Bis(methylcyclohexyl) phthalate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

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 with acceptable restrictions

Remarks:

vehicle was used

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: GG01
- Purity: 99.9% (GC method)

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: 100 mg test substance was accurately weighed and dissolved into 200 mg dimethylformamide. Aliquot (4800 mg) of dispersing agent (HCO-40) was then added and mixed fully. The mixture was eventually made to 100 mL by volumetric flask using culture media, and the final concentration was 1000 mg/L.
Aliquot of culture media was added into each test container. Appropriate amount of vehicle was then added, and the concentration of 100 mg/l was obtained. Thereafter, the solution of test substance for test group was prepared with the concentration of 2.00 mg/L. Only culture media was used for the blank control, and vehicle dissolved in culture media to 100 mg/l was treated as vehicle control.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Dimethylformamid, HCO-40
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)): 100 mg/L

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Hardness:

-

Test temperature:

23 ± 2 °C

pH:

-

Dissolved oxygen:

-

Nominal and measured concentrations:

Nominal: 2 mg/L

Details on test conditions:

not specified

Reference substance (positive control):

not specified

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Validity criteria fulfilled:

yes

Conclusions:

The test substance is not toxic to aquatic algae within its limit of solubility in water.

Executive summary:

One study was performed to assess the toxicity of dicyclohexyl phthalate to the aquatic algae Pseudokirchnerella subcapitata.The study was conducted under GLP and according to OECD guideline 201. The study was performed in a closed static system. Algae were exposed to the test substance at a limit test concentration of 2 mg/L using a vehicle to fascilitate exposure. Test substance analytics confirmed the nominal concentrations. The 72h-EC50 is determined to be > 2 mg/L and the 72h-NOEC value is determined to be >= 2 mg/L.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

vehicle was used

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
The analogue justification document is attached to chapter 13.

Reason / purpose for cross-reference:

read-across source

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: GG01
- Purity: 99.9% (GC method)

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Conclusions:

The test substance is not toxic to aquatic algae within its limit of solubility in water.

Description of key information

No toxicity observed within the limit of solubility in water (72h-EC50 > 2 mg/L/ 72h-NOEC >= 2 mg/L (nominal, vehicle) for growth rate of Pseudokirchnerella subcapitata (OECD 202, read across))

Additional information

Since no studies assessing the toxicity of Bis(methylcyclohexyl) phthalate (CAS 27987-25-3) to aquatic algae is available, in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 Grouping of substances, a read-across to the structurally related source substance Dicyclohexyl phthalate (CAS 84-61-7) was conducted. The analogue justification document is attached to chapter 13.

The study with the read across substance was performed by the Japanese environmental agency under GLP according to OECD guideline 201 using Pseudokirchnerella subcapitata as test organism (MOE 2000). Dimethylformamid, HCO-40 were used to fascilitate the solubility of the substance in the test solution. A limit test concentration of 2 mg/L was tested. The nominal concentration was varified analytically. The 72h-EC50 value is deternined to be > 2 mg/L and the 72h-NOEC value is determined to be >= 2mg/L. Thus, the substance is not harmful to aquatic algae up to its limit of solubility in water. Based on the high structural similarity which leads to similar environmental behaviour and ecotoxicity this conclusion can also be considered true for the target substance Bis(methylcyclohexyl) phthalate.