Document ID: EPA-HQ-OPP-2003-0024-0023
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-06-03T04:00Z

Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Data
Requirement:
:
EPA
DP
Barcode
D288775
EPA
MRID
458677­
01
EPA
Guideline
70­
1(
Special
Study)

Test
material:
Purity:
n
o
t
reported
Common
name
Atrazine
chemical
name:
IUPAC
CAS
name
6­
chloro­
N­
ethyl­
N'­(
1­
methylethyl)­
1,3,5­
triazine­
2,4­
diamine
CAS
No.
1912­
24­
9
synonyms
EPA
PC
Code:
80803
Primary
Reviewer:
Thomas
M.
Steeger,
Ph.
D.,
Senior
Biologist
Date:
April
9,
2003
Environmental
Fate
and
Effects
Division,
ERB
4,
U.
S.
Environmental
Protection
Agency
Secondary
Reviewer(
s):
Joseph
E.
Tietge,
M.
S.,
Research
Aquatic
Biologist
Date:
Mid­
Continent
Ecology
Division,
National
Health
and
Environmental
Effects
Research
Laboratory
(
Duluth),
U.
S.
Environmental
Protection
Agency
Stephanie
Irene,
Ph.
D.,
Senior
Advisor
Date:
Environmental
Fate
and
Effects
Division,
ERB
3,
U.
S.
Environmental
Protection
Agency
Mary
J.
Frankenberry,
Senior
Statistician
Date:
Environmental
Fate
and
Effects
Division,
ERB
3,
U.
S.
Environmental
Protection
Agency
EPA
PC
Code
080803
Date
Evaluation
Completed:
06/
01/
2003
CITATION:
Smith,
E.,
L
DuPreez
and
K.
Solomon.
2003.
Field
exposure
of
Xenopus
laevis
to
atrazine
and
other
triazines
in
South
Africa:
exposure
characterization
and
assessment
of
laryngeal
and
gonadal
responses.
The
Institute
of
Environmental
&
Human
Health,
Texas
Tech
University,
Lubbock,
Texas
79490
(
USA)
and
School
of
Environmental
Sciences
and
Development,
Potchefstroom
University
for
CHE,
Private
Bag
X6001,
Potchefstroom
2520
(
South
Africa).
Sponsor:
Syngenta
Crop
Protection,
Inc.,
Laboratory
Study
ID
ECORISK
Number
SA­
01B
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
2
of
23
EXECUTIVE
SUMMARY:

This
study
is
the
second
phase
of
a
project
to
assess
the
possible
effects
of
exposure
to
atrazine
and
other
triazines
on
African
clawed
frogs
(
Xenopus
laevis)
in
their
South
African
native
range
under
field
conditions.
The
objective
of
this
phase
of
the
study
was
to
characterize
the
exposure
of
frog
populations
to
atrazine
and
related
triazines
in
surface
waters
of
both
reference
(
no
corn/
no
atrazine­
triazine
use)
and
experimental
(
corn
growing/
atrazine­
triazine
use)
ponds
from
November
2001
through
early
June
2002.
During
the
second
two
months
of
the
study,
rainfall
was
roughly
double
the
10­
year
average
and
resulted
in
all
of
the
earthen
ponds
overflowing
their
banks
for
as
long
as
two
months.
Based
on
EFED's
analysis
of
raw
residue
data,
maximum
atrazine
residues
in
experimental
ponds
over
the
study
period
ranged
from
1.46
to
11.6
ug/
L
while
reference
ponds
ranged
from
0.41
to
1.62
ug/
L.
However,
the
atrazine
degradate
diaminochlorotriazine
(
DACT)
maximum
residues
ranged
from
4.6
to
8.2
ug/
L
at
experimental
sites
and
form
6.8
to
7.4
ug/
L
at
reference
sites.
Two
other
atrazine
degradates,
i.
e.,
desethylated
atrazine
(
DEA)
and
desisopropyl
atrazine
(
DIA)
showed
roughly
similar
maximum
residue
levels
in
both
experimental
and
reference
sites.
Maximum
residues
of
terbuthylazine
ranged
from
1.8
to
5.3
ug/
Lat
experimental
sites
and
from
2.4
to
2.8
ug/
L
at
reference
sites.
According
to
the
report,
triazine
residues
in
the
reference
ponds
were
likely
due
to
wind
effect;
the
authors
speculate
that
the
high
rain
events
during
the
sampling
period
likely
reduced
atrazine
levels
and
that
"
frogs
living
in
these
dams
[
ponds]
were
undoubtedly
exposed
to
much
higher
atrazine
and
other
triazine
levels
than
had
been
recorded
during
the
present
study."
Given
that
atrazine
and/
or
its
degradates
were
present
in
reference
ponds
at
levels
at
times
equivalent
to
some
experimental
pond
sites
and
the
authors
concede
that
atrazine
exposure
prior
to
the
winter
floods
was
likely
higher
at
all
sites,
it
is
unclear
how
the
study
can
differentiate
atrazine
effects
on
frogs
at
reference
and
experimental
sites.
The
high
variability
in
exposure
could
potentially
confound
any
attempt
to
document
significant
differences
in
effects.

The
objective
of
this
study
was
to
examine
the
effects
of
atrazine
on
X.
laevis
in
its
native
habitat
(
South
Africa).
Initially
the
study
was
intended
to
test
whether
morphological
and
biochemical
differences
existed
between
clawed
frogs
in
atrazine­
exposed
(
experimental)
versus
non­
exposed
(
reference)
ponds.
The
criteria
for
differentiating
reference
and
experimental
sites
included
production
of
corn
and
use
of
atrazine
in
the
vicinity,
plus
the
presence
of
X.
laevis
in
a
pond.
Based
on
an
initial
survey
of
the
sampling
area,
five
experimental
(
atrazine
exposure)
and
three
reference
(
no
atrazine
exposure)
sites
were
selected
(
458677­
09).
However,
subsequent
sampling
during
later
phases
of
the
study
revealed
that
the
reference
sites
all
contained
measurable
residues
of
atrazine,
its
degradates,
and
terbutyhylazine
(
triazine
herbicide
not
registered
for
use
in
the
USA)
that
were,
in
some
cases,
higher
than
sites
considered
representative
of
atrazine
exposure
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
3
of
23
I.
MATERIALS
AND
METHODS
GUIDELINE
FOLLOWED:
Nonguideline
Study
COMPLIANCE:
Not
conducted
under
full
GLP;
however,
most
practices
as
defined
by
40
CFR
Part
160,
August
19,
1989
were
established
for
this
study,
including
but
not
limited
to:

°
Written,
authorized
protocol
°
Written,
authorized
Standard
Operating
Procedures
for
all
key
procedures.
°
Organization
and
Personnel
were
sufficient
in
terms
of
number,
education,
training
and
experience.
°
Facilities
were
of
suitable
size
and
construction
°
Equipment
used
was
of
appropriate
design
and
adequate
capacity.
°
Test
material
identity,
strength,
purity
and
composition
were
characterized.
°
Independent
QA
Inspections
were
conducted.
°
Final
report
was
written
°
Raw
data,
documentation,
records,
protocols,
and
final
report
were
archived.

A.
MATERIALS:

1.
Test
Material
Atrazine
Description:
Not
reported
Lot
No./
Batch
No.
:
Not
reported
Purity:
Not
reported
Stability
of
Compound
Under
Test
Conditions:
Not
reported
Storage
conditions
of
test
chemicals:
Not
reported
2.
Test
organism:

Species:
African
clawed
frog
(
Xenopus
laevis)
.
Age
at
test
initiation:
Adults
Weight
at
study
initiation:
(
mean
and
range)
not
reported
Length
at
study
initiation:
(
mean
and
range)
not
reported
Source:
Adult
X.
laevis
were
field
collected
in
two
areas
(
3
non­
corn
growing
areas
and
5
corn
growing
areas)
in
the
vicinity
of
Potchefstrooom,
South
Africa,
using
traps
baited
with
liver
and
meat
scraps.
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
4
of
23
B.
STUDY
DESIGN:

Objective:
1.
To
characterize
the
exposure
of
populations
of
Xenopus
laevis
larvae,
metamorphs
and
adults
to
atrazine
and
related
triazines
in
surface
water
in
reference
(
no
corn
production
or
atrazine/
triazine
use)
and
exposed
habitats
in
the
proximity
of
corn
production
and
atrazine/
triazine
use
in
the
Potchestroom
region
of
South
Africa.

1.
Experimental
Conditions
A
total
of
8
sampling
sites
in
two
adjacent
regions
(
5
in
Viljoenskroon
corn
growing
region
=
E;
3
in
non­
corn
growing
Potchefstroom
region
=
C)
in
South
Africa.
Experimental
site
selection
based
on
proximity
of
corn,
previous
and/
or
planned
use
of
atrazine
and
terbuthylazine,
and
presence
of
Xenopus.
Reference
sites
based
on
absence
of
corn
production,
absence
of
triazine
amd
terbuthylazine
in
the
water,
and
presence
of
Xenopus.

Biweekly
water/
sediment
samples
collected
from
early
November
2001
to
early
June
2002.
Within
5
hours
of
collection
water
samples
kept
at
4oC
and
transported
to
testing
lab
within
24
hours
of
collection.
Water
temperature,
conductivity,
dissolved
oxygen
and
pH
were
recorded
at
reference
points
on
each
sampling
site.

Pesticide
and
metabolite
determinations
in
water
conducted
at
Department
of
Microbiology
of
the
School
of
Environmental
Sciences
and
Development
at
the
Potchefstroom
University.
Quality
control
conducted
at
CSIR
(
Pretoria,
South
Africa)
and
SGS
(
Midrand,
South
Africa).

Climatological
conditions
characterized
in
terms
of
air
temperature
and
rainfall.

Agricultural
practices
in
each
of
the
study
site
catchment
areas
characterized
as
to
crop,
stage
of
crop
development,
e.
g.,
just
planted,
in
flower
etc.,
and
pesticides
applied..

Compounds
of
interest
included
atrazine,
its
metabolites
desethylated
atrazine
(
DEA),
desisopropyl
atrazine
(
DIA),
diaminochlorotriazine
(
DACT),
and
terbuthylazine
plus
simazine
and
acetochlor.

Non­
corn
growing
sites
had
secchi
disc
readings
ranging
from
6.5
to
32
cm;
pH
ranged
from
5.1
to
8.8;
some
of
the
control
ponds
were
subject
to
drying
(
semi­
permanent).

Corn­
growing
sites
had
pond
surface
areas
ranging
from
2,400
m2
to
68,000
m2;
pH
ranged
from
7.2
­
10.8
and
secchi
disc
readings
ranging
from
6.5
to
207
cm.

II.
RESULTS
and
DISCUSSION:
[
All
results
discussed
in
this
section
and
the
next
are
those
reported
by
the
study
authors.
Although
supplemental
data
are
typically
used
in
a
qualitative
manner
only,
EFED
verified
spreadsheet
data
and
ran
basic
statistical
analyses
on
the
major
study
parameters.
See
attached
appendix.
If
results
differed
in
any
substantive
way,
the
difference
was
reported
in
the
text
below.]

Rainfall
during
November
and
December
of
sampling
period
were
more
than
double
(

150
to
200
mm)
the
long
term
average
of
approximately
100
mm
precipitation.
Air
temperature
over
the
study
period
were
relatively
consistent
with
10­
year
minimums
and
maximums.
High
rainfall
in
November
and
December
resulted
in
the
majority
of
the
area
being
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
5
of
23
planted
in
corn
late
in
the
season.
Although
corn
is
typically
planted
in
November,
the
high
rains
delayed
planting
until
the
first
week
of
January.
Because
of
the
heavy
rains,
all
ponds
overflowed
their
embankments
until
early
January.

The
following
insecticides
were
used
in
the
study's
catchment
areas:
terbufos
(
79.2
to
460
g/
ha),
cypermethrin
(
6.6
g/
100
m
row),
monocrotophos
(
1.5
L/
ha).
Herbicides
included
acetochlor,
atrazine,
terbuthylazine,
S­
metolaclhor,
simazine,
cyanazine
and
dimthenomid.

No
herbicides
were
detected
in
any
of
the
sediment
samples
analyzed.
The
level
of
detection
for
water
samples
ranged
from
0.5
to
1.0

g/
L.
The
report
records
values
of
<
0.6

g/
L
as
0.25

g/
L.

Table
1
presents
maximum
residues
of
atrazine
and
its
degradates
DACT,
DEA
and
DIA;
while
maximum
atrazine
residues
were
roughly
an
order
of
magnitude
higher
at
experimental
sites,
reference
sites
had
detectable
residues
of
atrazine.
Maximum
residues
of
DACT,
DEA
and
DIA
were
similar
in
both
reference
and
experimental
sites.
Both
DEA
and
DACT
had
peak
residues
in
reference
ponds
that
were
generally
higher
than
all
of
the
experimental
pond
sites
except
E8.
The
highest
residues
of
DACT
in
reference
ponds
occurred
in
early
December,
early
to
mid­
February
and
mid­
to
late
May;
a
relatively
similar
pattern
occurred
in
experimental
ponds.
Additionally,
terbuthylazine
in
reference
pond
C6
tended
to
remained
relatively
constant
at
around
1

g/
L
until
March
when
it
spiked
to
over
2

g/
L;
only
experimental
ponds
E1,
E6
and
E8
had
monthly
terbuthylazine
residues
higher
than
reference
pond
C6.
While
the
high
rain
events
in
November
and
December
may
have
explained
potential
triazine
contamination
of
reference
sites,
the
spikes
in
February
and
May
suggest
that
triazine
contamination
of
reference
sites
was
recurrent
and
may
not
have
been
associated
with
unusual
weather.
According
to
the
report
though,
triazine
residues
in
the
reference
ponds
were
likely
due
to
wind
effect
and
the
authors
speculate
that
the
high
rain
events
during
the
sampling
period
likely
reduced
atrazine
levels
and
that
"
frogs
living
in
these
dams
were
undoubtedly
exposed
to
much
higher
atrazine
and
other
triazine
levels
than
had
been
recorded
during
the
present
study.

Reference
ponds
contained
soft
water
(
total
hardness
range
18
­
25
mg/
L
as
CaCO3)
while
experimental
ponds
all
contained
moderately
hard
water
(
total
hardness
range:
182
­
200
mg/
L).
Lead
residues
ranged
form
0.08
to
0.09
mg/
L
in
reference
ponds
while
it
was
nondetectable
in
experimental
sites.
Reference
pond
also
seemed
to
be
an
outlier
in
terms
of
the
amount
of
siltation;
while
all
other
ponds
(
reference
and
experimental)
had
silica
levels
ranging
from
4.3
­
8.7
mg/
L,
reference
pond
C6
contained
49.2
mg/
L.
Additionally,
pond
C6
had
the
highest
chromium
(
100.5
mg/
Kg)
and
titanium
(
0.6
mg/
L)
residues
Table
1.
Maximum
residues
of
atrazine,
diaminochlorotriazine
(
DACT),
desethylated
atrazine
(
DEA),
desisopropyl
atrazine
(
DIA),
terbuthylazine,
simazine
and
acetochlor
detected
in
surface
water
collected
from
reference
sites
(
no
corn
grown)
and
experimental
sites
(
corn
grown)
from
November
2001
to
March
2002.

Residue
Reference
Sites
(
C1,
C3,
and
C6)

g/
L
Experimental
Sites
(
E1,
E3,
E4,
E6,
and
E8)

g/
L
Atrazine
0.41
­
1.62
1.46
­
11.6
DACT
6.83
­
7.38
4.59
­
8.16
DEA
0.38
­
2.21
0.57
­
1.9
DIA
0.45
­
1.34
0.69
­
0.93
Terbuthylazine
2.39
­
2.79
1.82
­
5.30
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
6
of
23
Simizine
0.25
­
0.25
0.25
­
3.10
Acetochlor
0.25
­
0.25
0.25
­
1.0
E.
STUDY
DEFICIENCIES:

Atrazine,
its
degradates
and
terbuthylazine
are
present
in
reference
sites.
Study
failed
to
provide
data
on
other
pesticides.

F.
REVIEWER'S
COMMENTS:

This
study
is
the
second
phase
of
a
project
to
assess
the
possible
effects
of
exposure
to
atrazine
and
other
triazines
on
African
clawed
frogs
(
Xenopus
laevis)
in
their
South
African
native
range
under
field
conditions.
The
objective
of
this
phase
of
the
study
was
to
characterize
the
exposure
of
frog
populations
to
atrazine
and
related
triazines
in
surface
waters
of
both
reference
(
no
corn/
no
atrazine­
triazine
use)
and
experimental
(
corn
growing/
atrazine­
triazine
use)
ponds
from
November
2001
through
early
June
2002.
During
the
second
two
months
of
the
study,
rainfall
was
roughly
double
the
10­
year
average
and
resulted
in
all
of
the
earthen
ponds
overflowing
their
banks
for
as
long
as
two
months.
Based
on
EFED's
analysis
of
raw
residue
data,
maximum
atrazine
residues
in
experimental
ponds
over
the
study
period
ranged
from
1.46
to
11.6
ug/
L
while
reference
ponds
ranged
from
0.41
to
1.62
ug/
L.
However,
the
atrazine
degradate
diaminochlorotriazine
(
DACT)
maximum
residues
ranged
from
4.6
to
8.2
ug/
L
at
experimental
sites
and
form
6.8
to
7.4
ug/
L
at
reference
sites.
Two
other
atrazine
degradates,
i.
e.,
desethylated
atrazine
(
DEA)
and
desisopropyl
atrazine
(
DIA)
showed
roughly
similar
maximum
residue
levels
in
both
experimental
and
reference
sites.
Maximum
residues
of
terbuthylazine
ranged
from
1.8
to
5.3
ug/
Lat
experimental
sites
and
from
2.4
to
2.8
ug/
L
at
reference
sites.
According
to
the
report,
triazine
residues
in
the
reference
ponds
were
likely
due
to
wind
effect;
the
authors
speculate
that
the
high
rain
events
during
the
sampling
period
likely
reduced
atrazine
levels
and
that
"
frogs
living
in
these
dams
[
ponds]
were
undoubtedly
exposed
to
much
higher
atrazine
and
other
triazine
levels
than
had
been
recorded
during
the
present
study."
Given
that
atrazine
and/
or
its
degradates
were
present
in
reference
ponds
at
levels
at
times
equivalent
to
some
experimental
pond
sites
and
the
authors
concede
that
atrazine
exposure
prior
to
the
winter
floods
was
likely
higher
at
all
sites,
it
is
unclear
how
the
study
can
differentiate
atrazine
effects
on
frogs
at
reference
and
experimental
sites.
The
high
variability
in
exposure
could
potentially
confound
any
attempt
to
document
significant
differences
in
effects.

G.
CONCLUSIONS:

This
study
is
the
second
phase
of
a
project
to
assess
the
possible
effects
of
exposure
to
atrazine
and
other
triazines
on
African
clawed
frogs
(
Xenopus
laevis)
in
their
South
African
native
range
under
field
conditions.
The
objective
of
this
phase
of
the
study
was
to
characterize
the
exposure
of
frog
populations
to
atrazine
and
related
triazines
in
surface
waters
of
both
reference
(
no
corn/
no
atrazine­
triazine
use)
and
experimental
(
corn
growing/
atrazine­
triazine
use)
ponds
from
November
2001
through
early
June
2002.
During
the
second
two
months
of
the
study,
rainfall
was
roughly
double
the
10­
year
average
and
resulted
in
all
of
the
earthen
ponds
overflowing
their
banks
for
as
long
as
two
months.
Based
on
EFED's
analysis
of
raw
residue
data,
maximum
atrazine
residues
in
experimental
ponds
over
the
study
period
ranged
from
1.46
to
11.6
ug/
L
while
reference
ponds
ranged
from
0.41
to
1.62
ug/
L.
However,
the
atrazine
degradate
diaminochlorotriazine
(
DACT)
maximum
residues
ranged
from
4.6
to
8.2
ug/
L
at
experimental
sites
and
form
6.8
to
7.4
ug/
L
at
reference
sites.
Two
other
atrazine
degradates,
i.
e.,
desethylated
atrazine
(
DEA)
and
desisopropyl
atrazine
(
DIA)
showed
roughly
similar
maximum
residue
levels
in
both
experimental
and
reference
sites.
Maximum
residues
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
7
of
23
of
terbuthylazine
ranged
from
1.8
to
5.3
ug/
Lat
experimental
sites
and
from
2.4
to
2.8
ug/
L
at
reference
sites.
According
to
the
report,
triazine
residues
in
the
reference
ponds
were
likely
due
to
wind
effect;
the
authors
speculate
that
the
high
rain
events
during
the
sampling
period
likely
reduced
atrazine
levels
and
that
"
frogs
living
in
these
dams
[
ponds]
were
undoubtedly
exposed
to
much
higher
atrazine
and
other
triazine
levels
than
had
been
recorded
during
the
present
study."
Given
that
atrazine
and/
or
its
degradates
were
present
in
reference
ponds
at
levels
at
times
equivalent
to
some
experimental
pond
sites
and
the
authors
concede
that
atrazine
exposure
prior
to
the
winter
floods
was
likely
higher
at
all
sites,
it
is
unclear
how
the
study
can
differentiate
atrazine
effects
on
frogs
at
reference
and
experimental
sites.
The
high
variability
in
exposure
could
potentially
confound
any
attempt
to
document
significant
differences
in
effects.
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
8
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
51
Obs
SITE
RESIDUE
TREAT
_
TYPE_
_
FREQ_
MEAN
STD
MIN
MAX
1
E1
ATRA
CORN
GROW
0
24
3.07583
1.82021
0.05
6.78
2
E1
DACT
CORN
GROW
0
24
0.94542
1.64876
0.05
5.20
3
E1
DEA
CORN
GROW
0
24
0.68417
0.46684
0.05
1.66
4
E1
DIA
CORN
GROW
0
24
0.39042
0.24017
0.05
0.93
5
E1
TERB
CORN
GROW
0
24
2.84875
1.46945
0.05
5.30
6
E3
ATRA
CORN
GROW
0
24
0.79667
0.32979
0.14
1.46
7
E3
DACT
CORN
GROW
0
24
1.07333
1.81710
0.05
5.96
8
E3
DEA
CORN
GROW
0
24
0.30375
0.16691
0.05
0.64
9
E3
DIA
CORN
GROW
0
24
0.25375
0.19147
0.05
0.81
10
E3
TERB
CORN
GROW
0
24
0.87667
0.79778
0.05
3.31
11
E4
ATRA
CORN
GROW
0
24
0.56333
0.43697
0.15
1.96
12
E4
DACT
CORN
GROW
0
24
1.04875
1.51311
0.05
4.59
13
E4
DEA
CORN
GROW
0
24
0.19333
0.11698
0.05
0.57
14
E4
DIA
CORN
GROW
0
24
0.23333
0.18647
0.05
0.69
15
E4
TERB
CORN
GROW
0
24
0.56250
0.60623
0.05
1.82
16
E6
ATRA
CORN
GROW
0
24
2.19500
1.39259
0.05
4.46
17
E6
DACT
CORN
GROW
0
24
1.46625
2.01606
0.05
6.40
18
E6
DEA
CORN
GROW
0
24
0.51542
0.46881
0.05
1.90
19
E6
DIA
CORN
GROW
0
24
0.27875
0.22601
0.05
0.86
20
E6
TERB
CORN
GROW
0
24
1.77917
1.17789
0.05
4.43
21
E8
ATRA
CORN
GROW
0
24
3.33875
2.58250
0.05
11.60
22
E8
DACT
CORN
GROW
0
24
1.40375
2.34236
0.05
8.16
23
E8
DEA
CORN
GROW
0
24
0.45875
0.37055
0.05
1.25
24
E8
DIA
CORN
GROW
0
24
0.40208
0.23805
0.05
0.88
25
E8
TERB
CORN
GROW
0
24
1.61542
1.12659
0.05
3.48
26
R1
ATRA
REFERENCE
0
24
0.24542
0.10496
0.05
0.41
27
R1
DACT
REFERENCE
0
24
1.01792
1.67744
0.05
6.88
28
R1
DEA
REFERENCE
0
24
0.12958
0.12743
0.05
0.60
29
R1
DIA
REFERENCE
0
24
0.19958
0.11845
0.05
0.47
30
R1
TERB
REFERENCE
0
24
0.32333
0.64632
0.05
2.11
31
R3
ATRA
REFERENCE
0
24
0.18042
0.15502
0.05
0.57
32
R3
DACT
REFERENCE
0
24
1.39167
1.90289
0.05
7.38
33
R3
DEA
REFERENCE
0
24
0.26333
0.56395
0.05
2.21
34
R3
DIA
REFERENCE
0
24
0.24000
0.27233
0.05
1.34
35
R3
TERB
REFERENCE
0
24
0.55708
0.88616
0.05
2.79
36
R6
ATRA
REFERENCE
0
24
0.24083
0.16981
0.05
0.69
37
R6
DACT
REFERENCE
0
24
1.17708
1.69010
0.05
6.82
38
R6
DEA
REFERENCE
0
24
0.10000
0.08038
0.05
0.38
39
R6
DIA
REFERENCE
0
24
0.16542
0.09385
0.05
0.45
40
R6
TERB
REFERENCE
0
24
1.08042
0.50886
0.48
2.67
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
9
of
23
AVERAGE
CHEMICAL
RESIDUES
IN
CORN­
GROWING
AND
REFERENCE
SITES
IN
SOUTH
AFRICA
52
Obs
TREAT
RESIDUE
_
TYPE_
_
FREQ_
MEAN
STD
MIN
MAX
1
CORN
GROW
ATRA
0
5
1.99392
1.27471
0.56333
3.33875
2
CORN
GROW
DACT
0
5
1.18750
0.23203
0.94542
1.46625
3
CORN
GROW
DEA
0
5
0.43108
0.19018
0.19333
0.68417
4
CORN
GROW
DIA
0
5
0.31167
0.07898
0.23333
0.40208
5
CORN
GROW
TERB
0
5
1.53650
0.89039
0.56250
2.84875
6
REFERENCE
ATRA
0
3
0.22222
0.03628
0.18042
0.24542
7
REFERENCE
DACT
0
3
1.19556
0.18756
1.01792
1.39167
8
REFERENCE
DEA
0
3
0.16431
0.08703
0.10000
0.26333
9
REFERENCE
DIA
0
3
0.20167
0.03734
0.16542
0.24000
10
REFERENCE
TERB
0
3
0.65361
0.38766
0.32333
1.08042
NONPARAMETRIC
COMPARISON
OF
CHEMICAL
RESIDUES
ACROSS
SAMPLING
SITES
53
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
ATRA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
NPAR1WAY
Procedure
Wilcoxon
Scores
(
Rank
Sums)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
3463.00
2316.0
254.513858
144.291667
E3
24
2665.00
2316.0
254.513858
111.041667
E4
24
2085.00
2316.0
254.513858
86.875000
E6
24
3345.00
2316.0
254.513858
139.375000
E8
24
3504.00
2316.0
254.513858
146.000000
R1
24
1313.50
2316.0
254.513858
54.729167
R3
24
934.00
2316.0
254.513858
38.916667
R6
24
1218.50
2316.0
254.513858
50.770833
Average
scores
were
used
for
ties.

Kruskal­
Wallis
Test
Chi­
Square
109.1485
DF
7
Pr
>
Chi­
Square
<.
0001
Median
Scores
(
Number
of
Points
Above
Median)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
21.0
12.0
2.297278
0.875000
E3
24
19.0
12.0
2.297278
0.791667
E4
24
9.0
12.0
2.297278
0.375000
E6
24
22.0
12.0
2.297278
0.916667
E8
24
21.0
12.0
2.297278
0.875000
R1
24
0.0
12.0
2.297278
0.000000
R3
24
1.0
12.0
2.297278
0.041667
R6
24
3.0
12.0
2.297278
0.125000
Average
scores
were
used
for
ties.

Median
One­
Way
Analysis
Chi­
Square
110.4219
DF
7
Pr
>
Chi­
Square
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
10
of
23
NONPARAMETRIC
COMPARISON
OF
CHEMICAL
RESIDUES
ACROSS
SAMPLING
SITES
55
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DACT
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
NPAR1WAY
Procedure
Wilcoxon
Scores
(
Rank
Sums)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
2130.00
2316.0
243.756869
88.75000
E3
24
2220.00
2316.0
243.756869
92.50000
E4
24
2202.00
2316.0
243.756869
91.75000
E6
24
2449.50
2316.0
243.756869
102.06250
E8
24
2430.00
2316.0
243.756869
101.25000
R1
24
2238.00
2316.0
243.756869
93.25000
R3
24
2473.50
2316.0
243.756869
103.06250
R6
24
2385.00
2316.0
243.756869
99.37500
Average
scores
were
used
for
ties.

Kruskal­
Wallis
Test
Chi­
Square
1.8154
DF
7
Pr
>
Chi­
Square
0.9693
Median
Scores
(
Number
of
Points
Above
Median)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
11.0
12.0
2.297278
0.458333
E3
24
11.0
12.0
2.297278
0.458333
E4
24
12.0
12.0
2.297278
0.500000
E6
24
12.0
12.0
2.297278
0.500000
E8
24
14.0
12.0
2.297278
0.583333
R1
24
11.0
12.0
2.297278
0.458333
R3
24
13.0
12.0
2.297278
0.541667
R6
24
12.0
12.0
2.297278
0.500000
Average
scores
were
used
for
ties.

Median
One­
Way
Analysis
Chi­
Square
1.3264
DF
7
Pr
>
Chi­
Square
0.9877
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
11
of
23
NONPARAMETRIC
COMPARISON
OF
CHEMICAL
RESIDUES
ACROSS
SAMPLING
SITES
57
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DEA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
NPAR1WAY
Procedure
Wilcoxon
Scores
(
Rank
Sums)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
3596.50
2316.0
251.896139
149.854167
E3
24
2741.00
2316.0
251.896139
114.208333
E4
24
2145.00
2316.0
251.896139
89.375000
E6
24
2974.00
2316.0
251.896139
123.916667
E8
24
2979.00
2316.0
251.896139
124.125000
R1
24
1435.50
2316.0
251.896139
59.812500
R3
24
1449.00
2316.0
251.896139
60.375000
R6
24
1208.00
2316.0
251.896139
50.333333
Average
scores
were
used
for
ties.

Kruskal­
Wallis
Test
Chi­
Square
75.5240
DF
7
Pr
>
Chi­
Square
<.
0001
Median
Scores
(
Number
of
Points
Above
Median)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
23.000000
12.0
2.277249
0.958333
E3
24
17.166667
12.0
2.277249
0.715278
E4
24
11.166667
12.0
2.277249
0.465278
E6
24
17.166667
12.0
2.277249
0.715278
E8
24
17.166667
12.0
2.277249
0.715278
R1
24
4.333333
12.0
2.277249
0.180556
R3
24
3.000000
12.0
2.277249
0.125000
R6
24
3.000000
12.0
2.277249
0.125000
Average
scores
were
used
for
ties.

Median
One­
Way
Analysis
Chi­
Square
71.2969
DF
7
Pr
>
Chi­
Square
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
12
of
23
NONPARAMETRIC
COMPARISON
OF
CHEMICAL
RESIDUES
ACROSS
SAMPLING
SITES
59
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DIA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
NPAR1WAY
Procedure
Wilcoxon
Scores
(
Rank
Sums)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
3075.50
2316.0
254.029783
128.145833
E3
24
2274.50
2316.0
254.029783
94.770833
E4
24
2097.50
2316.0
254.029783
87.395833
E6
24
2326.50
2316.0
254.029783
96.937500
E8
24
3114.50
2316.0
254.029783
129.770833
R1
24
1983.00
2316.0
254.029783
82.625000
R3
24
1967.00
2316.0
254.029783
81.958333
R6
24
1689.50
2316.0
254.029783
70.395833
Average
scores
were
used
for
ties.

Kruskal­
Wallis
Test
Chi­
Square
25.6164
DF
7
Pr
>
Chi­
Square
0.0006
The
NPAR1WAY
Procedure
Median
Scores
(
Number
of
Points
Above
Median)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
18.00
12.0
2.261098
0.750000
E3
24
11.50
12.0
2.261098
0.479167
E4
24
10.50
12.0
2.261098
0.437500
E6
24
11.50
12.0
2.261098
0.479167
E8
24
18.00
12.0
2.261098
0.750000
R1
24
10.50
12.0
2.261098
0.437500
R3
24
9.50
12.0
2.261098
0.395833
R6
24
6.50
12.0
2.261098
0.270833
Average
scores
were
used
for
ties.

Median
One­
Way
Analysis
Chi­
Square
19.4252
DF
7
Pr
>
Chi­
Square
0.0070
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
13
of
23
NONPARAMETRIC
COMPARISON
OF
CHEMICAL
RESIDUES
ACROSS
SAMPLING
SITES
61
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
TERB
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
NPAR1WAY
Procedure
Wilcoxon
Scores
(
Rank
Sums)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
3715.50
2316.0
252.107852
154.812500
E3
24
2158.50
2316.0
252.107852
89.937500
E4
24
1664.00
2316.0
252.107852
69.333333
E6
24
3049.50
2316.0
252.107852
127.062500
E8
24
2890.50
2316.0
252.107852
120.437500
R1
24
1112.00
2316.0
252.107852
46.333333
R3
24
1395.50
2316.0
252.107852
58.145833
R6
24
2542.50
2316.0
252.107852
105.937500
Average
scores
were
used
for
ties.

Kruskal­
Wallis
Test
Chi­
Square
77.4362
DF
7
Pr
>
Chi­
Square
<.
0001
Median
Scores
(
Number
of
Points
Above
Median)
for
Variable
UG
Classified
by
Variable
SITE
Sum
of
Expected
Std
Dev
Mean
SITE
N
Scores
Under
H0
Under
H0
Score
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ
E1
24
21.0
12.0
2.297278
0.875000
E3
24
11.0
12.0
2.297278
0.458333
E4
24
7.0
12.0
2.297278
0.291667
E6
24
18.0
12.0
2.297278
0.750000
E8
24
16.0
12.0
2.297278
0.666667
R1
24
3.0
12.0
2.297278
0.125000
R3
24
6.0
12.0
2.297278
0.250000
R6
24
14.0
12.0
2.297278
0.583333
Average
scores
were
used
for
ties.

Median
One­
Way
Analysis
Chi­
Square
46.4236
DF
7
Pr
>
Chi­
Square
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
14
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
63
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
ATRA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Class
Level
Information
Class
Levels
Values
SITE
8
E1
E3
E4
E6
E8
R1
R3
R6
Number
of
observations
192
Dependent
Variable:
UG
Sum
of
Source
DF
Squares
Mean
Square
F
Value
Pr
>
F
Model
7
297.3024703
42.4717815
27.66
<.
0001
Error
184
282.5627875
1.5356673
Corrected
Total
191
579.8652578
R­
Square
Coeff
Var
Root
MSE
UG
Mean
0.512710
93.20732
1.239220
1.329531
Source
DF
Anova
SS
Mean
Square
F
Value
Pr
>
F
SITE
7
297.3024703
42.4717815
27.66
<.
0001
Levene's
Test
for
Homogeneity
of
UG
Variance
ANOVA
of
Squared
Deviations
from
Group
Means
Sum
of
Mean
Source
DF
Squares
Square
F
Value
Pr
>
F
SITE
7
890.5
127.2
4.85
<.
0001
Error
184
4830.0
26.2501
Bartlett's
Test
for
Homogeneity
of
UG
Variance
Source
DF
Chi­
Square
Pr
>
ChiSq
SITE
7
347.0
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
15
of
23
Bonferroni
(
Dunn)
t
Tests
for
UG
NOTE:
This
test
controls
the
Type
I
experimentwise
error
rate,
but
it
generally
has
a
higher
Type
II
error
rate
than
REGWQ.

Alpha
0.05
Error
Degrees
of
Freedom
184
Error
Mean
Square
1.535667
Critical
Value
of
t
3.17001
Minimum
Significant
Difference
1.134
Means
with
the
same
letter
are
not
significantly
different.

Bon
Grouping
Mean
N
SITE
A
3.3388
24
E8
A
B
A
3.0758
24
E1
B
B
2.1950
24
E6
C
0.7967
24
E3
C
C
0.5633
24
E4
C
C
0.2454
24
R1
C
C
0.2408
24
R6
C
C
0.1804
24
R3
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
16
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
67
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DACT
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Class
Level
Information
Class
Levels
Values
SITE
8
E1
E3
E4
E6
E8
R1
R3
R6
Number
of
observations
192
Dependent
Variable:
UG
Sum
of
Source
DF
Squares
Mean
Square
F
Value
Pr
>
F
Model
7
6.8600062
0.9800009
0.29
0.9577
Error
184
624.5005417
3.3940247
Corrected
Total
191
631.3605479
R­
Square
Coeff
Var
Root
MSE
UG
Mean
0.010865
154.7464
1.842288
1.190521
Source
DF
Anova
SS
Mean
Square
F
Value
Pr
>
F
SITE
7
6.86000625
0.98000089
0.29
0.9577
Levene's
Test
for
Homogeneity
of
UG
Variance
ANOVA
of
Squared
Deviations
from
Group
Means
Sum
of
Mean
Source
DF
Squares
Square
F
Value
Pr
>
F
SITE
7
158.5
22.6424
0.45
0.8688
Error
184
9242.4
50.2302
Bartlett's
Test
for
Homogeneity
of
UG
Variance
Source
DF
Chi­
Square
Pr
>
ChiSq
SITE
7
6.2865
0.5067
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
17
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
70
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DACT
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Bonferroni
(
Dunn)
t
Tests
for
UG
NOTE:
This
test
controls
the
Type
I
experimentwise
error
rate,
but
it
generally
has
a
higher
Type
II
error
rate
than
REGWQ.

Alpha
0.05
Error
Degrees
of
Freedom
184
Error
Mean
Square
3.394025
Critical
Value
of
t
3.17001
Minimum
Significant
Difference
1.6859
Means
with
the
same
letter
are
not
significantly
different.

Bon
Grouping
Mean
N
SITE
A
1.4663
24
E6
A
A
1.4038
24
E8
A
A
1.3917
24
R3
A
A
1.1771
24
R6
A
A
1.0733
24
E3
A
A
1.0488
24
E4
A
A
1.0179
24
R1
A
A
0.9454
24
E1
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
18
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
71
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DEA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Class
Level
Information
Class
Levels
Values
SITE
8
E1
E3
E4
E6
E8
R1
R3
R6
Number
of
observations
192
Dependent
Variable:
UG
Sum
of
Source
DF
Squares
Mean
Square
F
Value
Pr
>
F
Model
7
7.03822500
1.00546071
8.40
<.
0001
Error
184
22.01816667
0.11966395
Corrected
Total
191
29.05639167
R­
Square
Coeff
Var
Root
MSE
UG
Mean
0.242226
104.4958
0.345925
0.331042
Source
DF
Anova
SS
Mean
Square
F
Value
Pr
>
F
SITE
7
7.03822500
1.00546071
8.40
<.
0001
Levene's
Test
for
Homogeneity
of
UG
Variance
ANOVA
of
Squared
Deviations
from
Group
Means
Sum
of
Mean
Source
DF
Squares
Square
F
Value
Pr
>
F
SITE
7
2.2597
0.3228
2.39
0.0233
Error
184
24.8825
0.1352
Bartlett's
Test
for
Homogeneity
of
UG
Variance
Source
DF
Chi­
Square
Pr
>
ChiSq
SITE
7
140.8
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
19
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
74
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DEA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Bonferroni
(
Dunn)
t
Tests
for
UG
NOTE:
This
test
controls
the
Type
I
experimentwise
error
rate,
but
it
generally
has
a
higher
Type
II
error
rate
than
REGWQ.

Alpha
0.05
Error
Degrees
of
Freedom
184
Error
Mean
Square
0.119664
Critical
Value
of
t
3.17001
Minimum
Significant
Difference
0.3166
Means
with
the
same
letter
are
not
significantly
different.

Bon
Grouping
Mean
N
SITE
A
0.68417
24
E1
A
B
A
0.51542
24
E6
B
A
B
A
C
0.45875
24
E8
B
C
B
D
C
0.30375
24
E3
B
D
C
B
D
C
0.26333
24
R3
D
C
D
C
0.19333
24
E4
D
D
0.12958
24
R1
D
D
0.10000
24
R6
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
20
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
75
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DIA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Class
Level
Information
Class
Levels
Values
SITE
8
E1
E3
E4
E6
E8
R1
R3
R6
Number
of
observations
192
Dependent
Variable:
UG
Sum
of
Source
DF
Squares
Mean
Square
F
Value
Pr
>
F
Model
7
1.21022500
0.17288929
4.14
0.0003
Error
184
7.67894167
0.04173338
Corrected
Total
191
8.88916667
R­
Square
Coeff
Var
Root
MSE
UG
Mean
0.136146
75.54545
0.204287
0.270417
Source
DF
Anova
SS
Mean
Square
F
Value
Pr
>
F
SITE
7
1.21022500
0.17288929
4.14
0.0003
Levene's
Test
for
Homogeneity
of
UG
Variance
ANOVA
of
Squared
Deviations
from
Group
Means
Sum
of
Mean
Source
DF
Squares
Square
F
Value
Pr
>
F
SITE
7
0.0781
0.0112
1.07
0.3813
Error
184
1.9095
0.0104
Bartlett's
Test
for
Homogeneity
of
UG
Variance
Source
DF
Chi­
Square
Pr
>
ChiSq
SITE
7
35.1037
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
21
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
78
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
DIA
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Bonferroni
(
Dunn)
t
Tests
for
UG
NOTE:
This
test
controls
the
Type
I
experimentwise
error
rate,
but
it
generally
has
a
higher
Type
II
error
rate
than
REGWQ.

Alpha
0.05
Error
Degrees
of
Freedom
184
Error
Mean
Square
0.041733
Critical
Value
of
t
3.17001
Minimum
Significant
Difference
0.1869
Means
with
the
same
letter
are
not
significantly
different.

Bon
Grouping
Mean
N
SITE
A
0.40208
24
E8
A
A
0.39042
24
E1
A
B
A
0.27875
24
E6
B
A
B
A
0.25375
24
E3
B
A
B
A
0.24000
24
R3
B
A
B
A
0.23333
24
E4
B
B
0.19958
24
R1
B
B
0.16542
24
R6
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
22
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
79
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
TERB
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Class
Level
Information
Class
Levels
Values
SITE
8
E1
E3
E4
E6
E8
R1
R3
R6
Number
of
observations
192
Dependent
Variable:
UG
Sum
of
Source
DF
Squares
Mean
Square
F
Value
Pr
>
F
Model
7
118.3988167
16.9141167
18.58
<.
0001
Error
184
167.4817500
0.9102269
Corrected
Total
191
285.8805667
R­
Square
Coeff
Var
Root
MSE
UG
Mean
0.414155
79.14758
0.954058
1.205417
Source
DF
Anova
SS
Mean
Square
F
Value
Pr
>
F
SITE
7
118.3988167
16.9141167
18.58
<.
0001
Levene's
Test
for
Homogeneity
of
UG
Variance
ANOVA
of
Squared
Deviations
from
Group
Means
Sum
of
Mean
Source
DF
Squares
Square
F
Value
Pr
>
F
SITE
7
65.4317
9.3474
5.16
<.
0001
Error
184
333.2
1.8111
Bartlett's
Test
for
Homogeneity
of
UG
Variance
Source
DF
Chi­
Square
Pr
>
ChiSq
SITE
7
41.4268
<.
0001
Data
Evaluation
Report
on
Field
Exposure
of
Xenopus
laevis
to
Atrazine
and
Other
Triazines
in
South
Africa:
Exposure
Characterization
and
Assessment
of
Laryngeal
and
Gonadal
Responses
EPA
MRID
Number
458677­
01
Page
23
of
23
ANOVA
FOR
CHEMICAL
RESIDUES
ACROSS
SAMPLING
AREAS
82
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RESIDUE=
TERB
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

The
ANOVA
Procedure
Bonferroni
(
Dunn)
t
Tests
for
UG
NOTE:
This
test
controls
the
Type
I
experimentwise
error
rate,
but
it
generally
has
a
higher
Type
II
error
rate
than
REGWQ.

Alpha
0.05
Error
Degrees
of
Freedom
184
Error
Mean
Square
0.910227
Critical
Value
of
t
3.17001
Minimum
Significant
Difference
0.8731
Means
with
the
same
letter
are
not
significantly
different.

Bon
Grouping
Mean
N
SITE
A
2.8488
24
E1
B
1.7792
24
E6
B
C
B
1.6154
24
E8
C
B
C
B
D
1.0804
24
R6
C
D
C
D
0.8767
24
E3
D
D
0.5625
24
E4
D
D
0.5571
24
R3
D
D
0.3233
24
R1