Phenol, mono- + distyrenated (MSP+DSP)

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given; guideline study (OECD TG 211); test was performed by a laboratory with a high reputation for delivery of robust data.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material (as cited in study report): Phenol, styrenated; Mono (or di or tri)-(alpha-methylbenzyl) phenol
- no further information

Analytical monitoring:

yes

Details on sampling:

- no data reported

Vehicle:

not specified

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- no further information

Test type:

not specified

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Nominal and measured concentrations:

- graduate doses of test substance were applied. Individual concentrations are not reported.

Details on test conditions:

- no data reported

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.2 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

1.5 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

reproduction

Details on results:

Results are reported without any detail in databases (CHRIP/J-CHECK) of the National Institute of Technology and Evaluation (NITE) of Japan.

Validity criteria fulfilled:

not specified

Conclusions:

In a test according to OECD TG 211, the 21 d NOEC and EC50 of phenol, styrenated to Daphnia (endpoint reproduction) were determined to be 0.2 and 1.5 mg/L, respectively.

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

GLP compliance:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): distyrenated phenol
- Analytical purity: 97.21%

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Test substance solutions were prepared as water accommodated fractions (WAF). A saturated stock solution was made for each test substance renewal by direct addition of test substance to dilution water followed by low energy stirring for 48 hours. Test solutions were prepared by diluting the stock solution to corresponding test concentrations

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Feeding during test: yes
- Frequency: at least five times per week

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test temperature:

18 - 22 °C

Nominal and measured concentrations:

nominal [µg/L]: 18.75 37.5 75.0 150 300
measured [µg/L]: 20.1 35.7 56.9 115 249

Details on test conditions:

TEST SYSTEM
- Test vessel: fill volume 50 mL
- Renewal rate of test solution (frequency/flow rate): three times per week
- No. of organisms per vessel: 1 female
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): no data
- No. of vessels per vehicle control (replicates): no data
- Biomass loading rate:

OTHER TEST CONDITIONS
- Photoperiod: 16/8 hrs light/ dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): offspring production, parent mortality

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study: yes (preliminary acute immobilisation study and 16-day reproduction study)

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.115 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: reproduction and parental immobilisation

Details on results:

No statistically significant effects were observed in the lowest four test concentrations.
At 249 μg/l, a 73 per cent reduction in offspring production and 90 per cent effect on parent mortality was observed.

Validity criteria fulfilled:

yes

Conclusions:

In a valid 21-d Daphnia magna reproduction test according to OECD TG 211 conducted under GLP conditions, a NOEC of 0.115 mg/L (measured concentrations) was determined based on both reproduction and parental immobilisation.

Description of key information

Long-term toxicity of phenol, mono- & distyrenated to aquatic invertebrates was examined in two studies according to OECD TG 211 using phenol, styrenated and distyrenated phenol, a ca. 20 to 40 % component of phenol, mono- & distyrenated, as test substances. Resulting NOEC are close together.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.115 mg/L

Additional information

For the assessment of the long-term toxicity of phenol, mono- & distyrenated to aquatic invertebrates, two studies have been located. Both were performed according to OECD TG 211. One is a GLP study using distyrenated phenol as test substances ((Noack/NOACK 2006). Phenol, mono- & distyrenated (Novares LS 500) contains between ca. 20 and 40 % of the 2,4- isomer of this substance. Thus it is justified to use test results for this substance as evidence in characterising phenol, mono- & distyrenated.

The other study was carried out under the Chemical Substance Control Law in order of the National Institute of Technology and Evaluation/Ministry of the Environment of Japan (CHRIP/NITE 1997). The study was performed according to OECD TG 211 and is reported in the Japanese databases CHRIP/J-CHECK (CHRIP/NITE 1997). Details on test performance and results are not available from the database. Nevertheless, results are considered valid as studies from NITE have a high reputation to provide reliable data. The substance tested was phenol, styrenated (CAS 61788-44-1). Composition of the test substance is not reported, but from the substance name under the Chemical Substance Control Law (mono (or di or tri)-(alpha-methylbenzyl)phenol) it can be concluded that the test substance is a mixture of mono-, di-, and tristyrenated phenol. Similarity with Novares LS 500 is considered to be adequate to use data from this test as supporting evidence for the aquatic toxicity characterisation of Novares LS 500.

Results of both studies are presented in the following table.

 

Study	21d EC50 [mg/L]	21d NOEC [mg/L]
NOACK 2006	-	0.115
CHRIP/NITE 1997	1.5	0.200

 

NOEC of both test are close together. Distyrenated phenol appears slightly more toxic to invertebrates than the composite substance phenol, styrenated containing mono-, di-, and tristyrenated phenol. As conservative approach, the lower of the two values is selected for further consideration.