Benzyl 4-hydroxybenzoate

Endpoint summary

Description of key information

Short-term toxicity to fish:

Study was conducted to access the effect of test chemical Benzyl 4-Hydroxybenzoate on the growth of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). The test substance was sparingly soluble in water. Therefore, the stock solution was prepared by dissolving 2 gm of the test substance in 2 liter of potable water (passed through reverse osmosis system) with continuous stirring of 72 hrs. After the completion of 72 hrs stirring, the stock sample was analytically detected to calculate the actual solubility and the solubility obtained was then used for achieving test concentrations of 0.625 mg/L,1.25 mg/L,2.5 mg/L,5 mg/L & 10 mg/L, respectively. Bowl aquaria containing 2 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. The nominal concentration selected for the experiment was 0.625mg/L, 1.25mg/L, 2.5mg/L, 5mg/L, 10mg/L and Zebra fish were exposed to this concentration for 96 hours. The lethal concentrations LC50 was observed to be in the range of > 2.5 mg/l to < 5 mg/l. Based on nominal concentrations, experimental median lethal Concentrations [LC-50 (96 h)] for test chemical Benzyl 4-Hydroxybenzoate on Zebra Fish Danio rerio was determine to be > 2.5 mg/l to < 5 mg/l. Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified as aq aquatic chronic 2 as per the CLP classification criteria.

Long-term toxicity to fish:

Long term toxicity to fish was performed for 7 days at five different concentrations ranges from 1.0 to 25 mg/L. Four replicates of 10 P. promelas in 250 ml of test solution for each concentration were prepared and renewed daily. Fish were fed twice daily and mortality was observed daily. After 7 d of exposure, average weight per fish was calculated and compared to the control. So, on the basis of above result the endpoint for benzylparaben (94-18-8) long term toxicity to P. promelas was found to be LOEC at 1.7 mg/L concentration.

Short-term toxicity to aquatic invertebrates:

Short term toxicity test was performed on daphnia magna for 48 hrs. Five concentrations of benzylparaben were used in 50 ml beaker and 5 daphnids were kept in per vessel under specific environmental conditions. 48 hrs observation period and immobilization of daphnia was observed.After experiment it was observed that the EC50 value of benzylparaben (94-18-8) for Daphnia magna was found to be 2.1 mg/l concentration.

Long-term toxicity to aquatic invertebrates :

The long term toxicity test was performed on Daphnia magna for 21 days according to the OECD guideline 211. 20 ml test tubes were used as a vessel with different concentrations in which 1 larva at each test tubes were kept for experiment. After 48 hrs test water were replaced and count the cumulative numbers of broods. Based on that both Immobilized bodies and cumulative numbers of broods NOEC was determined. On the basis of above experiment the NOEC value for benzylparaben (94-18-8) to Daphnia magna was found to be 0.84 mg/l concentration.

 

Toxicity to aquatic algae and cyanobacteria:

Aim of this study was to evaluate the nature of chemical test chemical when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The stock solution 50 g/l was prepared by dissolving white powder in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium. Test solutions were kept in ultrasonic bath for 20 min and then inoculated by algae. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determine after an exposure period of 72 hrs. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical benzyl 4-hydroxybenzoate the ErC50 was determine to be 5.5 mg/l. Thus the ErC50 value, indicates that the substance is likely to be hazardous to aquatic algae and can be classified as aquatic chronic 2 category as per the CLP classification criteria.

 

Toxicity to microorganisms

Toxicity to micro-organisms study (Acute toxicity of parabens and their chlorinated by-products with Daphnia magna and Vibrio fischeri bioassays. 2009) was conducted onVibrio fischeri.The study was carried out using the test conditions and the operating protocol of theV. fischeriacute toxicity test (Environmental Protection Series, 1992). Test chemicals was of special-grade reagent and was used without purification.  The test bacteria was exposed to the test substancebenzylparabenwith exposure duration of 5 and 15 mins.Luminescence was measured with a Microtox luminometer (Model 500; Microbics Corp., Carlsbad, CA, USA) in the acute mode. The toxic effect values reflect the ratio of the decrease in bacterial light production to the remaining light. The Microtox statistical software, version 7, was used to calculate the toxic effect values for each sample dilution and the sample concentration inducing 50% light inhibition (EC50) for each log–log dose–response curve and their corresponding confidence limits. The toxicity was expressed in terms of effective concentration values and toxicity units (TUs). The TU value was calculated using EC50 (TU = 100 EC50−1).  The logarithms of then-octanol–water partition coefficients (logP) of the test compound was also determined using an HPLC method according to the OECD guideline. Based ondecrease in bacterial light production by the test organism V. fischeri, the EC50 value was found to be 0.0038 mg/l.

Additional information

Short-term toxicity to fish:

Summarized result for the toxicity of test chemical benzyl 4-hydroxybenzoate (94 -18 -8) on the growth of fish are as follows:

In the first key study from experimental data 2017 toxicity was measured. Study was conducted to access the effect of test chemical Benzyl 4-Hydroxybenzoate on the growth of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). The test substance was sparingly soluble in water. Therefore, the stock solution was prepared by dissolving 2 gm of the test substance in 2 liter of potable water (passed through reverse osmosis system) with continuous stirring of 72 hrs. After the completion of 72 hrs stirring, the stock sample was analytically detected to calculate the actual solubility and the solubility obtained was then used for achieving test concentrations of 0.625 mg/L,1.25 mg/L,2.5 mg/L,5 mg/L & 10 mg/L, respectively. Bowl aquaria containing 2 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. The nominal concentration selected for the experiment was 0.625mg/L, 1.25mg/L, 2.5mg/L, 5mg/L, 10mg/L and Zebra fish were exposed to this concentration for 96 hours. The lethal concentrations LC50 was observed to be in the range of > 2.5 mg/l to < 5 mg/l. Based on nominal concentrations, experimental median lethal Concentrations [LC-50 (96 h)] for test chemical Benzyl 4-Hydroxybenzoate on Zebra Fish Danio rerio was determine to be > 2.5 mg/l to < 5 mg/l. Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified as aq aquatic chronic 2 as per the CLP classification criteria.

Similarly in 2nd study short-term toxicity to Pimephales promelas was performed for 48 hrs at five nominal concentrations in a temperature-controlled incubator at 24°C with a 16:8 light: dark cycle.500 ml beaker was taken having 250 ml of test chemical. Test solution was prepared by dissolved in high-performance liquid chromatography grade acetone and delivered into RHW at 0.1% acetone. No aeration was used and LD 50 value was determined at 24 and 48 hrs.

On the basis of above experiment result the LD 50 value for Pimephales promelas for benzylparaben (94-18-8) was determine to be 3.3 mg/L concentration.

Above studies supported by the third study from peer reviewed journal. Acute toxicity test was performed on fish for 96 hrs at 5 different concentrations according to the OECD guideline 203.10 fishes of 10 days old were used in 100 ml beaker. Half of the paraben solution was replaced every 24 h. Specific environmental condition was maintained and LC 50 value was determined.After experiment it was observed that the LC 50 value for benzylparaben(94-18-8) to fish was found to be 0.73mg/l concentrations.

As maximum studies supports the classification in category 2, thus on that basis chemical concluded to be classified as aquatic chronic 2 as per CLP.

 

Long-term toxicity to fish:

Various studies were reviewed along with the prediction data to evaluate the effect of the test compound on long term toxicity to fish. These are summarized as follows:

Long term toxicity to fish was performed for 7 days at five different concentrations ranges from 1.0 to 25 mg/L. Four replicates of 10 P. promelas in 250 ml of test solution for each concentration were prepared and renewed daily. Fish were fed twice daily and mortality was observed daily. After 7 d of exposure, average weight per fish was calculated and compared to the control. So, on the basis of above result the endpoint for benzylparaben (94-18-8) long term toxicity to P. promelas was found to be LOEC at 1.7 mg/L concentration.

Long term toxicity test was performed on fish for 14 days by the method Medaka vitellogenin test. After test it was found that the end point for the long term toxicity to fish for benzylparaben (94-18-8) was found to be 0.02 mg/l concentration.

Long term toxicity test was performed on fish for 7 days by the method Medaka vitellogenin test. After test it was found that the end point for the long term toxicity to fish for benzyl paraben (94-18-8) was found to be LOEC at 1.7mg/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 not likely to cause aquatic fish toxicity.

 

Short-term toxicity to aquatic invertebrates:

Various studies were reviewed along with the prediction data to evaluate the effect of the test compound on Short-term toxicity to aquatic invertebrates. These are summarized as follows:

Short term toxicity test was performed on daphnia magna for 48 hrs. Five concentrations of benzylparaben were used in 50 ml beaker and 5 daphnids were kept in per vessel under specific environmental conditions. 48 hrs observation period and immobilization of daphnia was observed.After experiment it was observed that the EC50 value of benzylparaben (94-18-8) for Daphnia magna was found to be 2.1 mg/l concentration.

From probabilistic ecological hazard assessment of parabens using daphnia magna and pimephales promelas publication, Short-term toxicity to daphnia magna was performed for 48 hrs at five nominal concentrations in a temperature-controlled incubator at 24°C with a 16:8 light: dark cycle.100 ml beaker was taken having 80 ml of test chemical. Test solution was prepared by dissolved in high-performance liquid chromatography grade acetone and delivered into RHW at 0.1% acetone. No aeration was used and LD 50 value was determined at 24 and 48 hrs.

On the basis of above experiment result the LD 50 value for Daphnia magna for benzylparaben (94-18-8) was found to be 4.0 mg/L concentration.

From Aquatic toxicity and ecological risk assessment of seven parabens: Individual andadditive approach journals, the short term toxicity test was performed on daphnia magna for 48 hrs. Five concentrations of benzylparaben were used in 50 ml beaker and 5 daphnids were kept in per vessel under specific environmental conditions. 48 hrs observation period and immobilization of daphnia was observed.After experiment it was observed that the EC50 value of benzylparaben (94-18-8) for Daphnia magna was found to be 2100 µg/l concentration.

Short term toxicity test(Masanori Terasaki, Masakazu Makino and Norihisa Tatarazako, 20009)was performed on daphnia magna for 48 hrs. Five concentrations of benzylparaben were used in 50 ml beaker and 5 daphnids were kept in per vessel under specific environmental conditions. 48 hrs observation period and immobilization of daphnia was observed.After experiment it was observed that the EC50 value of benzylparaben (94-18-8) for Daphnia magna was found to be 2100 µg/l concentration.

Short term toxicity study to Daphnia magna (Chapter 14 - Hydroxy Benzoate Preservatives (Parabens) in the Environment: Data for Environmental Toxicity Assessment, 2009) was carried out for 48 hrs. Daphtoxkit bioassay test was performed for the toxicity study. Study was performed in accordance with test procedures prescribed by national and international organizations OECD 202, ISO 6341, EEC, USEPA, ASTM.

All stock solutions were prepared in methanol and serially diluted in distilled water to obtain the target concentrations. The methanol concentration in the exposure solutions, including controls, was 0.01% (v/v) in distillate water in the tested solutions. Potassium dichromate (K2Cr2O7) was used as a control substance. The test bacteria was exposed to the test substancebenzyl parabenwith exposure duration of 24 and 48 hrs. The number of immobilized daphnia was recorded after exposure for 24 and 48 hrs. Based on immobilization of test organism, the EC50 value at 24 and 48 hrs was found to be5.2 and 6.0 mg/l, respectively and LOEC value was found to be 1.2 mg/l.

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 cause aquatic invertebrates toxicity.

 

Long-term toxicity to aquatic invertebrates :

Various studies were reviewed along with the prediction data to evaluate the effect of the test compound on long-term toxicity to aquatic invertebrates. These are summarized as follows:  

The long term toxicity 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 Daphnia magna for 21 days according to the OECD guideline 211. 20 ml test tubes were used as a vessel with different concentrations in which 1 larva at each test tubes were kept for experiment. After 48 hrs test water were replaced and count the cumulative numbers of broods. Based on that both Immobilized bodies and cumulative numbers of broods NOEC was determined.On the basis of above experiment the NOEC value for benzylparaben (94-18-8) to Daphnia magna was found to be 0.84 mg/l concentration.

Long term toxicity (probabilistic ecological hazard assessment of parabens using daphnia magna and pimephales promelas, 2009) to Daphnia Magna was studied for 10 days at different concentrations. Neonates were used and Half of the LC50 determined from the acute test was used as the highest subchronic exposure concentration; a 0.5 dilution factor was then applied to prepare the remaining concentrations.

10 replicates with one Daphnia was applied to each concentration were fed during study. Daily observed for mortality and number of neonates.

So, on the basis of above result the endpoint for benzylparaben (94-18-8) long term toxicity to Daphnia Magna was found to be LOEC at 2 mg/L and 0.1 mg/l concentrations based on reproduction and growth.

 

From Aquatic toxicity and ecological risk assessment of seven parabens: Individual and additive approach, 2011. Long term toxicity test was performed on daphnia for 21 days. After experiment the end point for the long term toxicity to aquatic invertebrates for benzylparaben (94-18-8) was found to be NOEC at 0.84 mg/l concentration.

From Hiroshi Yamamoto, Ikumi Tamura, Yoshiko Hirata, Jun Kato, Keiichiro Kagota , Shota Katsuki ,Atsushi Yamamoto, Yoshihiro Kagami, Norihisa Tatarazako, 2011, The Long term toxicity test was performed on daphnia for 10 days. After experiment the end point for the long term toxicity to aquatic invertebrates for benzylparaben (94-18-8) was found to be LOEC at 0.1 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 invertebratestoxicity.

 

Toxicity to aquatic algae and cyanobacteria

Summarized result for the toxicity of test chemical benzyl 4-hydroxybenzoate (94 -18 -8) on the growth of aquatic algae are as follows:

In the first key study from experimental data 2017 toxicity was measured. Aim of this study was to evaluate the nature of chemical test chemical when comes in contact with the test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). Test was conducted according to the OECD guideline 201. The stock solution 50 g/l was prepared by dissolving white powder in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample with OECD growth medium. Test solutions were kept in ultrasonic bath for 20 min and then inoculated by algae. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determine after an exposure period of 72 hrs. Based on the growth rate inhibition of algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the exposure of chemical benzyl 4-hydroxybenzoate the ErC50 was determine to be 5.5 mg/l. Thus the ErC50 value, indicates that the substance is likely to be hazardous to aquatic algae and can be classified as aquatic chronic 2 category as per the CLP classification criteria.

First key study was supported by the second from peer reviewed journal 2011. Toxicity to algae test was performed on Pseudokirchneriella subcapita algae 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 to Pseudokirchneriella subcapita was observed to be 1.2 mg/l concentration.

Similar study was conducted to evaluate the effect of test chemical on the growth of aquatic algae and cyanobacteria. Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) exposed for 72 hrs with the test chemical. After the exposure of test chemical for 72 hrs, no effect were observed (NOEC) at 0.52 mg/l.

Based on the above result chemical was consider as toxic and classified as aquatic chronic 2 as per the CLP classification criteria.

 

Toxicity to microorganisms

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

Toxicity to micro-organisms study (Acute toxicity of parabens and their chlorinated by-products with Daphnia magna and Vibrio fischeri bioassays. 2009) was conducted onVibrio fischeri.The study was carried out using the test conditions and the operating protocol of theV. fischeriacute toxicity test (Environmental Protection Series, 1992). Test chemicals was of special-grade reagent and was used without purification. The test bacteria was exposed to the test substancebenzylparabenwith exposure duration of 5 and 15 mins.Luminescence was measured with a Microtox luminometer (Model 500; Microbics Corp., Carlsbad, CA, USA) in the acute mode. The toxic effect values reflect the ratio of the decrease in bacterial light production to the remaining light. The Microtox statistical software, version 7, was used to calculate the toxic effect values for each sample dilution and the sample concentration inducing 50% light inhibition (EC50) for each log–log dose–response curve and their corresponding confidence limits. The toxicity was expressed in terms of effective concentration values and toxicity units (TUs). The TU value was calculated using EC50 (TU = 100 EC50⁻¹). The logarithms of then-octanol–water partition coefficients (logP) of the test compound was also determined using an HPLC method according to the OECD guideline. Based ondecrease in bacterial light production by the test organismV. fischeri,the EC50 value was found to be 0.0038 mg/l.

 

Toxicity to micro-organisms study (Chapter 14 - Hydroxy Benzoate Preservatives (Parabens) in the Environment: Data for Environmental Toxicity Assessment, 2009) was conducted onVibrio fischerifor 30 mins. Microtox bioassay test was performed for the toxicity study. All stock solutions were prepared in methanol and serially diluted in distilled water to obtain the target concentrations. The methanol concentration in the exposure solutions, including controls, was 0.01% (v/v) in distillate water in the tested solutions. 2-4-dichlorophenol (DCP) was used as control solution. The test bacteria was exposed to the test substancebenzylparabenwith exposure duration of 15 and 30 mins.Bacterial luminescence inhibition was measured after 15 and 30 mins of exposure to tested solutions. Based ondecrease in bacterial light production by the test organismV. fischeri,the EC50 value after 15 and 30 exposure duration was found to be 0.11 mg/land LOEC value was found to be 0.02 mg/l.

Toxicity to micro-organisms study was conducted onPhotobacterium leiognathi SB strainfor 30 mins. Toxscreen bioassay test was performed for the toxicity study. All stock solutions were prepared in methanol and serially diluted in distilled water to obtain the target concentrations. The methanol concentration in the exposure solutions, including controls, was 0.01% (v/v) in distillate water in the tested solutions. 2-4-dichlorophenol (DCP) was used as control solution. The test bacteria was exposed to the test substancebenzylparabenwith exposure duration of 15 and 30 mins. Bacterial luminescence inhibition was measured after 15 and 30 mins of exposure to tested solutions. Based on decrease in bacterial light production by the test organismPhotobacterium leiognathi SB strain,the EC50 value after 15 and 30 exposure duration was found to be 1.3 and 1.6 mg/l, respectively and LOEC value was found to be 0.25 mg/l.

Toxicity to micro-organisms study was conducted onTetrahymena thermophilafor 28 hrs. Protoxkit bioassay test was performed for the toxicity study. All stock solutions were prepared in methanol and serially diluted in distilled water to obtain the target concentrations. The methanol concentration in the exposure solutions, including controls, was 0.01% (v/v) in distillate water in the tested solutions. Potassium dichromate (K2Cr2O7) was used as control substance. The test organism was exposed to the test substancebenzylparabenwith exposure duration 28 hrs. Inhibition in bacterial growth was measured after 24 and 28 hrs of exposure to tested solutions. Based on growth inhibition of test organismTetrahymena thermophila,the EC50 value after 24 and 28 hrs was found to be 4.3 and 5.7 mg/l, respectively and LOEC value was found to be 0.48 mg/l. 

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 cause aquatic microorganisms.

Based on the above studies chemical concluded to be toxic and classified as aquatic chronic 2 as per the CLP classification criteria.