1. Interpretation of Descriptor 8
“Concentrations of contaminants are at levels not giving rise to pollution effects”
What is included
All contaminants
What is not included
Biotoxins (natural products)
Oil slicks (PAH are included whether from oil or combustion sources)
Nutrients (Descriptor 5)
Energy (Descriptor 11)
Fish and shellfish for human consumption (Descriptor 9)

2. Attributes
Concentrations of contaminants in water, sediment and biota are below assessment thresholds identified on the basis of toxicological data
Levels of pollution effects are below assessment thresholds representing harm at organism, population, community and ecosystem levels
Concentrations of contaminants in water, sediment and biota, and the occurrence and severity of pollution effects, should not be increasing

3. CRITERIA used for the evaluation of the attribute
Contaminant concentrations are below toxicologically based assessment criteria (e.g. Environmental Quality Standards, Environmental Assessment Criteria)
Levels of pollution effects determined using biological effects methods are below defined thresholds of harm (e.g. as developed by ICES/OSPAR)
Neither contaminant concentrations nor pollution effect levels are increasing over time (no deterioration)

4. Indicators
Concentrations of contaminants and their trends in water, sediment and biota
Levels of pollution effects and their trends measured using appropriate methodologies, e.g. biological responses measurement, bioassays, etc
In both cases these need further elaboration, and could vary regionally depending on local concerns and varying activities leading to differences in contaminant inputs