PNEC
As PNEC ( p redicted n o e ffect c oncentration) refers to the predicted concentration of a dangerous for the environment, as a rule the substance to which had no impact on the environment show. If this concentration is not reached, there should be no negative effects.
PNECs are mainly used together with PECs in the risk quotient in environmental risk assessment.
calculation
Safety factor
In order to be able to use data from the laboratory, individual species and short-term studies, and to assess the effects on ecosystems, safety factors are used to take into account the uncertainty resulting from extrapolation . Depending on the data situation, safety factors of up to 1000 are used.
acute toxicity
Acute toxicity parameters include, in particular, the LC 50 and EC 50 . Ideally, data should be available for different trophic levels or taxonomic groups. The lowest available LC 50 or EC 50 is divided by the safety factor to get the PNEC.
Chronic toxicity
The PNEC for chronic toxicity is calculated based on the No Observed Effect Level or Concentration ( NOEC ). Again the most sensitive species is used. Depending on the data situation (diversity of the organisms tested), the safety factor ranges from 10 to 100, with the lowest safety factor being used if the data is good.
Web links
- Guidance on the Biocidal Products Regulation of the European Chemicals Agency - EU guidance regarding the calculation of PNECs, see Volume IV, PART B from page 127
- REACH Helpdesk - What is a PNEC?
Individual evidence
- ↑ a b c d European Chemicals Bureau : Technical Guidance Document on Risk Assessment . European Communities, 2003.
- ↑ a b c Van Sprang, P: Data compilation, selection and derivation of PNEC values for the aquatic compartment - Zinc example . OECD . 2011.
- ^ A b c The Edinburgh Center for Toxicology. Environmental Risk Assessment. UNEP / IPCS Training Module No. 3. Section B. UNEP / IPCS Training Module No. 3 Section B - Environmental Risk Assessment ( Memento of April 17, 2012 in the Internet Archive ).