(1-methylethylidene)di-4,1-phenylenetetraphenyl diphosphate

Toxicity to aquatic algae and cyanobacteria

Administrative data

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:

other: see 'Remark'

Remarks:

The data comes from a report of NATIONAL INDUSTRIAL CHEMICALS NOTIFICATION AND ASSESSMENT SCHEME (NICNAS), which is administered by the National Occupational Health and Safety Commission (NOHSC) of Australian Commission. Also the Data were determined by the OECD guideline.

Data source

Reference

Reference Type:

review article or handbook

Title:

Phosphoric acid, (1-methylethylidene) di-4,1-phenylene tetraphenyl ester (Fyrolflex BDP)

Author:

National Occupational Health and Safety Commission (Australia)

Year:

2000

Bibliographic source:

In:NATIONAL INDUSTRIAL CHEMICALS NOTIFICATION AND ASSESSMENT SCHEME

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

425-220-8

EC Name:

-

Cas Number:

5945-33-5

Molecular formula:

C39H34O8P2

IUPAC Name:

(1-methylethylidene)di-4,1-phenylenetetraphenyl diphosphate

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Six replicate tests were conducted in 250 mL Erlenmeyer flasks, together with three control flasks containing no chemical. Three solvent controls (ie water and the appropriate amount of dimethylformamide) were also run. Each flask contained 100 mL of the test medium, and the flasks were continuously agitated to maintain the algal cells in suspension.

Test solutions

Vehicle:

yes

Details on test solutions:

The test substance was firstly dissolved in dimethylformamide to produce a 10 g/L solution. An aliquot of this was added to the test vessels in order to produce the indicated nominal concentrations.

Test organisms

Test organisms (species):

Selenastrum sp.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Hardness:

around 100 mg/L as CaCO3

Test temperature:

21 ± 1°C

pH:

The pH of the test solutions increased from around 8.0 at the start of the period, to around 10 after 72 hours.

Dissolved oxygen:

between 9.4 and 10.1 mg/L

Nominal and measured concentrations:

Analysis of the solutions for the test compound after 72 hours indicated approximately 74% recovery (compared with a nominal initial concentration of 1 mg/L).

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Details on results:

The growth of algal biomass was determined over the test period by measurement of cell density using absorbance at 665 nm. At 0 hours the mean cell density in the control was 18,500 cell/mL, increasing to 2,170,000 cells/mL after 72 hours. The corresponding values for the solvent control were 21,700 and 1,300,000 cell/mL, respectively. While the report did not detail the actual cell densities for the test media, the absorbance closely paralleled that of the controls (and solvent control). While the report did not detail the actual cell densities for the test media, the absorbance closely paralleled that of the controls (and solvent control), and consequently it was concluded that the BDP is not inhibitory to growth of algae up
to the limits of its water solubility.

Any other information on results incl. tables

It was concluded that the BDP is not inhibitory to growth of algae up to the limits of its water solubility.

Analysis of the solutions for the test compound after 72 hours indicated approximately 74% recovery (compared with a nominal initial concentration of 1 mg/L). This suggests that some of the test material had adsorbed to the surface of the algal cells.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

It was concluded that BDP is not inhibitory to growth of algae up to the limits of its water solubility.