Pitch, coal tar, high-temp., < 1% 4- to 5-membered condensed ring aromatic hydrocarbons

PBT assessment

PBT assessment: overall result

PBT status:

PBT assessment does not apply

Justification:

• Persistence

As indicated in the REACH Guidance of PBT assessment, Section C.1.3, page 5 [information_requirements_part_c_en.pdf, dec. 2011], persistency testing is practically not possible due to the refractory inherent properties and complexity of this UVCB substance.

Wording in the REACH Guidance:

"....However, for substances for which persistency testing is difficult or practically impossible, like e.g. for certain multi-constituent or very poorly water soluble substances, it may sometimes be more reasonable to start the PBT/vPvB assessment by evaluating the B criterion (see Section R.11.1.3.2 for further guidance)."

• Bioaccumulation

Pitch, coal tar, high-temp., < 1% 4- to 5-membered condensed ring aromatic hydrocarbons [EC no. 701-305-8] (CTPhtht) is a practically water-insoluble UVCB substance and cannot pass biological membranes due to its complex high-molecular matrix structure. Hence, a carbo pitch-specific BCF-value cannot be determined. Besides its poor bioavailability, the determination of the partition coefficient proved to be technically not feasible due to its very limited solubility (see phys.-chem. data, Chapter 1.3.). Hence, the bioaccumulation criteria for PBT are not applicable to CTPhtht itself.

Wording in the REACH Guidance, Section C.1.4.2, page 6:

"...However, for a substance produced or imported at a level of 100 t/y or more, information on bioconcentration in aquatic species has to be made available by the registrant and to be considered in the assessment, unless this information can be waived according to column 2 of Annex IX or according to Annex XI(3) (e.g. low bioaccumulation potential, no exposure, testing technically not possible)."

• Toxicity Assessment

Based on structure-analogy, Pitch, coal tar, high-temp., < 1% 4- to 5-membered condensed ring aromatic hydrocarbons [EC no. 701-305-8] (CTPhtht), is not expected to show chronic aquatic toxicity under standard experimental conditions. However, it has been self-classified as CMR substance, based on BaP content. The current re-evaluation concludes: Carc. 1B, Muta. 1B, and Repr. 1B. Therefore, the T criterion is fulfilled.