Registration Dossier

Ecotoxicological information

Endpoint summary

Currently viewing:

Administrative data

Description of key information

Additional information

Benzo(a)pyrene is selected as key marker substance in pitch for deriving a PNEC(soil):

The toxicity values found in literature show high variation from almost 1000 mg/kg soil down to less than 10 mg/kg soil dw. In the risk assessment report on coal-tar pitch [EU 2008], the estimate of 2.6 mg/kg soil dw for a NOEC/EC10 of reproduction in earthworm based on results of Achazi et al. (1995) is considered as relevant for deriving a PNEC.

The following summary is from EU 2008, 3.2.2.14:

"Chronic toxicity studies with benzo(a)pyrene are available for 2 species each of terrestrial annelids, crustaceans, and collembola. No effects were found for the studies with Folsomia species (Sverdrup et al., 2002e; Bleeker et al., 2003; Droge et al., 2006). For annelids, effects were observed in one study only, with Eisenia fetida being slightly more sensitive than Enchytraeus crypticus (Achazi et al., 1995). The NOECs for reproduction are 2.6 and 8.7 mg/kg dwt respectively, recalculated to a soil with 2% organic carbon. For the crustaceans Oniscus asellus and Porcellio scaber effects were observed in tests that were conducted in contaminated food with an organic matter content of more than 90% (Van Straalen & Verweij, 1991; Van Brummelen & Stuijfzand, 1992; Van Brummelen et al., 1996). ........ The EC10 for growth efficiency of male isopods of 0.53 mg/kg dwt is comparable with the concentrations at which 10% effect or more was observed in the study by Van Brummelen & Stuijfzand (1992) ......" [EU 2008: RAR Coal-Tar Pitch].

Conclusion by the registrant: The latter value generated on food with the crustaceans is considered to be not comparable to soil conditions and hence not representative (comp. also benz(a)anthracene). The lowest NOEC for reproduction of 2.6 mg/kg dw (Achazi et al. 1995) is considered relevant, but has to be divided by an AF of 50. Therefore, the same PNEC of 0.05 results.