Formaldehyde, oligomeric reaction products with 4,4'-isopropylidenediphenol and m-phenylenebis (methylamine)

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

A nominal amount of test item (638 mg) was added to the surface of 22 liters of test water to give the 29 mg/L loading rate. After the addition of the test item, the test water was stirred by magnetic stirrer using a stirring rate such that a vortex was formed to give a dimple at the water surface. The stirring was stopped after 95 hours and the mixture allowed to stand for 1 hour. Microscopic inspection of the WAF showed no micro-dispersions or undissolved test item to be present; however as a precaution the aqueous phase or WAF was removed by filtering through a glass wool plug. A wide bore glass tube, covered at one end with Nescofilm was submerged into the vessel, sealed end down, to a depth of approximately 5 cm from the bottom of the vessel. A length of Tygon tubing was inserted into the glass tube and pushed through the Nescofilm seal. A glass wool plug was inserted into the opposite end of the tubing and the WAF removed by mid-depth siphoning (the first 75-100 mL discarded) to give the 29 mg/L loading rate WAF. The glass wool precaution was used due to test item entering the siphon during the 0-Hour test preparation. Some of the test item settled on the bottom was disturbed and hence it was considered justifiable to filter the preparation through a glass wool plug.

The concentration and stability of the test item in the test preparations were verified by chemical analysis at 0, 24, 72 and 96 hours.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

14 degrees Celcius

pH:

7.3-7.7

Dissolved oxygen:

9.6-11.6

Key result

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 29 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

29 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

not specified

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated using the threshold approach and gave a 96-Hour LL50 value of greater than 29 mg/L loading rate WAF. The No Observed Effect Loading rate was 29 mg/L loading rate WAF.

Executive summary:

Introduction

A study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No. 203, "Fish, Acute Toxicity Test" referenced as Method C.1 of Commission Regulation (EC) No. 440/2008.

Methods

Due to the low aqueous solubility and complex nature of the test item, for the purposes of the test, the test medium was prepared as a Water Accommodated Fraction (WAF).

In accordance with the recommendations of REACh, the test was conducted according to the threshold approach recommended by ECHA. Using this approach the lowest EL50 value from either the Algal Growth Inhibition study or Acute Toxicity to Daphnia magna study is set as the threshold loading rate and a “Limit test” is conducted at this threshold loading rate. If no mortalities are observed this indicates that fish are not the most sensitive species and that the LL50 is greater than the threshold loading rate. The EL50 value for yield obtained from the Algal Growth Inhibition study (Envigo Study Number WR20XK) was the lowest of the EL50 values and hence the test was conducted at a single loading rate of 29 mg/L.

Seven fish were exposed to a Water Accommodated Fraction (WAF) of the test item, at a single nominal loading rate of 29 mg/L for a period of 96 hours at a temperature of 14 °C to 15 ºC under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

Results

Analysis of the freshly prepared 29 mg/L loading rate test preparations at 0 and 72 hours showed measured test concentrations to be 8.4 and 6.2 mg/L, respectively. There was no significant change in the measured concentrations aged or expired preparations at 24 and 96 hours.

Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

Exposure of rainbow trout to the test item gave LL50 values of greater than 29 mg/L loading rate WAF. The No Observed Effect Loading Rate was 29 mg/L loading rate WAF.

Description of key information

The acute toxicity of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated using the threshold approach and gave a 96-Hour LL50 value of greater than 29 mg/L loading rate WAF. The No Observed Effect Loading rate was 29 mg/L loading rate WAF.