Naphthenic acids

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

P/vP-criterion: Measured data on naphthenic acids and QSAR estimations for potential components of naphthenic acids, show that naphthenic acids are inherently to ready biodegradable. Microbial degradation is the predominant factor in the reduction of aquatic acute toxicity of naphthenic acids. Naphthenic acids are not P (and not vP).

B-criterion: A BCF of 2 L/kg wet-wt based, was measured in Rainbow trout for one C-13 component of naphthenic acids, by Young et al. (2008). The Japanese METI-NITI database reports a range of BCF between 1.6 and 27 L/kg wet-wt for sodium naphthenate. The BCF value is below the Annex XIII limit of 2000 L/kg. Naphthenic acids are not B (and not vB).

T-criterion: Naphthenic acids are not classified as carcinogenic (category 1A or 1B), as germ cell mutagenic (category 1A or 1B), as toxic for reproduction (category 1A or 1B) or for specific target organ toxicity after repeated exposure (STOT RE category 1A or 1B), according CLP Regulation EC No 1272/2008. The chronic NOEC for aquatic organisms is expected to be above the cut-off value of 0.01 mg/l (based on available information).

Anthracene is a PBT substance occurring in petroleum substances. Analysis of one sample that is representative for this dossier, showed a concentration of 0.0014% w/w for anthracene (See IUCLID section 1.4). This concentration is below the limit value for PBT components of 0.1%. Naphthenic acids can not be regarded as PBT substance due to their anthracene content.