3-phenylpropionic acid

Endpoint summary

Description of key information

Biodegradation in water

Biodegradation study was conducted for evaluating the percentage biodegradability of test substance 3 -phenylpropanoic acid (CAS no. 501 -52 -0)(Enzyme and Microbial Technology, 1999).P. furiosuswas used as a test inoculum.P. furiosus(DSM 3638) was grown anaerobically at 90°C in a basic medium. Yeast extract, cysteine, vitamins, and trace elements were added. Potato starch (5 g/1) was used as a carbon and energy source. Cells were grown in 100 ml bottles containing 50 ml medium, which was flushed with N2/CO2 (80/20) before inoculation. During growth, the bottles were shaken continuously at 200 rev./min. The medium was inoculated with a 2% preculture. At the start of growth the pH was 6.8 - 7.0 and was not adjusted during the experiment. Growth was determined by the increase in protein concentration and by dihydrogen production. Protein concentration was measured using the Coomassie Brilliant Blue-method with bovine serum albumin as standard. Dihydrogen production was analyzed by gas chromatography with N2 as internal standard.All samples [30 ml for GC analysis, 1 ml for high-performance liquid chromatography (HPLC) analysis] were centrifuged for 15 min at 18,000g.In the case of aromatic compounds; the supernatant was directly analyzed by HPLC. Aliphatic compounds were analyzed by GC. Before this analysis, the pH of 25 ml supernatant was decreased to 2.5 with 5 N HC1, and 5 g NaCl was added to the supernatant. These samples were extracted with 2 ml di-ethylether containing 0.1% 1-pentanol as an internal standard. The ether phase was analyzed. All experiments were repeated three times.The percentage degradation of test substance was determined to be 69%by GC and HPLC parameter in 25 hrs.3-phenyl-l-propanol was formed as a metabolite during the degradation of test chemical3-phenylpropanoic acid byP. furiosus. Thus, based on percentage degradation, chemical 3-phenylpropanoic acid can be considered to be readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 3-phenylpropanoic acid (CAS No. 501 -52 -0). If released in to the environment, 22.1% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 3-phenylpropanoic acid in water is estimated to be 15 days (360 hrs). The half-life (15 days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of 3-phenylpropanoic acid in sediment is estimated to be 135 days (3240 hrs).  However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as 0.0893%), indicates that 3-phenylpropanoic acid is not persistent in sediment.

Biodegradation in soil

The half-life period of 3-phenylpropanoic acid (CAS No. 501 -52 -0) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 77.7% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 3 -phenylpropanoic acid in soil is estimated to be 30 days (720 hrs). Based on this half-life value of 3-phenylpropanoic acid, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low

Bioaccumulation: aquatic / sediment

From BCFBAF (v3.00) model of EPI suite and PBT profiler the estimated bio concentration factor (BCF) for 3-phenylpropanoic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 3-phenylpropanoic acid is not expected to bio accumulate in the aquatic environment.

Adsorption / desorption

The Soil Adsorption Coefficient i.e Koc value of 3-phenylpropanoic acid was estimated using EPI suite  KOCWIN model (v2.00) as Koc 53.88 L/kg(log Koc=1.73)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 3-phenylpropanoic acid has a Low sorption to soil and sediment and therefore have rapid to moderate migration potential to groundwater.

Additional information

Biodegradation in water

Various study for the target compound 3-phenylpropanoic acid (CAS No. 501-52-0) and the study for its read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In an experimental key study from peer reviewed journal (Enzyme and Microbial Technology, 1999), biodegradation experiment was conducted for evaluating the percentage biodegradability of test substance 3 -phenylpropanoic acid (CAS no. 501 -52 -0). P. furiosus was used as a test inoculum. P. furiosus (DSM 3638) was grown anaerobically at 90°C in a basic medium. Yeast extract, cysteine, vitamins, and trace elements were added. Potato starch (5 g/1) was used as a carbon and energy source. Cells were grown in 100 ml bottles containing 50 ml medium, which was flushed with N2/CO2 (80/20) before inoculation. During growth, the bottles were shaken continuously at 200 rev./min. The medium was inoculated with a 2% preculture. At the start of growth the pH was 6.8 - 7.0 and was not adjusted during the experiment. Growth was determined by the increase in protein concentration and by dihydrogen production. Protein concentration was measured using the Coomassie Brilliant Blue-method with bovine serum albumin as standard. Dihydrogen production was analyzed by gas chromatography with N2 as internal standard. All samples [30 ml for GC analysis, 1 ml for high-performance liquid chromatography (HPLC) analysis] were centrifuged for 15 min at 18,000g.In the case of aromatic compounds; the supernatant was directly analyzed by HPLC. Aliphatic compounds were analyzed by GC. Before this analysis, the pH of 25 ml supernatant was decreased to 2.5 with 5 N HC1, and 5 g NaCl was added to the supernatant. These samples were extracted with 2 ml di-ethylether containing 0.1% 1-pentanol as an internal standard. The ether phase was analyzed. All experiments were repeated three times. The percentage degradation of test substance was determined to be 69%by GC and HPLC parameter in 25 hrs.3-phenyl-l-propanol was formed as a metabolite during the degradation of test chemical3-phenylpropanoic acid by P. furiosus. Thus, based on percentage degradation, chemical 3-phenylpropanoic acid can be considered to be readily biodegradable in nature.

 

In a supporting data, biodegradation study was conducted for evaluating the percentage biodegradability of test substance 3-phenylpropanoic acid (CAS no. 501-52-0) (D. M. WEBLEY et. al; 1955). Nocardia opaca (Bacterium) was used as a test inoculum. Organisms were grown on liquid medium, but the shaking machine was used. Medium containing 2% (w/v) glucose was used in 200 ml. lots in 1 1. Pyrex culture flasks. Incubation was at 25°C for 4-6 days. For the detection of intermediates, experiment was performed on the shaking machine used for the production of the cells. The same type of flask was employed containing 100ml of 0.0133M-phosphate (pH7.2), 5 -25µmole/ml. phenyl substituted acid (as sodium salt) and 200 -400mg (dry weight) of washed glucose-grown cells. Strict aseptic conditions were observed as the experiments were sometimes continued over a number of days. Samples were withdrawn periodically when required, centrifuged and examined spectrochemically. Chromatographic analyses were performed when desirable during the course or at the end of the experiment when the whole contents of the flasks were used. Samples were periodically removed, with aseptic precautions, centrifuged arid examined spectrochemically. Successive absorptionietric analyses of the phenylpropionic acid solution at intervals over the complete experiment shows that the benzoic acid concentration rises steadily until the substrate is exhausted, and the conversion is approximately quantitative; the concentration of cinnamic acid rises to a maximum and then falls to zero at the end of the experiment. It is clear, therefore, that cinnamic acid is an intermediate in the oxidation of phenylpropionic acid to benzoic acid by Nocardiaopaca. The formation of benzoic acid from phenylpropionic acid was finally confirmed by its isolation at the end of the experiment. Thus, based on this, it can be concluded that the chemical 3-phenylpropanoic acid is considered to be biodegradable in nature.

 

In a supporting biodegradation study from authoritative database (J-CHECK, 2016) for the read across chemical Benzoic acid (CAS no. 65-85-0),biodegradation experiment was conducted for 14 days for evaluating the percentage biodegradability of read across substance Benzoic acid. Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of read across substance was determined to 85%, 98% and 100% by BOD, TOC removal and UV-Vis parameter in 28 days. Thus, based on percentage degradation, Benzoic acid is considered to be readily biodegradable in nature.

 

Another biodegradation study for the same read across chemical Benzoic acid(CAS no. 65-85-0)was conducted for 28 days for evaluating the percentage biodegradability of read across substance Benzoic acid (The Science of the Total Environment, Vol. 170, Pg. no. 43-51, 1995). Seeding bacteria was used as a test inoculum. The seeding bacteria had been cultured in a continuous anaerobic bioreactor at 37 + 1°C.Synthetic sewage, composed of glucose, peptone and corn steap liquor (carbon ratio = 1:1:2), is supplied into the reactor (3.0 g-C/l, 8.0 g-CS./.d). In this culture, > 95% acidic decomposition and > 90% methanogenic decomposition are achieved.

A standard test using 50 ml vials (total capacity: 68 ml) was employed. Ten test vials were prepared under the same conditions, and they were set in a water bath at 37°C ± 0.5”C. The original solution was added to the test inoculum and organic medium in oxygen-free water. At the starting time and after every week, two vials were opened simultaneously, and the concentration of organic compound was analyzed. The concentration of organic compound was determined by dissolved organic carbon (DOC).Biodegradation ratio is determined by analysing the decrease of DOC in the standard test. The percentage degradation of the read across compound was determined to be 101% in 14 days by using standard test Thus, based on the percentage degradation, the read across chemical Benzoic acid was considered to be readily biodegradable in nature.

 

For the read across chemical Benzoic acid (CAS no. 65-85-0), biodegradation study was conducted (The Science of the Total Environment, Vol. 170, Pg. no. 31-41, 1995) for 28 days for evaluating the percentage biodegradability of read across substance Benzoic acid (CAS no. 65-85-0) by anaerobic bacteria as a test inoculum. Anaerobic bacteria was used as a test inoculum. The cultivated bacteria was prepared for seeding as follows. The bacteria suspension was drowned, homogenized, and separated with a centrifuge at 3000 rev./min for 10 min. The deposit was washed by the basal medium solution and separated again with a centrifuge. The deposit was dissolved again in the basal medium solution and its concentration was determined. This original suspension of bacteria was seeded in the test vials and its concentration was reconfirmed. The seeding bacteria had been cultured by a synthetic sewage in a continuous bioreactor at 37 + 1°C. 100 and 30 mg/l conc. was used for both inoculum and test substance conc., respectively.

The test involve the use of 50 ml vials (total capacity: 68 ml). Ten test vials were prepared under the same conditions, and they were set in a water bath at 37°C ± 0.5”C. The original solution was added to the test inoculum and basal medium solution, which was prepared by organic medium and/or inorganic medium in oxygen-free water. At the starting time and after every week, two vials were opened simultaneously, and the concentration of organic compound was analyzed. The concentration of organic compound was determined by dissolved organic carbon (DOC) or chromatography. Biodegradation ratio is determined by analyzisng the decrease of DOC. The percentage degradation of the read across compound was determined to be 82% by DOC removal parameter in 14 days. Thus, based on the percentage degradation, the read across chemical Benzoic acid is considered to be readily biodegradable in nature.

 

On the basis of above results for target chemical 3 -phenylpropanoic acid (from peer reviewed journals) and for its read across substance (from authoritative database J-CHECK, 2016 and peer reviewed journals), it can be concluded that the test substance 3-phenylpropanoic acid can be expected to be readily biodegradable in nature.

Biodegradation in water and sediment

Estimation Programs Interface (EPI Suite, 2017) prediction model was run to predict the half-life in water and sediment for the test compound 3-phenylpropanoic acid (CAS No. 501 -52 -0). If released in to the environment, 22.1% of the chemical will partition into water according to the Mackay fugacity model level III and the half-life period of 3-phenylpropanoic acid in water is estimated to be 15 days (360 hrs). The half-life (15 days estimated by EPI suite) indicates that the chemical is not persistent in water and the exposure risk to aquatic animals is moderate to low whereas the half-life period of 3-phenylpropanoic acid in sediment is estimated to be 135 days (3240 hrs).  However, as the percentage release of test chemical into the sediment is less than 1% (i.e, reported as 0.0893%), indicates that 3-phenylpropanoic acid is not persistent in sediment.

Biodegradation in soil

The half-life period of 3-phenylpropanoic acid (CAS No. 501 -52 -0) in soil was estimated using Level III Fugacity Model by EPI Suite version 4.1 estimation database (EPI suite, 2017). If released into the environment, 77.7% of the chemical will partition into soil according to the Mackay fugacity model level III. The half-life period of 3 -phenylpropanoic acid in soil is estimated to be 30 days (720 hrs). Based on this half-life value of 3-phenylpropanoic acid, it is concluded that the chemical is not persistent in the soil environment and the exposure risk to soil dwelling animals is moderate to low

On the basis of available information, the test substance 3 -phenylpropanoic acid can be considered to be readily biodegradable in nature.

 

Bioaccumulation: aquatic / sediment

Three studies including all predicted data from validated models for bioaccumulation (BCF) endpoint of target chemical 3-phenylpropanoic acid (Cas no. 501-52-0) were summarized as follows:

 

First study from prediction done using BCFBAF (v3.00) model and PBT profiler which indicate the estimated bio concentration factor (BCF) for 3-phenylpropanoic acid is 3.2 L/kg wet-wt which does not exceed the bioconcentration threshold of 2000.Thus it is concluded that 3-phenylpropanoic acid is not expected to bio accumulate in the aquatic environment.

 Above prediction supported by data Scifinder database which suggest the Bioconcentration factor (BCF) for target chemical 3-phenylpropanoic acid was predicted to be 4.05 at pH 1,4.04 at pH 2, 3.96 at pH 3, 3.31 at pH 4, 1.26 at pH 5, 1 at pH range 6-10 and temperature 25 deg.C.Based on the BCF concentration at all range of pH it is concluded that the test chemical 3-phenylpropanoic acid is non bioaccumulative in nature as it does not exceed the BCF criteria of 2000. 

Last study from Chemspider - ACD/PhysChem Suite prediction model indicate the Bioconcentration factor (BCF) for target chemical 3-phenylpropanoic acid was estimated to be 2.38 at pH 5.5 and 1 at pH 7.4 at temperature 25 deg.C.

Thus all available studies for bioaccumulation endpoint concluded that the test substance 3-phenylpropanoic acid (Cas no. 501-52-0) is expected to be non Bioaccumulative in aquatic environment.

Adsorption / desorption

Four studies including predicted data and experimental studies for adsorption (KOC) endpoint of target chemical 3-phenylpropanoic acid (Cas no. 501-52-0) with relevant read across which is structurally similar to target were summarized as follows:

 

First study from prediction done using KOCWIN model (v2.00) of EPI suite indicate the Soil Adsorption Coefficient i.e Koc value of 3-phenylpropanoic acid was estimated as Koc 53.88 L/kg(log Koc=1.73)  by means of MCI method at 25 deg.C. This Koc value indicates that the substance 3-phenylpropanoic acid has a Low sorption to soil and sediment and therefore have rapid to moderate migration potential to groundwater.

And study from Scifinder database suggest the soil adsorption coefficient i.e Koc value of test substance 3-phenylpropanoic acid was estimated to be 94.7 (Log koc-1.976) at pH 1, 94.5 (Log koc-1.97) at pH 2, 92.7 (Log koc-1.96 at pH 3, 77.5 (Log koc-1.88) at pH 4, 29.4  (Log koc-1.468) at pH 5, 4.09 (Log koc-0.611) at pH 6 and 1 (Log koc-0) at pH 7  -10 and temperature 25 deg.C.This Koc value at all range of pH condition indicates that the substance 3-phenylpropanoic acid has negligible to low sorption to soil and sediment and therefore have rapid migration potential to groundwater.

Whereas result from Chemspider - ACD/PhysChem Suite indicate the soil adsorption coefficient i.e Koc value of test substance 3-phenylpropanoic acid was estimated to be 35.85 (log koc: 1.55) at pH 5.5 and  temp.25 deg.C this Koc value indicates that the substance 3-phenylpropanoic acid has negligible sorption to soil and sediment and therefore have rapid migration potential to groundwater.

Above all prediction results for target chemical supported by experimental data of read across Benzyl butyrate(CAS No.103-37-7) which suggest The adsorption coefficient Koc in soil and in sewage sludge Benzyl butyrate(CAS No. 103-37-7)was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to estimated Kocrange of the test substance and generalized calibration graph was prepared. The reference substances were4-chloroaniline, 4-methylaniline, N methylaniline, 2-Nitrophenol, Nitrobenzene, 4-Nitrobenzamide, N,N-dimethylbenzamide, N-methylbenzamide, Benzamide, phenanthrene having Koc value ranging from 1.239 to 4.09.The Log Kocvalue was found tobe3.323± 0.0005at 25°C.(UERL laboratory;2017)

Thus all available studies for adsorption endpoint concluded that the test substance 3-phenylpropanoic acid (Cas no. 501-52-0) is expected to have high mobility in soil and sediment compartment.