROAN1LINE                  20, 25, OR 40
4,4'-METHYLENEBIS(2-CHLOROANI)  20, 25, OR 40
4,5-MSTHYLENEPHENANTHRENE       10, 12, OR 20
4-AMINOBIPHENYL                 10, 12, OR 20
4-BROMOPHENYL PHENYL ETHER      10, 12, OR 20
4-CHLORO-2-NITROANILINE         20, 25, OR 40
4-CHLORO-3-KETHYLPHENOL         10 OR 12
4-CHLOROANILINE                 10, 12, OR 20
4-CHLOROPHENYL PHENYL ETHER     10, 12, OR 20
4-METHYL-2-PENTANONE            50
4-NITROANILINE                  50, 62, OR 100
4-NXTROBIPHENYL                 10, 12, OR 20
4-NITROPHENOL                   50 OR 62
5-CHLORO-O-TOLUIDINE            10, 12, OR 20
5-NITRO-O-TOLUIDINE             10, 12, OR 20
7,12-DIMETHYLBENZ(A)ANTHRACENE  10, 12, OR 20
ACENAPHTHENE                    10, 12, OR 20
ACENAPHTHYLENE                  10, 12, OR 20
ACETONE                         50
ACETOPHENONE                    10, 12, OR 20
ACROLEIN                        50
ACRYLONITRILE                   50
ALLYL ALCOHOL                   10
ALPHA-NAPHTHYLAMINE             10, 12, OR 20
ALPHA-PICOLINE                  50, 62, OR 100
ALPHA-TERPINEOL                 10, 12, OR 20
ANILINE                         10, 12, OR 20
ANTHRACENE                      10, 12, OR 20
ARAMITE                         50, 62, OR 100
B-NAPHTHYLAMINE                 50, 62, OR 100
                              D-2

-------
Cheroi cal Name
BENZANTHRONE
BENZENE
BENZENETHIOL
BENZIDINE
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZOJB)FLUORANTHENE
BENZO(GHI)PERYLENE
BSNZO{K)FLUORANTHENE
BENZOIC ACID
BENZYL ALCOHOL
BIPHENYL
BIS (2-CHLOROETHOXY) METHANE
BIS (2-CHLOROISOPROPYL) ETHER
BIS (2-ETHYLHEXYL) PHTHALATE
BIS(2-CHLOROETHYL)ETHER
BROMODICHLOROMETHANE
BROMOFORM
BROMOMETHANE
BUTYL BENZYL PHTHALATE
CARBAZOLE
CARBON DISULFIDE
CARBON TETRACHLORIDE
CHLOROACETONITRILE
CHLOROBENZENE
CHLOROETHANE
CHLOROFORM
CHLOROMETHANE
CHRYSENE
CIS-1,3-DICHLOROPROPENE
CROTONALDEHYDE
CROTOXYPHOS
DI-N-BUTYL PHTHALATE
DI-N-OCTYL PHTHALATE
DIBENZO{A,H)ANTHRACENE
DIBENZOFURAN
DIBENZOTHIOPHENE
DIBROMOCHLOROHETHANE
DIBROMOMETHANE
DIETHYL ETHER
DIETHYL PHTHALATE
DIMETHYL PHTHALATE
DIMETHYL SULFONE
DIPHENYL ETHER
DIPHENYLAMINE
DIPHENYLDISULFIDE
ETHYL CYANIDE
ETHYL METHACRYLATE
ETHYL METHANESULFONATE
ETHYLBENZENE
ETHYLENETHIOUREA
ETHYNYLESTRADIOL 3-METHYL ETHE
FLUORANTHENE
p. g£egfel on Li mi £ s (ug/L)
 50, 62,  OR 100
 10
 10, 12,  OR 20
 50, 62,  OR 100
 10, 12,  OR 20
 10, 12,  OR 20
 10, 12,  OR 20
 20, 25,  OR 40
 10, 12,  OR 20
 50 OR 62
 10 OR 12
 10, 12,  OR 20
 10, 12,  OR 20
 10, 12,  OR 20
 10 OR 12
 10, 12,  OR 20
 10
 10
 50
 10, 12,  OR 20
 20, 25,  OR 40
 10
 10
 10
 10
 50
 10
 50
 10, 12,  OR 20
 10
 50
 99, 124, OR 198
 10
 10, 12,  OR 20
 20, 25,  OR 40
 10, 12,  OR 20
 10, 12,  OR 20
 10
 10
 50
 10, 12,  OR 20
 10, 12,  OR 20
 10, 12,  OR 20
 10, 12,  OR 20
 10, 12,  OR 20
 20, 25,  OR 40
 10
 10
 20, 25,  OR 40
 10
 20, 25,  OR 40
 20, 25,  OR 40
 10, 12,  OR 20
                               D-3

-------
Chemical Name
FLUORENE
HEXACHLORO-1,3-BUTADIENE
HEXACHLOROBENZ ENE
HEXACHLOROCYCLOPENTADIENE
HEXACHLOROETHANE
HEXACHLOROPROPENE
HEXANOIC ACID
INDENO(1,2,3-CD)PYRENE
IODOMETHANE
ISOBUTYL ALCOHOL
ISOPHORONE
ISOSAFROLE
LONGIFOLENE
M-XYLENE
MALACHITE GREEN
METHACRYLONITRILE
METHAPYRILENE
HETHYL METHACRYLATE
METHYL METHANESULFONATE
METHYLENE CHLORIDE
N,N-DIMETHYLFORMAMIDE
N-DECANE (N-C10)
N-DOCOSANE (N-C22)
N-DODECANE (N-C12)
N-EICOSANE (N-C20)
N-HEXACOSANE (N-C26)
N-HEXADECANE (N-C16)
N-NITROSODI-N-BUTYLAMINE
N-NITROSODI-N-PROPYLAMINE
N-NITROSODIETHYLAMINE
N-NITROSODIMETHYLAMINE
N-NITROSODIPHENYLAMINE
N-NITROSOMETHYLETHYLAMINE
N-NITROSOMETHYLPHENYLAMINE
N-NITROSOMORPHOLINE
N-NITROSOPIPERIDINE
N-OCTACOSANE (N-C28)
N-OCTADECANE (N-C18)
N-TETRACOSANE (N-C24)
N-TETRADSCANE (N-C14)
N-TRIACONTANE (N-C30)
NAPHTHALENE
NITROBENZENE
0- + P-XYLENE
0-ANISIDINE
0-CRESOL
O-TOLUIDINE
P-CRESOL
P-CYMSNE
P-DIMETHYLAMINOAZOBENZENE
P-DIOXANE
PENTACHLOROBENZENE
PENTACHLOROETHANE
Detection Limits (ug/L)
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 20, 25, OR 40
 10 OR 12
 20, 25, OR 40
 10
 10
 10, 12, OR 20
 10, 12, OR 20
 50, 62, OR 100
 10
 10, 12, OR 20
 10
 10, 12, OR 20
 10
 20, 25, OR 40
 10
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 20, 25, OR 40
 10, 12, OR 20
 50, 62, OR 100
 20, 25, OR 40
 10, 12, OR 20
 99, 124, OR 198
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10
 10, 12, OR 20
 10, 12, OR 20
 10, 12, OR 20
 10 OR 12
 10, 12, OR 20
 20, 25, OR 40
 10
 20, 25, OR 40
 20, 25, OR 40
                              D-4

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Chemical Name                  Detection Limits (ug/L)
PENTACHLOROPHENOL               50 OR 62
PENTAMETHYLBENZENE              10, 12, OR 20
PERYLENE                        10, 12, OR 20
PHENACETIM                      10, 12, OR 20
PHENANTHRENE         -           10, 12, OR 20
PHENOL                          10, 12, OR 20
PHENOTHIAZINE                   50, 62, OR 100
PRONAMIDE                       10, 12, OR 20
PYRENE                          10, 12, OR 20
PYRIDINE                        10, 12, OR 20
SAFROLE                         10, 12, OR 20
SQUALENE                        99, 124, OR 198
STYRENE                         10, 12, OR 20
T-1,3-DICHLOROPROPENE           10
TETRACHLOROETHENE               10
THIANAPHTHENE                   10, 12, OR 20
THIOACETAMIDE                   20, 25, OR 40
THIOXANTHONE                    20, 25, OR 40
TOLUENE                         10
TRANS-1,2-DICHLOROETHENE        10
TRANS-l,4-DICHLORO-2-BUTENE     50
TRICHLOROETHENE                 10
TRICHLOROFLUOROMETHANE          10
TRIPHENYLENE                    10, 12, OR 20
TRIPROPYLENEGLYCOL METHYL ETHE  99, 124, 198
VINYL ACETATE                   50
VINYL CHLORIDE                  10
*   The  sample  detection  limits  varied  depending  on  the  final
dilution volume of the sample for analyses.
                               D-5

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                          APPENDIX E

         List  of  Pesticides Analyzed for  in  the Surface
              Microlayer and Bulk Water Samples

Chemical Name               Detection  Limits (ug/L)

PHENOXYACID HERBICIDES AND HALOGENATED PESTICIDES:
ALDRIN                        0.025
ALPHA-8HC                     0.025
BETA-BHC                      0.025
DELTA-BHC                     0.025
GAMMA-BHC                     0.063
CAPTAFOL                      0.250
CAPTAN                        0.125
CARBOPHENOTHION               0.500
CHLORDANE                     0.010
CHLOROBENZILATE               0.250
4,4'~DDD                      0.125
4,4'-DDE                      0.125
4,4'-DDT                      0.050
DIALLATE                      0.250
DICHLONE                      0.250
DIELDRIN                      0.025
ENDOSULFAN I                  0.025
ENDOSULFAN II                 0.025
ENDOSULFAN SULFATE            0.125
ENDRIN                        0.025
ENDRIN ALDEHYDE
ENDRIN KETONE                 0.125
HEPTACHLOR                    0.050
HEPTACHLOR EPOXIDE            0.050
ISODRIN                       0.025
KEPONE                        0.250
METHOXYCHLOR                  0.125
MIREX                         0.125
NITROFEN (TOK)                0.125
PCB-1016                      1.0
PCB-1221                      1.0
PCB-1232                      1.0
PCB-1242                      1.0
PCB-1248                      1.0
PCB-1254                      1.0
PCB-1260                      1.0
PCNB     -                     0.050
TOXAPHENE                     1.67
TRIFULRALIN                   0.125
PHENOXY ACID HERBICIDES:
2,4-D                         0.50
DINOSEB                       0.50
2,4,5-T                       0.25
2,4,5-TP                      0.25
                             E-l

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Chemical Name               Detection Limits  (ug/L)

THIOPHOSPHATE PESTICIDES:
AZINPHOS ETHYL                1.0
AZINPHOS METHYL               1.0
CHLORFEVINPHOS                0.5
CHLORPYRIFOS                  0.5
COUMAPHOS                     2.0
CROTOXYPHOS                   1.0
DEMETON .                      1.0
DIAZINON                      0.5
DICHLORVOS                    0.5
DICROTOPHOS                   2.0
DI«ETHOATE                    0.5
DIOXATHION                    4.0
DISULFOTON                    0.5
EPN                           0.5
ETHION                        2.0
FAMPHUR                       0.5
FENSULFOTHION                 1.0
FENTHION                      0.5
LEPTOPHOS                     0.5
KALATHION                     0.5
METHYL PARATHION              0.5
MEVINPHOS                     0.5
MONOCROTOPHOS                 5.0
NALED                         1.0
PARATHION                     1.0
PHORATE                       0.5
PHOSKET                       1.0
PHOSPHAMIDON                  2.0
SULFOTEPP                     0.5
TERBUFOS                      1. 2
TETRACHLORVINPHOS             0.5
TRICHLOROFON                  1.0
TRICHLORONATE                 1.0

TRIAZINE HERBICIDES:
ATRAZINE                      0.8
ALACHLOR                      0.2
CYANAZINE                     0.4
METOLACHLOR                   0.4
SIHAZINE                      0.8
TRIFLURALIN                   0.2
                              E-2

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