Ambient Bioassays - US Environmental Protection Agency

Relationships among exceedences of
metals criteria, the results of ambient
bioassays, and community metrics in
metals-impaired streams
Michael B. Griffith 1 , James M. Lazorchak 2 ,
and Alan T. Herlihy 3
U.S. Environmental Protection Agency, Office of Research
and Development, 1 National Center for Environmental
Assessment & 2 National Exposure Research Laboratory,
Cincinnati, Ohio & 3 Department of Wildlife and Fisheries,
Oregon State University, Corvallis, Oregon

Three Methods
• Chemical criteria – AWQCs or sediment
effect levels – for the protection of aquatic
life
• Ambient Bioassays – assess the
ambient toxicity of water or sediment
• Bioassessments of selected biotic
assemblages – fish or macroinvertebrates

Measurement Endpoints
• Chemical criteria: based on measures of
individual responses in bioassays –
individual-level effects
• Ambient bioassays: measure individual
responses of selected species – individuallevel
effects
• Bioassessments: measure communitylevel
effects

Other Differences
• differences in the stressor specificity:
Chemical criteria - measured contaminants
with criteria
Ambient bioassays - bioavailable toxicants
in the tested media
Community metrics - although sensitive to a
toxicant, may also be sensitive to other
stream alterations

Objectives
• Compare conclusions: effects of
contaminants in different reaches - three
methods for assessment of contaminant
exposure and effects (waters or
sediments)
• Greater understanding of relationships:
levels of biological organization used as
measurement endpoints in these methods

e
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Colorado R.
Upstream Random-selection sites sites
S
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n Juan
R .
R
io
G ra
n d
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Denver
S
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u thPlatteR.
Colorado Springs
Downstream sites
Mineralized region
Arkansas R.

Methods
• Standard EMAP protocols – biological
assemblages, physical habitat, and water
chemistry
• Water – dissolved metals and hardness, 48hr
mortality tests with Ceriodaphna dubia &
Pimephales promelas
• Sediment – total metals, 7-d growth and
mortality tests with Hyallela azteca

Variables to Classify Reaches
Variable
Dissolved concentrations
– Cd, Cu, Pb, or Zn
Survival – C. dubia or P.
promelas (48-hr test)
Sediment concentrations
– Cd, Cu, Pb, or Zn
Survival or growth – H.
azteca (7-day test)
Endpoint
> Hardness-adjusted
dissolved chronic criteria
< 80% survival
> TEL (28-day H. azteca
sediment toxicity test)
< 85% survival or < 90%
growth

Criteria (? = +0.89)
Were sediment
TELs exceeded?
Did sediment
bioassays show
effects?
Comparing Media
No
Yes
Total
Bioassays (? = +0.83)
No
Yes
Total
Were water criteria exceeded?
No
53
15
68
Did water bioassays show
effects?
No
63
10
73
Yes
3
15
18
Yes
4
7
11
Total
56
30
n = 86
Total
67
17
n = 84

Water (? = +0.98)
Did water
bioassays
show effects?
Did sediment
bioassays
show effects
Comparing Methods
No
Yes
Total
Sediment (? = +0.73)
No
Yes
Total
Were water criteria exceeded?
No
65
1
66
Were sediment TELs exceeded?
No
49
5
54
Yes
8
10
18
Yes
18
12
30
Total
73
11
n = 84
Total
67
17
n = 84

Metrics exhibiting differences
Macroinvertebrates
Total taxa richn.
Total abundance
Abundance per taxon
Intolerant taxa richn.
Ephemeroptera taxa richn.
Plecoptera richn.
Trichoptera taxa richn.
EPT taxa richn.
Chironomidae taxa richn.
% Ind., tolerant taxa
Orthoclainae taxa richn.
Tanytanrsini taxa richn.
Coleoptera taxa richn.
% Ind., Ephemeroptera
% Orthocladinae (Chironomidae)
% Tanytarsini (Chironomidae)
% Ind., Coleoptera
% Ind., Diptera & noninsects
% Ind., 5 most common taxa
Collector-filterer taxa richn.
Collector-gatherer taxa richn.
Predator taxa richn.
Shredder taxa richn.
Scraper taxa richn.
Fish
Total species richn.
Salmonidae species richn.
Total abundance
Adult abundance
Salmonidae abundance
% Ind., native species
% Ind., Salmonidae
% Ind., native Salmonidae
% Oncorhynchus (Salmonidae)

Total taxa richness - macroinvertebrates
n =
60
67 18 73 11 55 30 67 17
50
40
30
20
10
0
**
**
**
**
U A U A U A U A
Dissolved
criteria
Water
bioassay
Sediment
TEL
Sediment
bioassay

Total number of individuals - Macroinvertebrates
Collector-gatherer richness
25
20
15
10
5
0
n = 67 18 73 11 55 30 67 17
4000 ns
ns
3000
2000
1000
0
**
U A U A U A U A
Dissolved
criteria
**
*
**
**
U A U A U A U A
Dissolved
criteria
*
Water
bioassay
Water
bioassay
Sediment
TEL
Sediment
TEL
Sediment
bioassay
Sediment
bioassay
EPT taxa richness
Chironomidae taxa richness
n = 67 18 73 11 55 30 67 17
30
25
20
15
10
5
0
30
25
20
15
10
5
0
** **
U A U A U A U A
Dissolved
criteria
Water
bioassay
Sediment
TEL
* *
Sediment
bioassay
ns ns
* **
U A U A U A U A
Dissolved
criteria
Water
bioassay
Sediment
TEL
Sediment
bioassay

Metric
Total taxa richn.- inverts
Total no. individuals
EPT taxa richn.
Total taxa richn.– inverts
Ephemeroptera t. richn.
Chironomidae t. richn.
Individual-effects measures
versus community metrics -
Classified
as
unimpaired
water
Water criteria
67
67
67
73
73
73
Metric <
95% LCL for
unimpaired
group
28
36
20
Water bioassays
29
24
32
Classified
as
impaired
18
18
18
11
11
11
Metric >
95% UCL for
impaired
group
6
1
4
3
2
3

Metric
Total taxa richn.- inverts
Ephemeroptera t. richn.
Shredder taxa richn.
Total taxa richn.– inverts
Tanytarsini t. richn.
Tanytarsini/Chironomidae
Individual-effects measures
versus community metrics –
Classified
as
unimpaired
sediment
Sediment TELs
55
55
55
67
73
73
Metric <
95% LCL for
unimpaired
group
21
25
30
Sediment bioassays
26
24
32
Classified
as
impaired
30
30
30
17
11
11
Metric >
95% UCL for
impaired
group
13
9
8
7
2
3

y = α + α x + β log x + β x log x
0 1 1 0 e 2 1 1 e 2
y = α + β log x
Total taxa richness -
macroinvertebrates
0 0 e 2
60
50
40
30
20
10
0
-3 -2 -1 0 1 2 3 4 5
log e(Sconcentration/chronic AWQC)
(1)
(2)

Total taxa richness -
macroinvertebrates
Intolerant taxa richness
60
50
40
30
20
10
0
20
15
10
5
0
y = 34.22 + 0.02 x 1 - 0.17 log e x 2 - 5.40 * (x 1 log e x 2 )
r 2 = 0.31, F = 266.1 (p < 0.001)
-3 -2 -1 0 1 2 3 4 5
y = 9.40 - 1.48 x 1 + 0.52 log e x 2 - 1.61 * (x 1 log e x 2 )
r 2 = 0.17, F = 127.0 (p < 0.001)
-3 -2 -1 0 1 2 3 4 5
log
e (Σconcentration/chronic AWQC)
Collector-gatherer richness
EPT taxa richness
25
20
15
10
5
0
30
25
20
15
10
5
0
y = 9.12 - 0.07 x 1 - 0.25 log e x 2 - 1.20 (x 1 log e x 2 )
r 2 = 0.18, F = 118.7 (p < 0.001)
-3 -2 -1 0 1 2 3 4 5
y = 16.90 - 2.77 x 1 + 1.57 * log e x 2 - 3.69 * (x 1 log e x 2 )
r 2 = 0.22, F = 153.3 (p < 0.001)
-3 -2 -1 0 1 2 3 4 5
loge (Σconcentration/chronic AWQC)

Total taxa richness -
macroinvertebrates
Intolerant taxa richness
60
50
40
30
20
10
18
16
14
y = 8.95 + 0.35 x
1 - 2.67 * loge x2 + 1.52 (x1 loge x2)
r 2 0
-1 0 1 2 3 4 5
= 0.22, F = 525.0 (p < 0.001)
12
10
8
6
4
2
y = 35.22 + 3.03 x 1 - 5.63 * log e x 2 + 0.97(x 1 log e x 2 )
r 2 = 0.26, F = 243.6 (p < 0.001)
0
-1 0 1 2 3 4 5
log e (Σconcentration/TEL)
Collector-gatherer taxa richness
EPT taxa richness
20
15
10
5
30
y = 14.93 - 0.24 x
1 - 4.86 * log
e x2 + 3.43 * 0
-1 0 1 2 3 4 5
(x
1 loge x2 )
25
20
15
10
5
y = 9.82 + 0.83 x 1 - 2.65 * log e x 2 + 1.32(x 1 log e x 2 )
r 2 = 0.18 F = 118.3 (p < 0.001)
r 2 = 0.21 F = 151.7 (p < 0.001)
0
-1 0 1 2 3 4 5
log e (Σconcentration/TEL)

Conclusion
• Using a simple approach, we demonstrated
effects shown by criteria or
ambient bioassays are both predictive of
community effects as reflected in
community metrics.