3,4-xylenol

Bioaccumulation: aquatic / sediment

Administrative data

Endpoint:

bioaccumulation: aquatic / sediment

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Materials and methods

Test guideline

Guideline:

other: Calculation with EPISUITE 4.11

Test material

Test material information

Constituent 1

Reference substance name:

3,4-xylenol

EC Number:

202-439-5

EC Name:

3,4-xylenol

Cas Number:

95-65-8

Molecular formula:

C8H10O

IUPAC Name:

3,4-dimethylphenol

Results and discussion

Bioaccumulation factor

Bioaccumulation factor 1

Type:

BCF

Value:

13.8 L/kg

Basis:

whole body w.w.

Calculation basis:

other: Log Kow

Remarks on result:

other: estimated

Bioaccumulation factor 2

Type:

BAF

Value:

10.9 L/kg

Basis:

whole body w.w.

Calculation basis:

other: log Kow

Remarks on result:

other: estimated

Any other information on results incl. tables

SMILES : Oc(ccc(c1C)C)c1

CHEM : Phenol, 3,4-dimethyl-

MOL FOR: C8 H10 O1

MOL WT : 122.17

--------------------------------- BCFBAF v3.01 --------------------------------

Summary Results:

Log BCF (regression-based estimate): 1.14 (BCF = 13.8 L/kg wet-wt)

Biotransformation Half-Life (days) : 0.0823 (normalized to 10 g fish)

Log BAF (Arnot-Gobas upper trophic): 1.04 (BAF = 10.9 L/kg wet-wt)

=============================

BCF (Bioconcentration Factor):

=============================

Log Kow (estimated) : 2.61

Log Kow (experimental): 2.23

Log Kow used by BCF estimates: 2.23

Equation Used to Make BCF estimate:

Log BCF = 0.6598 log Kow - 0.333 + Correction

Correction(s): Value

No Applicable Correction Factors

Estimated Log BCF = 1.138 (BCF = 13.75 L/kg wet-wt)

===========================================================

Whole Body Primary Biotransformation Rate Estimate for Fish:

===========================================================

------+-----+--------------------------------------------+---------+---------

TYPE | NUM | LOG BIOTRANSFORMATION FRAGMENT DESCRIPTION | COEFF | VALUE

------+-----+--------------------------------------------+---------+---------

Frag | 1 | Aromatic alcohol [-OH] | -0.4727 | -0.4727

Frag | 2 | Alkyl substituent on aromatic ring | 0.1781 | 0.3561

Frag | 2 | Aromatic-CH3 | -0.0872 | -0.1743

Frag | 3 | Aromatic-H | 0.2664 | 0.7991

Frag | 1 | Benzene | -0.4277 | -0.4277

L Kow| * | Log Kow = 2.23 (experimental ) | 0.3073 | 0.6854

MolWt| * | Molecular Weight Parameter | | -0.3133

Const| * | Equation Constant | | -1.5371

============+============================================+=========+=========

RESULT | LOG Bio Half-Life (days) | | -1.0845

RESULT | Bio Half-Life (days) | | 0.08232

NOTE | Bio Half-Life Normalized to 10 g fish at 15 deg C |

============+============================================+=========+=========

Biotransformation Rate Constant:

kM (Rate Constant): 8.42 /day (10 gram fish)

kM (Rate Constant): 4.735 /day (100 gram fish)

kM (Rate Constant): 2.663 /day (1 kg fish)

kM (Rate Constant): 1.497 /day (10 kg fish)

Arnot-Gobas BCF & BAF Methods (including biotransformation rate estimates):

Estimated Log BCF (upper trophic) = 1.036 (BCF = 10.88 L/kg wet-wt)

Estimated Log BAF (upper trophic) = 1.036 (BAF = 10.88 L/kg wet-wt)

Estimated Log BCF (mid trophic) = 0.971 (BCF = 9.348 L/kg wet-wt)

Estimated Log BAF (mid trophic) = 0.971 (BAF = 9.348 L/kg wet-wt)

Estimated Log BCF (lower trophic) = 0.941 (BCF = 8.736 L/kg wet-wt)

Estimated Log BAF (lower trophic) = 0.941 (BAF = 8.738 L/kg wet-wt)

Arnot-Gobas BCF & BAF Methods (assuming a biotransformation rate of zero):

Estimated Log BCF (upper trophic) = 1.280 (BCF = 19.05 L/kg wet-wt)

Estimated Log BAF (upper trophic) = 1.294 (BAF = 19.67 L/kg wet-wt)

Applicant's summary and conclusion

Conclusions:

The bioaccumulation potential of 3,4-Dimethylphenol is expected to be low, because the log Kow is 2.23 and the calculated BCF-/BAF-Values are 13.8 / 10.9 L/kg wet-wt. The actual ECHA Guidance as well as the most recent ECETOC-Report state, that a Log Kow < 4.5 is a definitive indicator for non B/vB properties in aquatic systems. According to the ECHA Guidance the uptake of an organic substance is driven by its hydrophobicity. For organic substances with a log Kow value below 4.5 it is assumed that the affinity for the lipids of an organism is insufficient to exceed the B criterion, i.e. a BCF value of 2000 L/kg.