Geranyl phenylacetate

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Classification of Geranyl phenylacetate for effects in the environment:

 

The chemical Geranyl phenylacetate (CAS no. 102-22-7) is used as a flavour and fragrance agent. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Geranyl phenylacetate. 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 fulfils the P criterion within Annex XIII based on the assessment that here follows:

 

Biotic degradation

Biodegradability of test chemical (2E)-3,7-dimethylocta-2,6-dien-1-yl 2-phenylacetate (CAS no.102-22-7) is predicted using OECD QSAR tool box v.3.3 using log Kow as primary descriptor. The test chemical (2E)-3,7-dimethylocta-2,6-dien-1-yl 2-phenylacetate undergoes 16 % biodegradation by taking BOD as parameter and microorganisms as inoculums in 28 days. Therefore it is concluded that test chemical (2E)-3,7-dimethylocta-2,6-dien-1-yl 2-phenylacetate is not readily biodegradable.

 

Another prediction done by using Estimation Programs Interface Suite (EPI suite, 2017) to estimate the biodegradation potential of the test compound (2E)-3,7-dimethylocta-2,6-dien-1-yl 2-phenylacetate (CAS no.102-22-7) in the presence of mixed populations of environmental microorganisms. The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical (2E)-3,7-dimethylocta-2,6-dien-1-yl 2-phenylacetate is expected to be not readily biodegradable.

 

Experimental results from the similar substances (CAS: 10453-86-8 and 103-50-4) also indicate that they are not 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 78.3%). In soil, 1,1'-(4-chlorobutylidene)bis[4-fluorobenzene] was expected to have negligible to slow mobility based upon a LogKOC in the range 3.41 – 4.59. Thehalf-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, 10.5 % and 11.1 of the chemical will partition into water and sediment respectively, according to the Mackay fugacity model level III in EPI suite version 4.1 (2017). The half-life (37.5 days in water and 337.5 days in sediment as estimated by EPI suite) chemical is not persistent in water but persistent in sediment.

 

Although the half-life value in sediment indicate the chemical to be Very persistent (vP), since only predicted data is available for the substance, it has been concluded that Geranyl phenylacetate is persistent in nature.

 

 

Bioaccumulation assessment

The tested substance fulfils the B criterion within Annex XIII based on the assessment that here follows:

 

Theestimated BCF value from authoritative database was determined to be in the range 5581 - 18423 and theoctanol water partition coefficient of the test chemical is 6.18 which is more than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a high risk for the chemical to bioaccumulate in fish and food chains.

 

Although the BCF value indicate the chemical to be Very bioaccumulative (vB), since only predicted data is available for the substance, it has been concluded that Geranyl phenylacetate is bioaccumulative inin 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

 

As per Column 2 (Annex VIII) of the REACH regulation, a study does not need to be conducted if there are mitigating factors indicating that aquatic toxicity is unlikely to occur for instance if the substance is highly insoluble in water. The test substance was determined to be highly insoluble in water (solubility= 0.09 mg/L). 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 fulfils the P and B criterion but does not fulfil the T criterion and has therefore not been classified as a PBT compound within Annex XIII.