Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
4 March 1987 - 6 March 1987
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report Date:
1987

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EPA OPP 72-2 (Aquatic Invertebrate Acute Toxicity Test)
Version / remarks:
U.S. EPA FIFRA, 40 CFR, Part 158.145 Guideline72-2 (1982)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
Batch No.: 60553, Purity: 94.5%,

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Measured values for each concentration of the test solutions were determined at the beginning and at the end of the study.

Test solutions

Vehicle:
yes

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Age of organisms at study initiation: first-instar (less than 24 hours old)

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Nominal and measured concentrations:

Nominal: 0.0024, 0.0048, 0.0095, 0.019, 0.038, 0.075, 0.150 and 0.300 mg/l
Measured: 0, 0.002, 0.0043, 0.010, 0.020, 0.040, 0.084, 0.180, and 0.340 mg/l

Results and discussion

Effect concentrationsopen allclose all
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.009 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Key result
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
0.002 < mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mortality
Details on results:
The measured concentrations of Fenitrothion yielded an average of 104 + 12% of the nominal concentrations for this 48-hours study.

Any other information on results incl. tables

Mortality* and behavioural observations

 

Mean measured concentrations

(Nominal concentrations) (mg/l)

number of daphnids

24 hr

48 hr

Mortality*

Observations

Mortality*

Observations

Control

20

0

20N

0

20N

Solvent control

20

0

20N

0

20N

0.0020  (0.0024)

20

0

20N

1

3N

16ERR

0.0043  (0.0048)

20

0

20ERR

1

4ERR

8OB/ERR

7OB/Q

0.010    (0.0095)

20

0

13OB/Q

5OB/ERR

2ERR

10

10OB/Q

0.020    (0.019)

20

3

13OB/Q

4OB/ERR

20

---

0.040    (0.038)

20

0

20OB/Q

20

---

0.084    (0.075)

20

1

13OB/Q

6OB/Q/C

20

---

0.180    (0.150)

20

6

14OB/Q/C

20

---

0.340    (0.300)

20

11

9OB/Q/C

20

---

N= Normal; ERR= Erratic Movement; C= Clumping of Daphnia; OB= On Bottom; Q= Quiescent

*: Since in this study the mortality was confirmed by checking for daphnid movement in response to gentle prodding with a glass pipe,

this “mortality” is equivalent to “immobilisation” which is defined in Directive 92/69/EEC Method C2.

Therefore the EC50value is estimated based on this mortality, namely immobilisation data.

 

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
Conclusion: 48hr-EC50: 0.0086mg/l, 48hr-NOEC: < 0.002mg/l
Executive summary:

The acute toxicity study of Penitrothion to Daphnia magna was assessed. Water quality parameters of temperature, dissolved oxygen and pH were measured at the termination of the test and were within acceptable limits. Analytical samples were taken at 0 and 48 hours of testing. 48hr EC50: 0.0086 mg/L, 48 hr NOEC: <0.002mg/L