Tin tetrachloride

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:

2009-11-06 to 2010-03-16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study followed OECD Guideline under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Tin tetrachloride

EC Number:

231-588-9

EC Name:

Tin tetrachloride

Cas Number:

7646-78-8

Molecular formula:

Cl4Sn

IUPAC Name:

tin tetrachloride

Details on test material:

- Name of test material (as cited in study report): Tin tetrachloride
- Physical state: Liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

In order to prevent possible precipitation of tin the pH of the samples was adjusted to a value of 2 using hydrochloric acid directly after sampling. These samples were stored in a refrigerator (4 ± 4 °C), protected from light until analysis was performed. Before measurement the biological and fortified samples were ultrasonicated for 5 min.
Sampling: Duplicate samples from the freshly prepared test medium of the only test concentration and the control were taken at the start of the test.
For the determination of the stability of the test item under the test conditions and of the maintenance of the test item concentration during the test period, duplicate samples from the test medium of the only test concentration and the control were collected at the end of the test (after 48 hours).

Test solutions

Vehicle:

no

Details on test solutions:

The test item was not well soluble in test water. To avoid physical effects of undissolved test item on Daphnia no concentration above the solubility limit of the test item in test water was tested. Therefore, a supersaturated stock solution of 100 mg test item/L was prepared by suspending 44.8 µL of test item in 1000 mL of test water for preparing the test concentration. The pH was adjusted with 2M NaOH from 3.4 to 7.9. The stock suspension was stirred for 24 hours to dissolve as much test item as possible. Then, the undissolved test item was separated by filtration (Sartobran Capsule 0.45 µm) and the filtrate was used as test medium. The test media were prepared just before introduction of Daphnia (= start of the test).

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna (Straus), clone 5
Age at Test Start: From 7.25 to 23.25 hours old
Sex: Female
Origin: The Daphnia introduced in the test were taken from our in house laboratory culture.
Breeding Conditions: The Daphnia were bred in the laboratories of IBACON under similar temperature and light conditions as used in the test. The cultivation of the parental Daphnia was performed in reconstituted water of a similar quality with regards to pH, the constituent salts and total hardness as the test water used in the test (see 6.5). The test organisms were not first brood progeny. The Daphnia in the stock culture were fed at least all working days with green algae (Desmodesmus subspicatus) freshly grown in the laboratories of IBACON.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Details on test conditions:

Test Environment: Controlled environment room
Measurement of pH, Dissolved Oxygen and Water Temperature: At test start and end the pH-values and the dissolved oxygen concentrations were determined in the test media of the only test concentration and the control. The water temperature was measured in the test media of the only test concentration and the control at test start and in one control beaker at the end of the test.
pH-Values: 7.8 to 7.9 at test start; 7.8 at test end; and thus the pH-value did not vary by more than 1.5 units
Oxygen Concentration: 9.1 to 9.2 mg/L at test start; 9.2 to 9.5 mg/L at test end
Water Temperature: 19 to 20 °C at test start; 21 °C at test end
Light Regime: 16 h light : 8 h dark
Light Intensity: The light intensity was 250 - 270 lux (measured once during the test).
Recording: Test conditions were recorded with suitable instruments and documented in the raw data.
Test vessels (Type and Size): Glass beakers of 100 mL volume containing approximately 80 mL of test medium. The test vessels were covered with a lid to reduce the loss of water due to evaporation and to avoid the entry of dust into the solutions.
Introduction of Individuals: 20 Daphnia per control and test concentration, divided into 4 groups of 5 animals, each group in 80 mL test medium

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, regular tests

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Loading rate

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Loading rate

Basis for effect:

mobility

Details on results:

BIOLOGICAL RESULTS
Signs of Intoxication after 24 Hours: After 24 hours in the control and in the only test concentration of nominal 100 mg test item/L no immobilisation of the test animals was observed.
Results after 24 Hours:
EL50 [mg test item/L]: > 100
95 % Confidence Values [mg test item/L]: n.d.
NOELR [mg test item/L]: >= 100
LOELR [mg test item/L]: > 100
Values refer to nominal test concentrations.

Signs of Intoxication after 48 Hours: After 48 hours of exposure no immobilisation of the test animals was observed in the control and in the only test concentration of nominal 100 mg test item/L (see Table 2).
Results after 48 Hours:
EL50 [mg test item/L]: > 100
95 % Confidence Values [mg test item/L]: n.d.
NOELR [mg test item/L]: >= 100
LOELR [mg test item/L]: > 100
Values refer to nominal test concentrations.
Appearance of the Test Item in Test Water: No remarkable observations

ANALYTICAL RESULTS
Determination of the Tin: Based on the results of AAS measurements the concentration of the tin was determined using a calibration curve.
Calibration Range: 0.005 to 0.08 mg Sn/L
Linearity of Response: Correlation of extinction of different standard solutions with their corresponding concentrations, using a linear regression
Regression Coefficient (r2): At least 0.9963
Typical Calibration Curve: y = 0.4917 * x – 22.4497 (see also Figure 1)
Limit of Detection: 0.0076 mg Sn/L
Limit of Quantification: 0.01 mg Sn/L
Mean Recovery in the Fortified Samples: 85 % (n = 12, RSD 11 %) (see Table 7)
Mean Recovery in the Test Samples: All values are below the limit of detection of the analytical method (see also Table 7).
Results: The quantification of the test item in the test media was not possible. Due to the low water solubility of the test item the concentrations of test item in the test media were below the limit of detection of the analytical method.

Results with reference substance (positive control):

- EC50 (48h): 0.914 m/L

Reported statistics and error estimates:

not applicable

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The toxic effect of the test item Tin Tetrachloride to Daphnia magna was assessed in a static limit-test. The 48-hour NOELR was determined to be >= 100 mg test item/L (nominal). The 48-hour EL50 value was determined to be > 100 mg test item/L (nominal).

Executive summary:

Tin tetrachloride was investigated for acute toxicity to Daphnia magna in a static limit test according to OECD 202 under GLP. The 48-hour NOELR was determined to be >= 100 mg test item/L (nominal). The 48-hour EL50 value was determined to be > 100 mg test item/L (nominal). The validity criteria were fullfilled.