2,4,6-trimethylphenol

PBT assessment

PBT assessment: overall result

Reference

Reference 1

Name:

Mesitol high purity grade_boundary composition

Type of composition:

boundary composition of the substance

State / form:

other: solid: crystalline

Reference substance:

Mesitol high purity grade_boundary composition

Reference 2

Name:

Mesitol technical grade_boundary composition

Type of composition:

boundary composition of the substance

State / form:

other: solid: crystalline

> 80 - < 100 % (w/w)

Reference substance:

Mesitol technical grade_boundary composition

Reference substance:

Mesitol technical grade_boundary composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_boundary composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_boundary composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_boundary composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_boundary composition

This impurity is considered relevant for the classification and labelling of the substance

Reference 3

Name:

Mesitol technical grade_legal entity composition

Type of composition:

legal entity composition of the substance

State / form:

other: solid: crystalline

> 80 - < 95 % (w/w)

Reference substance:

Mesitol technical grade_legal entity composition

Reference substance:

Mesitol technical grade_legal entity composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_legal entity composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_legal entity composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_legal entity composition

This impurity is considered relevant for the classification and labelling of the substance

Reference substance:

Mesitol technical grade_legal entity composition

This impurity is considered relevant for the classification and labelling of the substance

PBT status:

the substance is not PBT / vPvB

Justification:

The PBT Assessment is based on the criteria set out in the “Guidance on information requirements and chemical safety assessment, Chapter R.11: PBT Assessment” (ECHA, 2017).

Persistence (P) Assessment

2,4,6-trimethylphenol (CAS 527-60-6) is not readily biodegradable in a study according to the OECD 301D (11.3% in 28 days).

 

One biodegradation simulation study is available for 2,4,6-trimethylphenol investigating the degradation of the substance in surface water (OECD 309). The study was performed with two concentration levels, a high nominal test item concentration of 100 µg/L and a low concentration level of 10 µg/L respectively. The test duration was 60 days. The derived DT50 values for primary degradation to unknown degradation products were 2.7 days for 10 µg/L at 20°C (recalculation to 12°C: DT50 = 5.7 days) and 10.8 d for 100 µg/L at 20°C (recalculation to 12°C: 22.9 days). The overall mineralization rate to CO2 reached a maximum of 9% AR (high dose) and 11.6% AR (low dose) after 60 days. Thus, based on the mineralisation rate, the criteria for vP are fulfilled and the substance is considered to be very persistent (vP) according to Guidance on Information Requirements and Chemical Safety Assessment, Chapter R.11: PBT/vPvB assessment (ECHA; 2017) as the DT50 for mineralisation is > than 60 days. 

 

Bioaccumulation (B) assessment

2,4,6-trimethylphenol has a log Kow of 2.73 (HPLC Method), which is below the trigger value of 3. This is also supported by a study published in 1982 by the Japanese Government. Respective results showed for a six-week lasting experiment with Cyprinus carpio under flow-through conditions and considering exposure concentrations of 0.2 and 0.02 ppm, BCF values as high as ≥ 6.5 to ≤ 10 L/Kg and ≥ 2.7 to ≤ 8.1 L/Kg, respectively. These data support the very low bioaccumulation potential of 2,4,6-trimethylphenol, as the bioconcentration factor in aquatic species is lower than 2000 based on the Guidance on Information Requirements and Chemical Safety Assessment, Chapter R.11: PBT/vPvB assessment (ECHA, 2017). Thus, the substance does not meet the screening criterion for bioaccumulation and is not considered to be bioaccumulative (B) or very bioaccumulative (vB).

 

Toxicity (T) assessment

For 2,4,6-trimethylphenol the available acute effect concentrations are > 0.1 mg/L (fish, aquatic invertebrates, algae) and the chronic effect concentration (fish, aquatic invertebrates, algae) is ≥ 0.01 mg/L.

Furthermore, the substance is not classified as carcinogenic (category 1A or 1B), germ cell mutagenic (category 1A or 1B) or toxic for reproduction (category 1A, 1B or 2) according to the consolidated version of Regulation (EC) No. 1272/2008 and all further amendments (ATPs). Additionally, the substance shows no specific target organ toxicity after repeated exposure (STOT RE category 1 or 2) according to the consolidated version of Regulation (EC) No. 1272/2008 and all further amendments (ATPs). 

Thus, 2,4,6-trimethylphenol is not considered to meet the T criterion.

 

 

Summary and overall conclusions on PBT or vPvB properties

 

Overall conclusion: The substance is not PBT/vPvB.