Choline hydrogen carbonate

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

Criteria for assessing PBT properties are defined in Annex XIII, REACH Regulation (EC) No. 1907/2006. Further details are laid down in ECHA Guidance on Information Requirements and Chemical Safety Assessment; Chapter R.11: PBT Assessment (May 2008). The assessment of PBT / vPvB properties is based upon a separate assessment for each parameter (i.e. P or vP, B or vB and T). Substances are only assigned as PBT or vPvB when they fulfill the criteria for all three properties (persistency, bioaccumulation and toxicity in case of PBT substance) or both criteria (i.e. very persistent and very bioaccumulative) in case of vPvB, respectively.

Experimental results from the read-across substance Choline chloride (CAS 67-48-1) are taken into account in order to complete the PBT/vPvB assessment for the target substance Choline hydrogen carbonate. This procedure is reliable; for justification, please refer to the Read-Across Statement of Chemservice S.A. (2013). Thus the same conclusions regarding PBT properties are drawn for the registered substance. In the following, the read across procedure is not mentioned separately, however, the assessment applies to the target as well as to the read-across substance. Based on a valid experimental result, Choline chloride is considered as "readily biodegradable" (BASF AG, 1988) and therefore not persistent in the environment. Also the B criterion (Bioaccumulative substance) is not fulfilled based on the experimentally determined logPow of -3.77 of the read-across substance (BASF AG, 1988). The QSAR predicted Bioconcentration Factor (BCF) is determined as 3.16 L/kg for both, Choline chloride as well as for Choline hydrogen carbonate (Chemservice S.A., 2013). This is which is far below the trigger value of 100 L/kg. Due to the lack of toxicity observed in all available ecotoxicity studies, also the first T screening criterion is not fulfilled. Furthermore, no classification exists as carcinogenic, mutagenic or toxic for reproduction according to Regulation (EC) No. 1272/2008. The test substance is neither classified as "T, R48" or as "Xn, R48" based on the criteria laid down in Directive 67/548/EEC nor as STOT RE category 1 or 2 so far.

As conclusion, Choline hydrogen carbonate fulfills none of the required parameters and is neither a PBT nor a vPvB substance.

Likely routes of exposure:

Choline hydrogen carbonate is a aqueous, colorless and odourless liquid. Workers may be exposed via the dermal route due to substance handling during manufacture. Based on the substance specific properties (i.e. negative logPow and molecular weight range) the substance will be able to diffuse into the dermis but no deeper layers of the skin, i.e. neither the epidermis nor any bloodstream layers will be crossed. Based on the low vapour pressure of the substance, an uptake via the inhalative route is not relevant. Oral exposure is not relevant based on the handling, education and safety precautions in the factory. As conclusion, only the dermal exposure route may be relevant for humans.