In cooperation with the United States Department of Agriculture Forest Service, Missoula
Technology and Development Center
Toxicity of Wildland Fire Foams to Invasive Aquatic
Species
By Edward E. Little and Holly Puglis
U.S. Department of the Interior
U.S. Geological Survey
Final Report October 10, 2014
1
U.S. Department of the Interior
U.S. Geological Survey
U.S. Geological Survey, Reston, Virginia
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2
Contents
Introduction .................................................................................................................................................................... 5
Methods ......................................................................................................................................................................... 6
Dreissenid Veligers .................................................................................................................................................... 6
D. gemintata............................................................................................................................................................... 7
P. antipodarum........................................................................................................................................................... 8
Water quality measurements ......................................................................................................................................... 8
Statistical Analysis ......................................................................................................................................................... 9
Results........................................................................................................................................................................... 9
Dreissenid Veligers .................................................................................................................................................... 9
D. gemintata..............................................................................................................................................................10
P. antipodarum..........................................................................................................................................................10
Discussion ....................................................................................................................................................................11
References Cited ..........................................................................................................................................................12
Table 1..........................................................................................................................................................................13
Figure 1 ........................................................................................................................................................................14
Figure 2 ........................................................................................................................................................................15
Figure 3 ........................................................................................................................................................................16
Appendix 1....................................................................................................................................................................17
3
Toxicity of Wildland Fire Foams to Invasive Aquatic
Species
By Edward E. Little 1 and Holly Puglis
1
U.S. Geological Survey
4
1
Introduction
2
Invasion by exotic species has been identified as one of the major threats to freshwater biodiversity (Dudgeon
3
and others, 2006). Exotic aquatic species have many invasive pathways including intentional and unintentional
4
spread by humans. One potential vector for the unintentional transfer of invasive aquatic species (hereafter,
5
invasive species) during the application of fire suppression chemicals that have been prepared with water
6
infested with invasive organisms.
7
Routine fire suppression activities during wildland fires often involve the use of fire retardants and fire
8
suppressant foams and gels. These are occasionally prepared at a location near the fire by mixing fire chemical
9
concentrates with water from natural sources such as lakes, ponds, streams, or reservoirs for helicopter dip-tank
10
applications (http://www.fs.fed.us/rm/fire/, last accessed 10/01/2014). The operations may result in water
11
obtained from one watershed applied to a different watershed, which may contribute to the spread of exotic
12
species.
13
Many federal agencies that are involved in fighting wildland fires already have guidelines in place to prevent
14
the spread of invasive species including sanitizing equipment with chemical disinfectants (typically quaternary
15
ammonia compounds or bleach are recommended), allowing equipment to thoroughly dry, and sanitizing
16
surfaces with hot water (National Interagency Fire Center, 2013; United States Department of Agriculture,
17
2013). There is also a possibility that the chemical products used in retardants, foams, and water enhancers may
18
be toxic to these invasive species, but little is known about the sensitivity of potentially invasive organisms to
19
these products during routine fire suppression applications.
5
20
Because of climate change and fuel accumulation, wildland fires in the western United States are predicted to be
21
more frequent and larger (National Wildlife Coordinating Group Executive Board, 2009). This may increase the
22
risk of the potential spread of aquatic invasive species by infesting firefighting equipment. Several of the most
23
virulent invaders in the western United States include, zebra and quagga mussels, Dreissena polymorpha and
24
Dreissena bugensis, (hereafter, dreissenids), didymo (Didymosphenia geminata) and New Zealand mudsnail
25
(Potamopyrgus antipodarum) (Viani and others, 2011). The primary objective of this study is to determine the
26
sensitivity of the dreissenid larvae (hereafter, veligers) D. geminata, and P. antipodarum to chemical fire
27
suppression foams for realistic contact times that would be expected during fire suppressant loading and
28
delivery. Because of the highly invasive nature of the previously listed species, all studies were carried out in
29
locations where the organisms are well established, thereby eliminating the risk of accidental release during
30
shipment or testing in Missouri.
31
32
Methods for conducting toxicity tests with invasive organisms
33
Fire suppression foams were obtained from the United States Department of Agriculture Forest Service and
34
were shipped to the Columbia Environmental Research Center (CERC) by way of overnight courier in sealed
35
containers. Upon receipt, shipping containers were inspected for damage and the security seals were inspected
36
with no evidence of tampering. The chemicals were stored in their shipping containers at room temperature in a
37
secured laboratory at CERC. The chemicals and manufacturers are as follows: Chemguard First Class is
38
manufactured by Chemguard, Inc. (Masfield, Texas), FIRST RESPONSE Class A Foam Concentrate and
39
PHOS-CHEK® WD881 Class A Foam Concentrate are manufactured by ICL PERFORMANCE PRODUCTS
40
LP (St. Louis, Missouri), and SILV-EX Plus is manufactured by Tyco Fire Suppression and Building Products
41
(Marinette, Wisconsin).
42
6
43
Toxicity tests were conducted with dreissenid larvae – referred to as veligers - of both quagga and zebra
44
mussels. Veligers of both species were collected from the Detroit River in Detroit, Michigan. No attempt was
45
made to sort them by species as this would increase handling stress. The veligers were held in an incubator for
46
at least 12 hours to acclimate to room temperature before the start of any test. The exposures to fire suppressant
47
foams were conducted at Wayne State University, Detroit in static conditions using filtered Detroit River water
48
at 21 degrees centigrade (ºC). Testing chambers were 300 microliter (µ/L) wells in a 96-well well plate. We
49
made 500-milliliter (mL) stock solutions by mixing 15 mL, 25 mL, and 50 mL of fire suppression foam into
50
485 mL, 475 mL, and 450 mL of filtered Detroit River water to make 3-, 5-, and 10- percent stock solutions,
51
respectively. Filtered Detroit River water was used as a control. The wells were stocked with at least one veliger
52
in about 200 µL of stock solution or Detroit River water. There were 12 replicates for each treatment. After 10-
53
15, and 45-60 minutes, an inverted microscope with cross polarized light filter was used to locate each veliger
54
then the organism was observed for signs of life without the polarizing filter at a magnification of 200X.. Each
55
veliger was observed for at least 30 seconds. If there were no signs of life, such as internal motion, after 30
56
seconds, the veliger was recorded as dead.
57
Exposures of D. geminata to fire suppression foams were conducted with 2-3 cubic millimeter (mm3) segments
58
of freshly collected D. geminata mats. The mats were collected from a spring fed inflow in the South Boulder
59
Creek in El Dorado Springs, Colorado. The exposures were conducted at the University of Colorado-Boulder in
60
static conditions in South Boulder Creek water (appendix 1) at 6 ºC. Testing chambers were 30 ml polystyrene
61
cups. Fire chemical stock solutions containing the commercial formulations were prepared with South Boulder
62
Creek water and adjusted for percent commercial formulation to achieve 3-, 5-, and 10-percent fire chemical
63
treatments. South Boulder Creek water was used as a control. Each cup was stocked with one mat segment and
64
20 mL of the appropriate stock solution or control water. Mat segments were exposed to each treatment for 10-
65
15 minutes or 45-60 minutes. There were four replicates for each treatment at each exposure time. Following
66
exposure, each segment was rinsed with deionized water to remove the fire chemical treatment and placed in
7
67
scintillation vials with 10 mL of 0.004 percent neutral red dye solution. To determine viability, an inverted
68
microscope was used to view the cells at a magnification of 400x (Kilroy, 2005).
69
70
P. antipodarum snails were collected from a 12 ºC spring fed stream in Astoria, Oregon. Animals were
71
kept in buckets overnight to be brought up to room temperature at 17 ºC. Exposures were conducted at Astoria
72
High School in static conditions in spring fed stream water collected at the high school fish hatchery (appendix
73
1) at 17 ºC. Test chambers were 30-mL polystyrene cups. Fire chemical stock solutions containing the
74
commercial formulations were prepared with stream water and adjusted for percent commercial formulation to
75
achieve 3-, 5-, and 10-percent fire chemical treatment. Stream water was used as a control. Chambers were pre-
76
rinsed with deionized water and 20 mL of the appropriate stock solution were added to each chamber. Snails
77
were exposed for 10-15 minutes or 45-60 minutes. There were four replicates for each chemical treatment at
78
each exposure time. Five snails were randomly placed on small segments of 1-mm fiberglass screening. The
79
screen segments were floated in petri dishes containing spring water during this procedure. One fiberglass
80
screen segment was randomly added to each chamber. Following exposure, each chamber was carefully
81
decanted through a section of fiberglass screening. Snails were gently rinsed with stream water and placed in
82
recovery chambers, 30-mL polystyrene cups, filled with 20 mL of control water (stream water). After 48 hours,
83
snails were placed under dissection scopes to look for signs of life at 10-20x magnification. Each snail was
84
viewed for as much as 5 minutes. If no movement was detected, the snail was gently prodded. Snails were
85
recorded as dead if they did not move after 5 minutes or after prodding.
86
87
Water Quality Measurements
88
Water samples collected at the onset of the exposures were shipped on ice overnight to CERC, where the
89
samples were analyzed for hardness, alkalinity, and total ammonia as described in Kemble and others (1993).
90
Temperature, specific conductance, and pH were measured at the time of the tests. Water quality variables
8
91
remained within acceptable ranges throughout all tests, however the total ammonia concentration, alkalinity,
92
and specific conductivity increased with increasing concentrations of Chemguard First Class and SILV-EX Plus
93
(table 1). Conductivity also increased for First Response and PHOS-CHEK WD881 and alkalinity increased for
94
PHOS-CHEK WD881.
95
96
97
Statistical Analysis
Dreissenid veliger survival was tested for differences at each interval between control and treatments
98
using Fisher’s Exact Tests (O’Rourke and others, 2005).. D. geminata survival was tested for differences
99
between control and 10 percent fire foam treatments after the 45-60-minute exposure endpoint with 1 tailed, t-
100
tests. D. geminata survival data were arcsin square root transformed before analysis. The analysis was limited to
101
the 10 percent treatment because the organisms were unaffected by lower concentrations. D. geminata survival
102
data also were tested for normality and homogeneity of variances. The appropriate t-test (equal or unequal
103
variances test) was used. To test for the effects of concentration and contact time, P. antipodarum survival was
104
analyzed with two-way ANOVAs and tested for normality and homogeneity (O’Rourke and others, 2005).
105
107
Results indicate that fire foam suppression chemicals will not eliminate invasive
organisms
108
Survival of dreissenid veligers was significantly reduced compared to controls after a 10 minute exposure at all
109
concentrations of Chemguard First Class. Only one veliger survived in the 3 percent treatment and zero
110
veligers survived in the 5 and 10 percent treatments (fig. 1). First Response did not significantly reduce survival
111
in any concentrations after 10-15 minutes but it did significantly reduce survival in all concentrations after 45-
112
60 minutes when compared to survival in the control treatment (fig. 1). PHOS-CHEKWD881 significantly
113
reduced survival (p< 0.01) in all concentrations after 10-15 minutes when compared to survival in the control
114
treatment with only one veliger surviving the 5 percent treatment. After 45-60 minutes, there were no surviving
106
9
115
veligers in any of the PHOS-CHEK WD881 treatments.
116
SILV-EX Plus significantly reduced survival (p<0.01) in the 5- and 10 percent concentrations after 10-15
117
minutes and in all concentrations after 45-60 minutes when compared to the control treatment with only one
118
veliger surviving the 3 percent SIL-EX Plus treatment after 45-60 minutes.
119
120
121
D. geminata
Chemguard First Class did not significantly reduce the number of viable cells in the 10 percent treatment
122
after 10-15 minute or 45-60 minute exposures when compared to cells in the control treatment (p=0.9213, fig.
123
2). There was no significant reduction in cell viability between D. geminata segments treated with 10 percent
124
First Response and the control treatment after 10-15 minute or 45-60 minutes. PHOS-CHEK WD881 did not
125
significantly reduce the number of viable cells in the 10 percent treatment after 10-15 minutes or 45-60 minutes
126
when compared to cells in the control treatment (p=0.4539). SILV-EX Plus significantly reduced the number of
127
viable cells in D. geminata segments treated with the 10 percent solution after 45-60 minutes compared to the
128
number of viable cells in segments in the control treatment with an approximately 18 percent reduction in viable
129
cells in the treated segments (p=0.0092). The 10-15 minute SILV-EX Plus exposures did not significantly
130
reduce the number of viable cells.
131
132
Chemguard First Class did not significantly reduce survival of P. antipodarum after 10-15 minutes or
133
45-60 minutes (p=0.2008, fig. 3). First Response did significantly reduce survival after 45-60 minutes with an
134
approximately 15 percent reduction in the 10 percent treatment (p=0.0346). There was no mortality in any
135
PHOS-CHEK WD881 treatments after 10-15 or 45-60 minutes. SILV-EX Plus did not significantly reduce
136
survival of P. antipodarum after 10-15 or 45-60 minutes (p=0.4262.)
137
10
138
139
Discussion
The objective of this study was to determine if any of the four fire suppression foams tested could be
140
used on firefighting equipment to prevent the spread of three potentially invasive species, including the
141
dreissenid zebra and quagga mussels, Dreissena polymorpha and Dreissena bugensis; didymo, Didymosphenia
142
geminata; and New Zealand mudsnail, Potamopyrgus antipodarum. Our research demonstrates that none of the
143
foams would function as an effective sanitizer for all aquatic invasive species.
144
Of the three species tested, dreissenid veligers were the most sensitive to the foams. Except for First
145
Response, all of the foams were 100 percent lethal to the veligers after 45-60 minutes of exposure in 5- or 10
146
percent solutions. A 10-15 minute exposure to a 5- or 10 percent solution of Chemguard was sufficient to
147
completely kill all veligers in this study. None of the foams would protect against the transfer of P. antipodarum
148
or D. geminata as the largest reduction in survival for either species in this study was 18 percent. Except for P.
149
antipodarum, we did not assess survival after transferring the organism from the fire suppression foams to
150
control water. Shorter contact times may have proven more lethal after some amount of recovery time, as
151
Britton and Dingman (2011) determined when exposing zebra and /quagga mussel veligers to quaternary
152
ammonia compounds. Britton and Dingman (2011) determined that survival of zebra and quagga mussel
153
veligers dramatically decreased after 60 minutes in control water following a 5 or 10 minute exposure to a 3
154
percent solution of a quaternary ammonia solution. Although we did not assess survival following a recovery
155
time for zebra and quagga mussel veligers or for D. geminata, our second contact time at 45-60 minute) was
156
much longer than exposure periods used by Britton and Dingman (2011), so it is unlikely that mortality would
157
have been greater if the organisms were placed in control water for the remaining time.
158
Current guidelines in the USFS Intermountain Region Technical Guidance on Preventing Spread of
159
Aquatic Invasive Organisms Common to the Intermountain Region (United States Department of Agriculture,
160
2013) list effective methods of control for all three of the organisms tested in this study. Based on our results,
161
fire suppression foams do not appear to prevent the spread of these invasive species.
11
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186
187
References Cited
American Society for Testing and Materials (2006) ASTM guide E729–96 (2002) Standard guide for conducting acute toxicity tests
with fishes, macroinvertebrates, and amphibians. In: Annual book of ASTM standards, vol 11.06. ASTM, West
Conshohocken,PA, pp 66-87
Britton, D.K., and Dingman, S., 2011, Use of quaternary ammonium to control the spread of aquatic invasive species by wildland fire
equipment, Aquatic Invasions, v. 6, no. 2, p.169–173.
Dudgeon, D., Arthington, H., Gessner, M.O., Kawabata, Z., Knowler, D.J., Leveque, C., Naiman, R.J., Prieur-Richard, A., Soto, D.,
Stiassny, M.L.J., and Sullivan, C.A., 2006, Freshwater biodiversity—Importance, threats, status and conservation challenges:
Biological Reviews of the Cambridge Philosophical Society, v.81, no. 2, p. 163–182.
Kemble, N.E., Brumbaugh, W. G., Brunson, E. L., Dwyer, F. J., Ingersoll, C. G., Monda, D. P.,and others, 1993, Sediment toxicity, in
Ingersoll, C.G., Brumbaugh, W.G., Farag, A.M., La Point, T.W., and Woodward, D.F., 1993, Effects of metal contaminated
sediment, water, and diet on aquatic organisms, U.S. Fish and Wildlife Service and University of Wyoming , Final report for
the U.S. Environmental protection Agency, Milltown Endangerment Assessment Project, for the 99 p. plus appendixes.
Kilroy, C., 2005, Tests to determine the effectiveness of methods for decontaminating materials that have been in contact with
Didymosphenia geminata: Christchurch, New Zealand, National Institute of Water and Atmospheric Research Ltd, NIWA
Client Report CHC2005-004, 36 p.
National Interagency Fire Center, 2013, Standards for fire and fire aviation operations: Boise, Idaho, National Interagency Fire Center,
Standards for fire and fire aviation operations task group, NFES 2724, 379 p.
National Wildfire Coordinating Group Executive Board, 2009, Quadrennial Fire Review 2009: Boise, Idaho, 62 p.
O'Rourke, N., Hatcher, L., and Stepanski, E.J., 2005, A step-by-step approach to using SAS for univariate and multivariate statistics
(2nd ed.): Cary, Nc., SAS Institute Inc., 514 p.
United States Department of Agriculture, 2013, Preventing spread of aquatic invasive organisms common to the Intermountain
Region, Technical Guidelines for Fire Operations: Ogden, Utah, U.S. Forest Service, 11 p.
Viani, L.O., Taitc C., and Heimowitz, P., 2011, The invasion of western waters by non-native species—Threats to the west: The
Western Regional Panel on Aquatic Nuisance Species, 8 p.
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189
192
193
194
195
196
197
190
191
A
0%
3%
5%
10%
Proportional survival
1.0
0%
3%
5%
10%
B
0.8
*
0.6
*
*
0.4
0.2
* *
*
0.0
*
*
*
* **
**
CG-FC
FR
PC-WD
CG-FC
SILV-EX
Chemical
FR
* **
**
PC-WD
SILV-EX
Chemical
Figure 1. Survival of dreissenid veligers in four fire foams after A) 10-15 minutes and B) 45-60 minutes.
Asterisks indicated statistically significant reduction in survival compared to control treatment.CG-FC –
Chemguard First Class; FR- First Response; PC-WD – PHOS-Chek WD881; SILV-EX-SILV-EX Plus.
13
220
221
222
223
224
225
Proportion of viable cells
198
199
Control
10% 200
201
1.0
202
203
*
0.8
204
205
206
0.6
207
208
0.4
209
210
211
0.2
212
213
0.0
214
CG-FC
FR
PC-WD
SILV-EX
215
216
Chemical
217
218
219
Figure 2. Mean (±1 SD) proportion of viable D. geminata cells in four different fire foams after a 45-60 minute
exposure. Asterisk indicates a significant difference in cell viability from control segments. CG-FC –
Chemguard First Class; FR- First Response; PC-WD – PHOS-CHEK WD881 ; SILV-EX - SILV-EX Plus.
14
250
251
252
253
254
255
256
257
Proportional survival
226
227
0%
10% 228
229
1.0
*
230
231
232
0.8
233
234
0.6
235
236
237
0.4
238
239
240
0.2
241
242
243
0.0
244
Chemguard
PC-FR
PC-WD
Silv-Ex
245
Chemical
246
247
248
249
Figure 3. Mean (±1 SD) proportion of P. antipodarum survival in four fire suppression foams after a 45-60minute exposure and a 48-hour recovery period in control water . Asterisk indicates a significant difference in
survival from control treatment. CG-FC – Chemguard First Class; FR- First Response; PC-WD – PHOSCHEKWD881; SILV-EX-SILV-EX Plus.
258
15
259
260
261
262
263
264
265
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267
268
269
270
271
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273
274
275
276
277
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300
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302
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304
305
APPENDIX 1
Test Procedures
Definitive toxicity tests with Didymosphenia geminata, dreissenid veligers, and P. antipodarum were conducted
according to procedures described in ASTM Guide E 729 – 96 (2006), Standard Guide for Conducting Acute Toxicity
Tests with Fishes, Macroinvertebrates, and Amphibians and are summarized below.
Test type and duration:
Static acute, 1 hour
Test solution volume:
10 microliters, dreissenid veliger test
15millilitersl, Didymosphenia geminata test
20 milliliters, Potamopyrgus antipodarum test
Animals per chamber:
1 veliger per chamber, dreissenid veliger test
1 mat segment per chamber, Didymosphenia geminata test
5 snails per chamber, Potamopyrgus antipodarum test
Feeding:
None
Photoperiod:
16 hours light/8 hours dark
Test substance:
Chemguard First Class FC
FIRST RESPONSE Class A Foam Concentrate
PHOS-CHEK WD881 Class A Foam Concentrate
SILV-EX Plus
Exposure water:
Filtered Detroit River Water, dreissenid veliger test
Filtered South Boulder Creek Water, Didymosphenia geminata test
Filtered spring fed Astoria stream water, Potamopyrgus antipodarum test
Replication:
Twelve replicate chambers/treatment for tests with dreissenid veligers
Four replicate chambers/treatment for tests with Didymosphenia geminata
Four replicate chambers/treatment for tests with Potamopyrgus antipodarum
Treatments:
Three chemical dilutions and source water control
Test conditions:
21+ 1 oC (Dreissenid veligers), 6 + 2 oC (D. geminata), 17+ 1 oC (P. antipodarum)
Test Monitoring:
Measurements in all treatments for dissolved oxygen, temperature, pH, alkalinity, and
hardness
Test endpoints:
Survival after 10-15 minutes and 45-60 minutes
16
306
Table 1. Water quality variables measured after 1 hour static exposures of veligers of zebra mussels
307
(Dreissena polymorpha) and quagga mussels (Dreissena bugensis), didymo (Didymosphenia geminate) and New
308
Zealand mudsnail (Potamopyrgus antipodarum). Chemguard First Class (CG-FC), First Response (FR), PHOS-
309
CHEK WD881 (PC-W), SILV-EX Plus (SILV-EX), percent (%), degrees centigrade (°C), microsiemens per
310
centimenter (µS/cm), Standard Unit (SU), calcium carbonate (CaCO3), ammonia (NH3 ), milligrams per liter
311
(mg/L), standard deviation in parentheses, - data not collected.
312
Dreisena polymorpha and Dreissena bugensis
Fire
Foam
Concentration
(%)
Temperature
(°C)
Conductivity
(µS/cm)
pH (SU)
Alkalinity
(as CaCO3)
Hardness (as
CaCO3)
Total NH3
(mg /L)
Control
0
21
219
8.1
80
96
0.07
CG-FC
3
21
1231
7.3
112
102
197
5
21
1810
7.3
136
100
371
10
3
21
3290
7.4
192
94
670
21
1124
7.8
98
104
0.04
5
21
1513
7.6
102
102
0.02
10
21
2640
7.4
114
100
0.03
3
21
1425
8.0
138
108
0.07
FR
PC-W
SILV-EX
5
21
2250
8.0
180
96
0.22
10
21
4190
7.9
262
98
0.09
3
21
641
7.8
164
108
10.2
5
21
865
7.8
204
106
17.7
10
21
1655
7.7
342
96
39.4
313
17
314
315
316
317
Didymosphenia geminata
Concentration
(%)
Temperature
(°C)
Conductivity
(µS/cm)
pH
(SU)
Alkalinity as
CaCO3)
Hardness (as
CaCO3)
Total
NH3
(mg /L)
Control
0
6
(0)
52.5
(0.4)
7.1
(0.03)
21
(1.4)
20
(0)
0.07
(0.01)
CG-FC
10
6
3190
7.28
140
22
866
FR
10
6
2560
6.71
58
26
0.05
PC-W
10
6
3960
7.38
208
20
0.04
SILV-EX
10
6
1540
7.49
306
22
39.3
Temperature
(°C)
Conductivity
(µS/cm)
pH
(SU)
Alkalinity as
CaCO3)
Hardness (as
CaCO3)
17
(1)
17
(1)
17
(1)
17
(1)
17
(1)
110.4
(1.0)
6.90
(0.1)
7.24
(0.1)
7.1
(0.01)
7.4
(0.01)
8.1
(0.01)
15
(2.0)
94
(2.8)
24
(0)
98
(2.8)
222
(2.8)
22
(2.3)
24
(0)
28
(0)
26
(2.8)
28
(0)
Fire Foam
Potamopyrgus antipodarum
Fire Foam
Control
Concentration
(%)
0
CG-FC
10
FR
10
PC-W
10
SILV-EX
10
-
318
18
Total
NH3
(mg /L)
0.03
(0.002)
-