Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Data for Pitch, coal tar, high-temp., < 1% 4- to 5-membered condensed ring aromatic hydrocarbons [EC no. 701-305-8] (CTPhtht) is not available. Results from a cell multiplication inhibition test with the supporting substance Pitch, coal tar, high temp. [CAS no. 65996-93-2] is used instead to characterise the toxicity of CTPhtht to microorganisms. No inhibitory effect was observed up to a nominal concentration of 10000 mg/L (loading).

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:
10 000 mg/L

Additional information

No experimental data is available for the substance Pitch, coal tar, high-temp., < 1% 4- to 5-membered condensed ring aromatic hydrocarbons [EC no. 701-305-8] (CTPhtht) itself, but data have been identified for Pitch, coal tar, high temp. [CAS no. 65996-93-2], the precursor material. This is used as supporting substance. Coal tar pitch, high termp. is closely structure-related to CTPhtht, and comprises also an inert matrix of highly ring-condensed polycyclic aromatic hydrocarbons. Due to the production process, the target substance CTPhtht will be depleted of available single PAH constituents compared to Pitch, coal tar, high temp. [CAS no. 65996-93-2]. Therefore, results originating from coal tar pitch, high temp., can be considered as worst-case situation.

Toxicity to microorganism was tested with coal tar pitch in a Pseudomonas putida cell multiplication inhibition test (Hillmann E. 1991). No inhibition was detected at a loading of 10,000 mg/L (EL0 = 10,000 mg/L).