p-hydroxyphenylacetic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Gene mutation in vitro:

Ames test:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 4-Hydroxyphenylacetic Acid. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with S9 metabolic activation system. 4-Hydroxyphenylacetic Acid was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Based on the predicted result it can be concluded that the substance is considered to be not toxic as per the criteria mentioned in CLP regulation.

Genetic toxicity in vivo

Description of key information

In vivo micronucleus test was performed to determine the mutagenic nature of 4-Hydroxyphenylacetic Acid. The study was performed using Swiss Webster albino mice. The test chemical was dissolved in DMSO and used at dose level of 0 or 47 mg/Kg. 5 mice were used for each dose level. Concurrent solvent and positive control chemicals were also included in the study.Two doses (47 mg/Kg) of the test chemical, 24 h apart, were administered intraperitoneally to Swiss Webster albino mice. Six hours after the second administration, the mice were killed by dislocation of the neck. Both femora were removed by cutting through the pelvis and tibia. After removal of the muscle tissues, the distal epiphyseal portion was torn off. The proximal end of the femur was shortened carefully with scissors until a small opening to the marrow canal was seen. About 0.2 ml of fetal calf serum was introduced into a 1-ml syringe and then the hypodermic needle was inserted a few mm into the proximal end of the marrow. The femur was then submerged completely in 2 ml serum in a 5-ml test tube and the marrow was aspirated. After flushing and aspirating several times, the test tube was centrifuged at 1000 rpm for 5 rain and the supernatant was decanted. The cells in the sediment were mixed carefully using a Pasteur pipette and aspirator and were then smeared on glass slides. The 3 slides prepared for each mouse were left overnight to dry. The following procedure was used in staining the slides: 3 min in undiluted May-Grunwald stain; 2 rain in 50% May-Grunwald stain solution diluted with distilled water; and 10 rain in 15% aqueous Giemsa stain solution.The number of micronucleated polychromatic erythrocytes (MN-PCE) per 1000 polychromatic erythrocytes (PCE) was counted. 4-Hydroxyphenylacetic Acid did not induce micronuclei production in the femora of mice in vivo and hence it not likely to classify as a gene mutant in vivo.

Link to relevant study records

Reference

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed publication

Qualifier:

according to guideline

Guideline:

other: Refre below principle

Principles of method if other than guideline:

In vivo micronucleus test was performed to determine the mutagenic nature of 4-Hydroxyphenylacetic Acid

GLP compliance:

not specified

Type of assay:

other: In vivo micronucleus test

Specific details on test material used for the study:

- Name of test material: 4-Hydroxyphenylacetic Acid
- IUPAC name: 4-Hydroxyphenylacetic Acid
- Molecular formula: C8H8O3
- Molecular weight: 152.148 g/mol
- Substance type: Organic
- Physical state: No data
- Purity: No data
- Impurities (identity and concentrations): No data

Species:

mouse

Strain:

Swiss Webster

Remarks:

Albino

Details on species / strain selection:

No data

Sex:

not specified

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: No data
- Age at study initiation: 7-12 weeks old
- Weight at study initiation: No data
- Assigned to test groups randomly: [no/yes, under following basis: ] No data
- Fasting period before study: No data
- Housing: No data
- Diet (e.g. ad libitum): No data
- Water (e.g. ad libitum): No data
- Acclimation period: No data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%):No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data

IN-LIFE DATES: From: To: No data

Route of administration:

intraperitoneal

Vehicle:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The test chemical was soluble in DMSO
- Concentration of test material in vehicle: 8.0 mL/Kg
- Amount of vehicle (if gavage or dermal): 8.0 mL/Kg
- Type and concentration of dispersant aid (if powder): No data
- Lot/batch no. (if required): No data
- Purity: No data

Details on exposure:

No data

Duration of treatment / exposure:

48 hrs

Frequency of treatment:

Two doses, 24 h apart

Post exposure period:

No data

Remarks:

0 or 47 mg/Kg

No. of animals per sex per dose:

Total: 10
0 mg/Kg: 5 mice
47 mg/Kg: 5 mice

Control animals:

yes, concurrent vehicle

Positive control(s):

No data

Tissues and cell types examined:

Femoral tissue were examined

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: No data

TREATMENT AND SAMPLING TIMES ( in addition to information in specific fields): Two doses (47 mg/Kg) of the test chemical, 24 h apart, were administered intraperitoneally to Swiss Webster albino mice. Six hours after the second administration, the mice were killed by dislocation of the neck. Both femora were removed by cutting through the pelvis and tibia. After removal of the muscle tissues, the distal epiphyseal portion was torn off. The proximal end of the femur was shortened carefully with scissors until a small opening to the marrow canal was seen. About 0.2 ml of fetal calf serum was introduced into a 1-ml syringe and then the hypodermic needle was inserted a few mm into the proximal end of the marrow. The femur was then submerged completely in 2 ml serum in a 5-ml test tube and the marrow was aspirated. After flushing and aspirating several times, the test tube was centrifuged at 1000 rpm for 5 rain and the supernatant was decanted. The cells in the sediment were mixed carefully using a Pasteur pipette and aspirator and were then smeared on glass slides. The 3 slides prepared for each mouse were left overnight to dry.

DETAILS OF SLIDE PREPARATION: The following procedure was used in staining the slides: 3 min in undiluted May-Grunwald stain; 2 rain in 50% May-Grunwald stain solution diluted with distilled water; and 10 rain in 15% aqueous Giemsa stain solution.

METHOD OF ANALYSIS: No data

OTHER: No data

Evaluation criteria:

The number of micronucleated polychromatic erythrocytes (MN-PCE) per 1000 polychromatic erythrocytes (PCE) was counted

Statistics:

Mean ± SD

Sex:

not specified

Genotoxicity:

negative

Toxicity:

not specified

Vehicle controls validity:

valid

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

other: No mutagenic potential

Additional information on results:

No data

Table: Results of the micronucleus study

Compound	Dose (mg/Kg)	Number of MN-PCE/1000 PCE^a (mg/kg) (mean±SD)
4-Hydroxyphenylacetic Acid	47	3.53±0.81
DMSO	8.0 mL/Kg	2.52±0.62

 

Conclusions:

4-Hydroxyphenylacetic Acid did not induce micronuclei production in the femora of mice in vivo and hence it not likely to classify as a gene mutant in vivo.

Executive summary:

In vivo micronucleus test was performed to determine the mutagenic nature of 4-Hydroxyphenylacetic Acid. The study was performed using Swiss Webster albino mice. The test chemical was dissolved in DMSO and used at dose level of 0 or 47 mg/Kg. 5 mice were used for each dose level. Concurrent solvent and positive control chemicals were also included in the study.Two doses (47 mg/Kg) of the test chemical, 24 h apart, were administered intraperitoneally to Swiss Webster albino mice. Six hours after the second administration, the mice were killed by dislocation of the neck. Both femora were removed by cutting through the pelvis and tibia. After removal of the muscle tissues, the distal epiphyseal portion was torn off. The proximal end of the femur was shortened carefully with scissors until a small opening to the marrow canal was seen. About 0.2 ml of fetal calf serum was introduced into a 1-ml syringe and then the hypodermic needle was inserted a few mm into the proximal end of the marrow. The femur was then submerged completely in 2 ml serum in a 5-ml test tube and the marrow was aspirated. After flushing and aspirating several times, the test tube was centrifuged at 1000 rpm for 5 rain and the supernatant was decanted. The cells in the sediment were mixed carefully using a Pasteur pipette and aspirator and were then smeared on glass slides. The 3 slides prepared for each mouse were left overnight to dry. The following procedure was used in staining the slides: 3 min in undiluted May-Grunwald stain; 2 rain in 50% May-Grunwald stain solution diluted with distilled water; and 10 rain in 15% aqueous Giemsa stain solution.The number of micronucleated polychromatic erythrocytes (MN-PCE) per 1000 polychromatic erythrocytes (PCE) was counted. 4-Hydroxyphenylacetic Acid did not induce micronuclei production in the femora of mice in vivo and hence it not likely to classify as a gene mutant in vivo.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Gene mutation in vitro:

Prediction model based estimation for the target chemical and data from read across chemicals have been reviewed to determine the mutagenic nature of 4 -hydroxyphenylacetic acid. The studies are as mentioned below:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, gene mutation was predicted for 4-Hydroxyphenylacetic Acid. The study assumed the use of Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 with and without S9 metabolic activation system. 4-Hydroxyphenylacetic Acid was predicted to not induce gene mutation in Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102 in the presence and absence of S9 metabolic activation system and hence, according to the prediction made, it is not likely to classify as a gene mutant in vitro.

Gene mutation toxicity was predicted for 4-Hydroxyphenylacetic Acid using the battery approach from Danish QSAR database (2018). The study assumed the use of Salmonella typhimurium bacteria in the Ames test. The end point for gene mutation has been modeled in the Danish QSAR using the three software systems Leadscope, CASE Ultra and SciQSAR. Based on predictions from these three systems, a fourth and overall battery prediction is made. The battery prediction is made using the so called Battery algorithm. With the battery approach it is in many cases possible to reduce “noise” from the individual model estimates and thereby improve accuracy and/or broaden the applicability domain. Gene mutation toxicity study as predicted by Danish QSAR 4-Hydroxyphenylacetic Acid is negative and hence the chemical is predicted to not classify as a gene mutant in vitro.

The ability of4-Hydroxyphenylacetic Acid to induce chromosomal aberration was predicted using Chinese hamster ovary cells (CHO) using Danish QSAR database (2018). The end point for chromosome aberrations has been modeled in the Danish QSAR using the three software systems Leadscope, CASE Ultra and SciQSAR. Based on predictions from these three systems, a fourth and overall battery prediction is made. The battery prediction is made using the so called Battery algorithm. With the battery approach it is in many cases possible to reduce “noise” from the individual model estimates and thereby improve accuracy and/or broaden the applicability domain. 4-Hydroxyphenylacetic Acid does notinduce chromosome aberrations inChinese hamster ovary cells (CHO) and hence is predicted to not classify as a gene mutant in vitro.

The above mentioned predicted data is further supported by the data from read across chemicals as mentioned below:

Gene mutation toxicity study was performed by Rapson et al (Bulletin of Environmental Contamination and Toxicology, 1980) to determine the mutagenic nature of 70 -80% structurally similar read acrosschemical p-Hydroxybenzoic acid (RA CAS no 99 -96 -7). The study was performed as part of mutagenicity produced by aqueous chlorination of organic compounds at dose level of 0.1, 1, 10, 100 or 1000  µg/plate. p-Hydroxybenzoic acid did not induce reversion of mutant strains without chlorination and henceis not mutagenic in the bacteriumSalmonella typhimuriumTA 100 and hence is not likely to classify as gene mutant in vitro.

Ames Salmonella/ Microsome Reverse Mutation test was also performed to test the mutagenic activity of another 70 -80% structurally similar read across chemical 4 -methoxyphenylacetic acid (RA CAS no 104 -01 -8) in five Salmonella typhimurium tester strains with five concentrations ranging between 100-10000 µg/plate both in the presence and absence of S9 metabolic activation system. The doses were selected on the basis of dose range finding study to determine toxicity. The preliminary study was performed using Salmonella typhimurium strain TA100 in the presence and absence of S9 metabolic activation system. No toxicity was noted at the mentioned dose level. The main study was performed in triplicate with concurrent negative and positive controls by the plate incorporation protocol. No positive responses were noted in the preliminary and confirmatory mutagenicity studies. 4-methoxyphenylacetic acid (MPAA) did not exhibit mutagenecity in salmonella typhimurium strains under the test conditions with and without metabolic activation system and hence is not likely to classify as a gene mutant in vitro.

Gene mutation in vivo:

In vivo micronucleus test was performed by Villasenor et al (Mutation Research, 1989) to determine the mutagenic nature of 4-Hydroxyphenylacetic Acid. The study was performed using Swiss Webster albino mice. The test chemical was dissolved in DMSO and used at dose level of 0 or 47 mg/Kg. 5 mice were used for each dose level. Concurrent solvent and positive control chemicals were also included in the study.Two doses (47 mg/Kg) of the test chemical, 24 h apart, were administered intraperitoneally to Swiss Webster albino mice. Six hours after the second administration, the mice were killed by dislocation of the neck. Both femora were removed by cutting through the pelvis and tibia. After removal of the muscle tissues, the distal epiphyseal portion was torn off. The proximal end of the femur was shortened carefully with scissors until a small opening to the marrow canal was seen. About 0.2 ml of fetal calf serum was introduced into a 1-ml syringe and then the hypodermic needle was inserted a few mm into the proximal end of the marrow. The femur was then submerged completely in 2 ml serum in a 5-ml test tube and the marrow was aspirated. After flushing and aspirating several times, the test tube was centrifuged at 1000 rpm for 5 rain and the supernatant was decanted. The cells in the sediment were mixed carefully using a Pasteur pipette and aspirator and were then smeared on glass slides. The 3 slides prepared for each mouse were left overnight to dry. The following procedure was used in staining the slides: 3 min in undiluted May-Grunwald stain; 2 rain in 50% May-Grunwald stain solution diluted with distilled water; and 10 rain in 15% aqueous Giemsa stain solution.The number of micronucleated polychromatic erythrocytes (MN-PCE) per 1000 polychromatic erythrocytes (PCE) was counted. 4-Hydroxyphenylacetic Acid did not induce micronuclei production in the femora of mice in vivo and hence it not likely to classify as a gene mutant in vivo.

Based on the data available for the target chemical and its read across chemicals, 4 -hydroxybenzoic acid does not exhibit gene mutation in vitro and in vivo. Hence the test chemical is not likely to classify as a gene mutant in vitro and in vivo.

Justification for classification or non-classification

Based on the data available for the target chemical and its read across chemicals, 4 -hydroxybenzoic acid (CAS no 156 -38 -7) does not exhibit gene mutation in vitro and in vivo. Hence the test chemical is not likely to classify as a gene mutant in vitro and in vivo.