Assessment criteria for biological effects

Two assessment criteria are used to assess biological effects: the

The assessment criteria were developed within the Oslo and Paris Commission framework with scientific advice from the International Council for the Exploration of the Sea. The comparison of mean values with the assessment criteria depends on whether a low or a high value of the biological effect indicates a healthy organism. If a low (high) value indicate health, then mean values significantly below (above) the BAC are said to be near background and values below (above) the EAC indicate no chronic effects on the organisms concerned. Full details can be found in Davies & Vethaak (2012) and OSPAR (2013).

Davies, I. M. and Vethaak, A. D. 2012. Integrated marine environmental monitoring of chemicals and their effects. ICES Cooperative Research Report No. 315. 277 pp.

OSPAR, 2013. Background documents and technical annexes for biological effects monitoring (Update 2013). OSPAR Commission, London. Publication 589, 238 pp.

BACs and EACs are available for the following biological effects:


species common name sex matrix BAC
Gadus morhua cod both liver microsome 145.0
Limanda limanda dab female liver S9 178.0
male liver S9 147.0
both liver microsome 680.0
Callionymus lyra dragonet both liver microsome 202.0
Platichthys flesus flounder male liver S9 24.0
Lepidorhombus boscii four spotted megrim both liver microsome 13.0
Pleuronectes platessa plaice male liver S9 9.5
both liver microsome 255.0
Mullus barbatus red mullet male liver S9 208.0


  • units are pmol min\(^{-1}\) mg S9 protein\(^{-1}\) or pmol min\(^{-1}\) mg microsomal protein\(^{-1}\) for the liver S9 and liver microsome matrices respectively
  • there are no EACs
  • low values indicate healthy organisms

Bile metabolites

bile metabolite species common name method BAC EAC
1-OH pyrene Gadus morhua cod HPLC-F 21.00
GC-MS 483
Limanda limanda dab HPLC-F 16.00
Platichthys flesus flounder HPLC-F 16.00
Melanogrammus aeglefinus haddock HPLC-F 13.00
1-OH pyrene equivalents Gadus morhua cod SSF 1.10 35
Limanda limanda dab SSF 0.15 22
Platichthys flesus flounder SSF 1.30 29
Melanogrammus aeglefinus haddock SSF 1.90 35
1-OH phenanthrene Gadus morhua cod HPLC-F 2.70
GC-MS 528
Limanda limanda dab HPLC-F 3.70
Platichthys flesus flounder HPLC-F 3.70
Melanogrammus aeglefinus haddock HPLC-F 0.80


  • HPLC-F is high performance liquid chromatography - fluorescence, GC-MS is gas chromatography - mass spectrometry, and SSF is synchronous scan fluorescence 341/383 nm
  • units are ng ml\(^{-1}\) for HPLC-F, ng g\(^{-1}\) for GC-MS, and pyrene-type \(\mu\)g ml\(^{-1}\) for SSF
  • the proliferation of methods and units are a mystery to all those who have not devoted their lives to the study of bile metabolites
  • low values indicate healthy organisms

Scope for growth

species BAC EAC
mussels 25 15


  • units are J h\(^{-1}\) g\(^{-1}\)
  • high values indicate healthy mussels

Stress on stress

species BAC EAC
mussels 10 5


  • units are days
  • high values indicate healthy mussels

Comet assay

species common name BAC
Mytilus edulis blue mussel 10
Gadus morhua cod 5
Limanda limanda dab 5


  • units are %
  • there are no EACs
  • low values indicate healthy organisms

Micronucleus assay

species common name matrix BAC
Mytilus edulis blue mussel gill 2.5
blood 2.5
Mytilus galloprovincialis Mediteranean mussel blood 3.9
Mytilus trossulus bay mussel blood 4.5
Platichthys flesus flounder blood 0.3
Limanda limanda dab blood 0.5
Zoarces viviparus eelpout blood 0.4
Gadus morhua cod blood 0.4
Mullus barbatus red mullet blood 0.3


  • units are ‰
  • there are no EACs
  • low values indicate healthy organisms

Neutral red retention time

120 50


  • units are minutes
  • high values indicate healthy organisms

Lysosomal labilisation period

20 10


  • units are minutes
  • high values indicate healthy organisms


measure species common name BAC EAC
VDS Nucella lapillus dog whelk 0.3 2.0
VDS Neptunea antiqua red whelk 0.3 2.0
VDS Nassarius reticulatus netted dog whelk 0.3
IMPS Buccinum undatum common whelk 0.3


  • low values indicate healthy organisms