Registration Dossier

Classification & Labelling & PBT assessment

PBT assessment

Currently viewing:

Administrative data

PBT assessment: overall result

PBT status:
the substance is not PBT / vPvB
Justification:

Classification of 4-methoxyphenylacetone for effects in the environment:

 

The chemical 4-methoxyphenylacetone (CAS no. 122-84-9) is usedas a flavouring agent in foods and as a fragrances indecorative cosmetics, fine fragrances etc.The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for 4-methoxyphenylacetone. The PBT criterion was herein assessed based on experimental data in conjunction with standardized environmental fate models. Here follows a description of the PBT assessment.

 

Persistence assessment

The tested substance does not fulfil the P criterion within Annex XIII based on the assessment that here follows:

 

Biotic degradation

Biodegradation experiment was performed for chemical 4-methoxyphenylacetone by using Beauveria bassiana (ATCC 7 159) fungus as inoculums for 3 days. 5 ml of T1 medium were seeded with microorganism and incubated for 4 days at 30°C. The biomass was suspended in 4 ml of T3 medium & 2 ml of this suspension was inoculated in 50 ml of the same medium & shaken at 180 rpm for 24 h at 30°C. 5 ml of this culture was inoculated in 50 ml of fresh T3 medium and incubated for 3 days in the same conditions. At this point 50 mg of solid substrates 4-methoxyphenylacetone was added & the mixture stirred at 180 rpm for 72 h at 30°C. 4-methoxyphenylacetone undergoes 28% degradation by considering degradative oxidation as parameter in 3 days. On the basis of %degradability value it can be concluded that 4-methoxyphenylacetone is readily biodegradable.

 

In a biodegradation study, percent conversion of test chemical was determined by using bacteria brevibacterium linens as inoculums. This bacterium was grown in laboratory at 30oC for 48 hrs. Then for conversion of 4-methoxyphenylacetone 3.284 mg/L conc. of test substrate was added to medium and incubated at 30°C for 48 h. After incubation 4-methoxyphenylacetone & conversion product (S)-(+)-4-methoxyamphetamine was analysed by HPLC. 4-methoxyphenylacetone undergoes 94 % conversion by considering test material analysis as parameter and brevibacterium linens IFO 12141 as inoculums in 2 days. On the basis of %conversion value it can be concluded that 4-methoxyphenylacetone is readily biodegradable.

 

In a prediction done using OECD QSAR tool box v3.3, Percent degradation of 4-methoxyphenylacetone was estimated as 85.22% by using BOD as parameter & microorganisms as inoculum in 28 days.  On the basis of %degradadability value, it can be concluded that 4-methoxyphenylacetone is readily biodegradable.

 

Experimental results from the read across substance (CAS: 123-11-5) also indicate that they are readily biodegradable.

 

Environmental fate

According to the fugacity model levels III, the most likely environmental fate for this test chemical is soil (i.e.estimated to 72.7%). In soil,4-methoxyphenylacetonewas expected to have moderate mobility based upon a Log KOC value ranging from 1.7732 to 2.27, respectively. The half-life in soil (75 days estimated by EPI suite) indicates that the chemical is not persistent in soil and the exposure risk to soil dwelling animals is moderate to low.

 

If released in to the environment, 26.8% of the chemical will partition into water according to the Mackay fugacity model level III in EPI suite version 4.1 (2017). However, the half-life (37.5 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.

 

Moreover, its persistent characteristic is only observed in the sediment compartment but Fugacity modelling shows that sediment is not an important environmental fate (less than 1% i.e. reported as 0.127% when estimated by EPI Suite version 4.1).

 

Hence it has been concluded that4-methoxyphenylacetoneis not persistent in nature.

 

Bioaccumulation assessment

The tested substance does not fulfil the B criterion within Annex XIII based on the assessment that here follows:

 

Theestimated BCF value from authoritative database was determined to be range from 4.922 to 10.7, respectively and theoctanol water partition coefficient of the test chemical is 1.55, which is less than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a low risk for the chemical to bioaccumulate in fish and food chains.

 

Toxicity assessment

The tested substance does not fulfil the T criterion within Annex XIII based on the assessment that here follows:

 

Mammals

The tested chemical is regarded to be not classified for carcinogenicity, mutagenicity and reprotoxicity, Further, there is no evidence of chronic toxicity, as identified by the classifications STOT (repeated exposure), category 1(oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume) or category 2 (oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume).

 

Aquatic organisms

All of the available short-term eco-toxicity estimations for fish, invertebrates and algae for the substance indicates the LC50/EC50 value to be in the range 203.376– 463.20 mg/L, respectively. These value suggest that the substance is not likely to be hazardous to Aquatic organisms at environmentally relevant concentrations and can be considered to be ‘not classified’ as per the CLP regulation.

 

By speculation, long-term NOEC for aquatic organisms were not expected for the substance4-methoxyphenylacetoneat concentration below 0.01 mg/L based on the data mentioned above

 

The chemical was therefore not considered as hazardous to aquatic environments as per the criteria set out in Annex XIII.

 

Conclusion

Based on critical, independent and collective evaluation of information summarized herein, the tested compound does not fulfil the P, B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.