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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Japanese government peer-reviewed the documents, audited selected studies.

Data source

Reference
Reference Type:
review article or handbook
Title:
Unnamed
Year:
2000

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Supplier: KISHIDA CHEMICALS CO., Ltd (Lot No. D12358J)
Purity: >= 98 %

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
Test Organism:
-strain: ATCC-22662
-supplier: American Type Culture Collection
-acclimation: 3 days
-initial cell concentration: 1X10E+4 cells/mL

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h

Test conditions

Test temperature:
original test: 21.8 - 22.8 (mean 22.5) °C
supplemental test: 21.2 - 23.0 (mean 22.5) °C
pH:
original test: 7.0 - 7.3 at start, 8.1-8.6 at end of test
supplemental test: 7.3 - 7.5 at start, 8.9 - 9.0 at end of test
Dissolved oxygen:
no data
Salinity:
no data
Nominal and measured concentrations:
0, 1000 mg/L (original test, nominal) actual concentration measured and greater than 80% of the nominal concentration
0, 556 mg/L (supplemental test, nominal) actual concentration measured and greater than 80% of the nominal concentration
Details on test conditions:
TEST MEDIUM CHEMISTRY: OECD medium
TEST SYSTEM (closed system)
-exposure vessel type: 100 mL medium in a 300 mL Erlenmeyer flask with a porous plug
-number of replicates: 3
-test temperature: 21 - 25 degree C
-pH: no adjustment during exposure period
-intensity of irradiation: 4,000 - 5,000 lux
-photoperiod: continuous
-shaking: 100 rpm
TEST PARAMETER: cell concentration (cells/mL)
Reference substance (positive control):
yes
Remarks:
K2Cr2O7

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 1 000 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: actual concentration measured and greater than 80% of the nominal concentration
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
1 000 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: actual concentration measured and greater than 80% of the nominal concentration
Details on results:
Results:
Table 1 NOMINAL/MEASURED CONCENTRATION
-----------------------------------------------------------
Nominal Measured conc. (mg/L) conc.
(% of nominal) (mg/L) 0 hr* 72 hr**
-----------------------------------------------------------
Control <0.5 <0.5
1000 mg/L 1011 (101.1) 926 (92.6)

Control <0.5 <0.5
556 mg/L 599 (107.7) 556 (100.0)
-----------------------------------------------------------
*: initial **: final


EFFECT DATA/ELEMENT VALUES:
-area method: EbC50 (0 - 72hr ) > 1000 mg/L
NOEbC (0 - 72hr ) = 556 mg/L
-rate method: ErC50 ( 24 - 48hr ) > 1000 mg/L
NOErC ( 24 - 48hr ) = 1000 mg/L
ErC50 ( 24 - 72hr ) > 1000 mg/L
NOErC ( 24 - 72hr ) = 1000 mg/L

Table 2 AVERAGE CELL DENSITY OF Selenastrum capricornutum
-----------------------------------------------------------
Nominal conc. Cell Density (1x10E+4 cell/mL)
(mg/L) 0 hr 24 hr 48 hr 72 hr
-----------------------------------------------------------

Control 1.0 5.5 34.7 201.6
1000mg/L 1.0 5.0 30.6 197.3

Control 1.0 5.2 33.5 204.4
556mg/L 1.0 5.3 40.6 212.2
-----------------------------------------------------------
Table 3 AVERAGE GROWTH INHIBITION
-----------------------------------------------------------
Nominal Inhibition
conc. area method growth rate growth rate
(mg/L) (0-72hr)% (24-48hr)% (24-72hr)%
-----------------------------------------------------------

Control - - -
1000 mg/L 4.82 1.59 -2.08

Control - - -
556 mg/L -7.99 -9.36 -0.34
-----------------------------------------------------------
Results with reference substance (positive control):
REFERENCE SUBSTANCE: K2Cr2O7 EbC50 (72hrs) = 0.52 mg/L
Reported statistics and error estimates:
STATISTICS: F&T-test; Yukms StatLight #3 "Pairwise Comparisons" EA Japan

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
At a limit concentration of 1000 mg/l (nomial), methacrylamide showed no growth inhibition in an Algae, Growth Inhibition Test OECD 201.
ErC50 (72h) > 1000 mg/l (measured/nominal), NOErC = 1000 mg/l (measured/nominal)
Executive summary:

In a 72-hour acute toxicity study, the cultures of Pseudokirchneriella subcapitata, strain ATCC-22662 were exposed to control and test item at nominal/measured concentrations of 1000 mg a.i./L in accordance with the Algae, Growth Inhibition Test, OECD 201  The NOEC and ErC50values based on growth inhibition were 1000 mg/l and > 1000 mg a.i./L, respectively.  The % growth inhibition in the treated algal culture as compared to the control ranged from -2.08 to 1.59 

There were no compound related phytotoxic effects.

This toxicity study is classified as acceptable and satisfies the guideline requirements for Algae, Growth Inhibition study.

Results Synopsis:

Test organism: Pseudokirchneriella subcapitata

Test type: static

72 -hr EC50: > 1000 mg/l

72 -hr NOEC: 1000 mg/l