Benzyl 4-hydroxybenzoate

Toxicity to aquatic algae and cyanobacteria

Description of key information

Toxicity to algae test was performed on Pseudokirchneriella subcapita algae (Aquatic toxicity and ecological risk assessment of seven parabens: Individual and additive approach, 2007) for 72 hrs with 5 different concentrations of benzylparaben according to OECD guideline 201.Algae was acclimatized at least 3 months and exposed to benzylparaben in flask and numbers of algae was measured by UV/visible spectrophotometer at 450 nm after calibration with known algal counts. Three replicates of blanks and concentrations were taken. After experiment it was observed that the EC50 value for benzylparaben (94-18-8) to Pseudokirchneriella subcapita was found to be 1.2 mg/l concentration.

Key value for chemical safety assessment

EC50 for freshwater algae:

1.2 mg/L

Additional information

Various studies were reviewed along with the prediction data to evaluate the effect of the test compound onaquatic algae and cyanobacteria. These are summarized as follows:

 

Toxicity to algae test was performed on Pseudokirchneriella subcapita algae (Aquatic toxicity and ecological risk assessment of seven parabens: Individual and additive approach, 2007) for 72 hrs with 5 different concentrations of benzylparaben according to OECD guideline 201.Algae was acclimatized at least 3 months and exposed to benzylparaben in flask and numbers of algae was measured by UV/visible spectrophotometer at 450 nm after calibration with known algal counts. Three replicates of blanks and concentrations were taken. After experiment it was observed that the EC50 value for benzylparaben (94-18-8) to Pseudokirchneriella subcapita was found to be 1.2 mg/l concentration.

From Aquatic toxicity and ecological risk assessment of seven parabens: Individual andadditive approach 2007, Long term toxicity test was performed on daphnia for 72 hrs. After experiment the end point for the long term toxicity to algae for benzylparaben (94-18-8) was found to be NOEC at 0.52 mg/l concentration.

The algal growth inhibition test (Preliminary ecological risk assessment of butylparaben and benzylparaben-1 Removal efficiency in wastewater treatment, acute/chronic toxicity for aquatic organisms, and effects on Medeka gene expression, 2007) was performed on Pseudokirchneriella subcapitata according to the OECD Guideline 201 for 96 hrs. Algae was purchased and acclimated for one month. This preincubated algal suspension were treated with 5 different concentrations at 100 ml flask in AAP medium at 24°C and controlled at 5,000 lux. Algal counts were measured by UV/Visible spectrophotometer at 450 nm.

From the experiment it was determined that the EC 50 and NOEC value for benzylparaben (94-18-8) of Pseudokirchneriella subcapitata was found to be 1.2 mg/l and 0.52 mg/l concentration.

 

From above mentioned supporting studies the target chemical benzylparaben (CAS No 94-18-8), the majority values are indicative that the chemical is likely to causeaquatic algae and cyanobacteria.